Vaxart, Inc. (Form: S-1/A, Received: 04/08/2019 09:34:13)

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As filed with the U.S. Securities and Exchange Commission on April 8, 2019

Registration No. 333-229536

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

Amendment No. 2
to
FORM S-1

REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

VAXART, INC.
(Exact name of registrant as specified in its charter)


Delaware (State or other jurisdiction of incorporation or organization)		2834 (Primary Standard Industrial Classification Code Number)		59-1212264 (I.R.S. Employer Identification No.)

290 Utah Ave
Suite 200
South San Francisco, California 94080
(650) 550-3500
(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)

Wouter W. Latour M.D.
President and Chief Executive Officer
290 Utah Ave
Suite 200
South San Francisco, California 94080
(650) 550-3500
(Name, address, including zip code, and telephone number, including area code, of agent for service)


Copies to:
John T. McKenna Josh Seidenfeld Cooley LLP 3175 Hanover Street Palo Alto, California 94304 (650) 843-5000		Gary Emmanuel Heidi Steele McDermott Will & Emery LLP 340 Madison Avenue New York, New York 10173 (212) 547-5400

Approximate date of commencement of proposed sale to public: As soon as practicable after the effective date of this registration statement.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, as amended, check the following box: ý

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective Registration Statement for the same offering: o

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, please check the following box and list the Securities Act Registration Statement number of the earlier effective Registration Statement for the same offering: o

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act Registration Statement number of the earlier effective Registration Statement for the same offering: o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act.


Large Accelerated Filer o		Accelerated Filer o		Non-accelerated Filer ý		Smaller Reporting Company ý Emerging growth company o

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act of 1933, as amended. o

CALCULATION OF REGISTRATION FEE

Title of Each Class of Securities to be Registered	Proposed Maximum Aggregate Offering Price(1)	Amount of Registration Fee(1)




Common Stock, par value $0.10 per share	$11,580,500(2)

Pre-funded warrants to purchase shares of common stock and common stock issuable upon exercise thereof	$10,070,000(3)

Common warrants to purchase shares of common stock and common stock issuable upon exercise thereof	$11,580,500(2)

Representative warrants to purchase shares of common stock and common stock issuable upon exercise thereof	$1,013,294(4)

Total	$34,244,294(5)	$4,151

(1): Estimated solely for purposes of computing the amount of the registration fee pursuant to Rule 457(o) under the Securities Act. The registrant paid $3,335 with the filing of this registration statement.
(2): Includes securities that the underwriters have the option to purchase.
(3): The proposed maximum aggregate offering price of the common stock proposed to be sold in the offering will be reduced on a dollar-for-dollar basis based on the aggregate offering price of the pre-funded warrants offered and sold in the offering (plus the aggregate exercise price of the common stock issuable upon exercise of the pre-funded warrants), and as such the proposed aggregate maximum offering price of the common stock and pre-funded warrants (including the common stock issuable upon exercise of the pre-funded warrants), if any, is $11,580,500.
(4): Represents warrants issuable to H.C. Wainwright & Co., LLC (the "representative warrants") to purchase a number of shares of common stock equal to 7% of the number of shares of common stock and pre-funded warrants being offered at an exercise price equal to 125% of the public offering price. Resales of the representative warrants on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, as amended, are registered hereby. See "Underwriting."
(5): Pursuant to Rule 416, the securities being registered hereunder include such indeterminate number of additional securities as may be issuable to prevent dilution resulting from stock splits, dividends or similar transactions.

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment that specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the Registration Statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

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The information in this preliminary prospectus is not complete and may be changed. We may not sell these securities or accept an offer to buy these securities until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell these securities and it is not soliciting offers to buy these securities in any state where such offer or sale is not permitted.

PRELIMINARY PROSPECTUS SUBJECT TO COMPLETION, DATED APRIL 8, 2019

5,300,000 Shares of Common Stock

Pre-Funded Warrants to Purchase Shares of Common Stock

Common Warrants to Purchase 5,300,000 Shares of Common Stock

We are offering up to 5,300,000 shares of our common stock and common warrants to purchase an aggregate of 5,300,000 shares of our common stock (and the shares of common stock that are issuable from time to time upon exercise of the common warrants). We are also offering to certain purchasers whose purchase of shares of common stock in this offering would otherwise result in the purchaser, together with its affiliates and certain related parties, beneficially owning more than 4.99% (or, at the election of the purchaser, 9.99%) of our outstanding common stock immediately following the consummation of this offering, the opportunity to purchase, if any such purchaser so chooses, pre-funded warrants, in lieu of shares of common stock that would otherwise result in such purchaser's beneficial ownership exceeding 4.99% (or, at the election of the purchaser, 9.99%) of our outstanding common stock. Each pre-funded warrant will be exercisable for one share of our common stock and will be accompanied by a common warrant to purchase one share of common stock. The purchase price of each pre-funded warrant will be equal to the price at which a share of common stock is sold to the public in this offering, minus $0.10, and the exercise price of each pre-funded warrant will be $0.10 per share. The pre-funded warrants will be immediately exercisable and may be exercised at any time until all of the pre-funded warrants are exercised in full. This offering also relates to the shares of common stock issuable upon exercise of the common warrants and any pre-funded warrants sold in this offering. For each pre-funded warrant we sell, the number of shares of common stock we are offering will be decreased on a one-for-one basis. Therefore the number of common warrants sold in this offering will not change as a result of a change in the mix of the shares of our common stock and pre-funded warrants sold. The common warrants will be exercisable immediately and will expire five years from the date of issuance. The shares of common stock and pre-funded warrants, and the accompanying common warrants, can only be purchased together in this offering but will be issued separately and will be immediately separable upon issuance. Our common stock is listed on the Nasdaq Capital Market under the symbol "VXRT." On April 5, 2019, the last reported sale price of our common stock was $1.90 per share. The actual public offering price per share of common stock and any pre-funded warrant will be determined between us and the underwriters at the time of pricing, and may be at a discount to the current market price. Therefore, the assumed public offering price used throughout this prospectus may not be indicative of the final offering price. There is no established public trading market for the pre-funded warrants and the common warrants, and we do not expect a market to develop. In addition, we do not intend to apply for a listing of the pre-funded warrants and the common warrants on any national securities exchange or other nationally recognized trading system.

Investing in our securities involves a high degree of risk. You should carefully read and consider the "Risk Factors" beginning on page 11 of this prospectus before investing.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

	Per Share	Per Pre-Funded Warrant	Per Common Warrant	Total(2)

Public offering price	$	$	$	$
Underwriting discounts and commissions(1)	$	$	$	$
Proceeds, before expenses, to us	$	$	$	$

(1): In addition, we have agreed to issue to H.C. Wainwright & Co., LLC or its designees warrants to purchase a number of shares of common stock equal to 7.0% of the shares of common stock and pre-funded warrants sold in this offering. See "Underwriting" for additional information and a description of the compensation payable to the underwriters.
(2): The public offering price is $ per share of common stock, $ per pre-funded warrant and $ per accompanying common warrant.

We have granted the underwriters the right to purchase up to 795,000 additional shares of our common stock and/or common warrants to purchase up to an aggregate of an additional 795,000 shares of common stock, in each case at the public offering price, less underwriting discounts and commissions. The underwriters can exercise this right at any time within 30 days from the date of this prospectus. If the underwriters exercise their option to purchase additional shares and/or common warrants in full, the total underwriting discounts and commissions payable by us will be $ and the total proceeds to us from this offering, before expenses, will be $ , excluding the proceeds, if any, from the exercise of the pre-funded warrants or common warrants.

We anticipate that delivery of the common stock, any pre-funded warrants and accompanying common warrants will be made on or about , 2019.

Sole Book-Running Manager

H.C. Wainwright & Co.

Manager

CIM Securities, LLC

The date of this prospectus is , 2019.

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		Page

Prospectus Summary			1
The Offering			7
Risk Factors			11
Special Note Regarding Forward-Looking Statements			13
Market and Industry Data			15
Use of Proceeds			16
Dividend Policy			17
Capitalization			18
Dilution			20
Principal Stockholders			22
Description of Capital Stock			24
Description of Securities We Are Offering			27
Underwriting			30
Material U.S. Federal Income Tax Consequences			34
Legal Matters			41
Experts			41
Where You Can Find More Information			42
Incorporation of Certain Information by Reference			43

We and the underwriters have not authorized anyone to provide any information or to make any representations other than those contained in or incorporated by reference in this prospectus or in any free writing prospectuses prepared by or on behalf of us or to which we have referred you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. This prospectus is an offer to sell only the shares offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so. The information contained in or incorporated by reference in this prospectus is accurate only as of its date regardless of the time of delivery of this prospectus or of any sale of common stock or pre-funded warrants and accompanying common warrants.

Neither we nor the underwriters have done anything that would permit this offering or possession or distribution of this prospectus in any jurisdiction where action for that purpose is required, other than in the United States. Persons who come into possession of this prospectus and any free writing prospectus in jurisdictions outside the United States are required to inform themselves about and to observe any restrictions as to this offering and the distribution of this prospectus and any free writing prospectus applicable to that jurisdiction.

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PROSPECTUS SUMMARY

This summary highlights certain information about us, this offering and selected information contained elsewhere in this prospectus and in the documents incorporated by reference. This summary is not complete and does not contain all of the information that you should consider before deciding whether to invest in our securities. For a more complete understanding of our company and this offering, we encourage you to read and consider carefully the more detailed information contained in or incorporated by reference in this prospectus, including the information contained under the heading "Risk Factors" beginning on page 9 of this prospectus, and the information included in any free writing prospectus that we have authorized for use in connection with this offering.

Throughout this prospectus, the terms "we," "us," "our," and "our company" refer to Vaxart, Inc.

Overview

We are a clinical-stage biotechnology company focused on the development of oral recombinant vaccines based on our proprietary oral vaccine platform. Our oral vaccines are designed to generate broad and durable immune responses that protect against a wide range of infectious diseases and may be useful for the treatment of chronic viral infections and cancer. Our vaccines are administered using a convenient room temperature-stable tablet, rather than by injection.

We are developing prophylactic vaccine candidates that target a range of infectious diseases. These include norovirus, a widespread cause of acute gastro-intestinal enteritis, for which two Phase 1 human studies have been completed; seasonal influenza, for which our vaccine protected patients in a recent Phase 2 challenge study; and respiratory syncytial virus, or RSV, a common cause of respiratory tract infections. In addition, we are developing our first therapeutic immune-oncology vaccine targeting cervical cancer and dysplasia caused by human papillomavirus, or HPV.

Vaccines have been essential in eradicating or significantly reducing multiple devastating infectious diseases, including polio, smallpox, mumps, measles, diphtheria, hepatitis B, influenza, human papillomavirus and several others. According a recent MarketsandMarkets research report "Vaccines Market—Global Forecast to 2023", the global market for vaccines is expected to reach $50.42 billion by 2023 from $36.45 billion in 2018, at a compound annual growth rate of 6.7%.

We believe our oral tablet vaccine candidates offer several important advantages:

•: First, they are designed to generate broad and durable immune responses, including systemic, mucosal and T cell responses, which may enhance protection against certain infectious diseases, such as influenza, norovirus and RSV, and may have potential clinical benefit for certain cancers and chronic viral infections, such as those caused by HPV.
•: Second, our tablet vaccine candidates are designed to provide a more efficient and convenient method of administration, enhance patient acceptance and reduce distribution bottlenecks, which we believe will improve the effectiveness of vaccination campaigns. For example, according to the U.S. Centers for Disease Control and Prevention, or CDC, in the 2017/2018 seasonal influenza season, only approximately 42% of the U.S. population was vaccinated against influenza, with particularly low vaccination rates among adults between ages 18 and 49.
•: Finally, we believe that utilizing our recombinant methods and production process will allow us to manufacture vaccines at scale more efficiently and within shorter time frames than conventional vaccines manufactured using traditional methods.

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Our Product Pipeline

The following table outlines the status of our oral vaccine development programs and our two marketed products:

We are developing the following tablet vaccine candidates, which are all based on our proprietary platform:

•: Norovirus Vaccine. We are developing an oral tablet vaccine for norovirus, a leading cause of acute gastroenteritis in the United States and Europe. Because norovirus infects the small intestine, we believe that our vaccine, which is designed to produce mucosal antibodies locally in the intestine in addition to systemic antibodies in the blood, will better protect against norovirus infection than an injectable vaccine.

Norovirus is the leading cause of vomiting and diarrhea from acute gastroenteritis among people of all ages in the United States. Each year, on average, norovirus causes 19 to 21 million cases of acute gastroenteritis and contributes to 56,000 to 71,000 hospitalizations and 570 to 800 deaths, mostly among young children and older adults. Typical symptoms include dehydration, vomiting, diarrhea with abdominal cramps, and nausea. In a study conducted by Pittsburg School of Medicine in 2012, the total economic burden of norovirus in the United States was estimated at $5.5 billion. In a more recent study by CDC and Johns Hopkins University, the global economic impact of norovirus disease was estimated at $60 billion, $34 billion of which occurred in high income countries including the United States, Europe and Japan. Virtually all norovirus disease is caused by norovirus GI and GII genotypes, and we are developing a bivalent vaccine designed to protect against both.

Clinical Trial Update . We have completed two Phase 1 clinical trials with our monovalent oral tablet vaccine for the GI.1 norovirus strain. The vaccine was well-tolerated and generated broad systemic and mucosal immune responses. In the clinical Phase 1b dose optimization study in healthy adults in which we evaluated four different dosing regimens, all vaccine recipients (100%) in the high dose group responded as measured by a significant increase in norovirus-specific B cells of both IgA and IgG subtypes. In the same group, there was at least a two-fold increase of norovirus-specific antibody titers in serum in more than 90% of recipients.

We plan to conduct two norovirus clinical trials during 2019, a bivalent Phase 1 study designed to assess safety and immunogenicity of our norovirus GI.1 and GII.4 vaccines administered concurrently, and a monovalent Phase 2 challenge study designed to assess the protective efficacy of our norovirus GI.1 vaccine against live norovirus GI.1 challenge in humans. The Phase 1 bivalent study and the Phase 2 challenge study will both be conducted under an open IND. Clinical protocols for both studies have been submitted to the FDA.

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The Bivalent Phase 1b Study

Manufacturing of the norovirus GII.4 and GI.1 vaccine tablets for the bivalent norovirus Phase 1b study has been completed. The bivalent norovirus vaccine Phase 1b trial consists of two parts, an open-label lead-in phase during which 5 subjects were dosed with norovirus GII.4 vaccine in March 2019, and a double-blind, placebo-controlled phase during which a total of 80 subjects will be randomized into four groups and dosed with either placebo, norovirus GI.1 vaccine, norovirus GII.4 vaccine or both norovirus vaccines. Both portions of the study are designed to evaluate safety and immunogenicity. We expect the first dosing of the randomized portion of the study to begin in April 2019. We expect to receive topline data from the Phase 1b clinical study in the second half of 2019.

The Monovalent Phase 2 Challenge Study

In addition, we remain on track to initiate the Phase 2 monovalent norovirus challenge study in the second quarter of 2019, with results expected in the second half of 2019.

In preparation for the Phase 2 challenge study, we have conducted a virus titration study to help determine the appropriate quantity of the norovirus GI.1 virus to be used to challenge patients in the study.

•: Seasonal Influenza Vaccine. Influenza is a major cause of morbidity and mortality in the U.S. and worldwide and, according to the CDC, only 42% of eligible U.S. citizens were vaccinated in 2017/2018, with particularly low vaccination rates among adults between ages 18 and 49. We believe our oral tablet vaccine has the potential to improve the protective efficacy of currently available influenza vaccines and increase flu vaccination rates.

Influenza is one of the most common global infectious diseases, causing mild to life-threatening illness and even death. It is estimated that at least 350 million cases of seasonal influenza occur annually worldwide, of which three to five million cases are considered severe, causing 290,000 to 650,000 deaths per year globally. During the most recent flu season 2017 - 2018, there were 79,400 flu related deaths in the U.S. alone, according to the CDC. Very young children and the elderly are at the greatest risk. In the United States, between 5% and 20% of the population contracts influenza, 226,000 people are hospitalized with complications of influenza, and between 3,000 and 49,000 people die from influenza and its complications each year, with up to 90% of the influenza-related deaths occurring in adults older than 65. The total economic burden of seasonal influenza has been estimated to be $87.1 billion, including medical costs which average $10.4 billion annually, while lost earnings due to illness and loss of life amount to $16.3 billion annually.

We believe our tablet vaccine candidate has the potential to address many of the limitations of current injectable egg-based influenza vaccines, because: our tablet vaccine candidates are designed to create broad and durable immune responses, which may provide more effective immunity and protect against additional strain variants; our vaccine is delivered as a room temperature-stable tablet, which should provide a more convenient method of administration to enhance patient acceptance, and should simplify distribution and administration; and, by using recombinant methods, we believe our tablet vaccine may be manufactured more rapidly than vaccines manufactured using egg-based methods and should eliminate the risk of allergic reactions to egg protein.

Clinical Trial Update . In September 2018, we completed a $15.7 million contract with the U.S. Government through the Office of Biomedical Advanced Research and Development Authority, or BARDA, under which a Phase 2 challenge study of our H1N1 flu vaccine candidate was conducted. Previously, we had announced that, in healthy volunteers immunized and then

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experimentally infected with H1 influenza, our H1 influenza oral tablet vaccine reduced clinical disease by 39% relative to placebo, a result that was superior to that of Fluzone, the market-leading injectable quadrivalent influenza vaccine, which reduced clinical disease by only 27%. Our tablet vaccine also showed a favorable safety profile, indistinguishable from placebo. On October 4, 2018, we presented data from the study demonstrating that our vaccine elicited a significant expansion of mucosal homing receptor plasmablasts to approximately 60% of all activated B cells, while Fluzone only maintained baseline levels of 20%. We believe plasmablasts are a key indicator of a protective mucosal immune response and a unique feature of our vaccines. This data also provided evidence that our vaccines protect through mucosal immunity, the first line of defense against mucosal infections such as flu, norovirus, RSV and others, a potential key advantage over injectable vaccines for these indications.

At this time, we aim to finance development and commercialization of our seasonal quadrivalent influenza oral tablet vaccine through third-party collaboration and licensing arrangements, and/or non-dilutive funding. In the future, we may also consider equity offerings and/or debt financings to fund the program.

•: HPV Therapeutic Vaccine. Our first therapeutic oral vaccine candidate targets HPV-16 and HPV-18, the two strains responsible for 70% of cervical cancers and precancerous cervical dysplasia.

Cervical cancer is the fourth most common cancer in women worldwide and in the United States with about 13,000 new cases diagnosed annually in the United States according to the National Cervical Cancer Coalition.

We have tested our HPV-16 vaccine candidate in two different HPV-16 solid tumor models in mice. The vaccine elicited T cell responses and promoted migration of the activated T cells into the tumors, leading to tumor cell killing. Mice that received our HPV-16 vaccine showed a significant reduction in volume of their established tumors.

In October 2018, we filed a pre-IND meeting request for our HPV therapeutic vaccines, VXA-HPV16.1 and VXA-HPV18.1, with the FDA, and we subsequently submitted a pre-IND briefing package. We received feedback from the FDA in January 2019 providing guidance for the IND we plan to submit. Based on this feedback, we expect to be able to file an IND for this product candidate in the course of 2019.

•: RSV Vaccine. RSV is a major respiratory pathogen with a significant burden of disease in the very young and in the elderly.

Based on the positive results of our cotton rat study, we believe our proprietary oral vaccine platform is the optimal vaccine delivery system for RSV, offering significant advantages over injectable vaccines. We aim to develop a tablet RSV vaccine by licensing one or more RSV protein antigens that have demonstrated protection against RSV infection in clinical studies, or by partnering with a third party with RSV antigens that can be delivered with our platform.

Additional Objectives

•: Develop Other Tablet Vaccine Candidates Based On Our Proprietary Platform. Our technology platform employs a modular approach using the Ad5 vector-adjuvant construct with disease-specific antigens and can be used to create new tablet vaccine candidates for a wide range of infectious diseases. We may consider exploring additional infectious diseases including RSV, Chikungunya, Hepatitis B and Herpes Simplex Virus 2, or HSV-2. In addition, we intend to leverage our vaccine formulation expertise to develop oral formulations suitable for pediatric populations.

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•: Further Strengthen Our Intellectual Property Portfolio. We intend to continue to strengthen our patent portfolio by filing and prosecuting current and future patent applications in the United States and international jurisdictions. In addition, we have established in-house formulation and tableting capabilities which we believe will allow us to further improve and optimize our proprietary techniques and know-how.
•: Maximize the Commercial Value of Our Tablet Vaccine Candidates. We believe that we own worldwide rights for the research, development, manufacturing, marketing and commercialization of our tablet vaccine candidates. As we further develop our product candidates, we may seek partners to maximize the commercial opportunity of such tablet vaccine candidates.

Anti-Virals

•: Through our merger with Aviragen Therapeutics, Inc. we acquired two royalty earning products, Relenza and Inavir, and three Phase 2 clinical stage antiviral compounds.
•: Relenza and Inavir are antivirals for the treatment of influenza that are marketed by GSK and Daiichi Sankyo, respectively. We earn royalties on the net sales of Relenza and Inavir in Japan. Sales of Relenza and Inavir vary significantly from one year to the next, depending on the intensity of the flu season and competition from other antivirals such as Tamiflu. Importantly, on February 23, 2018, Xofluza, a new drug to treat influenza developed by Shionogi, was approved in Japan. The drug may gain significant market share, substantially reducing sales of Inavir.
•: The three Phase 2 antiviral compounds obtained through the merger with Aviragen are: (i) BTA074, or teslexivir, an antiviral treatment for condyloma caused by human papillomavirus types 6 & 11; (ii) vapendavir, a capsid inhibitor for the prevention or treatment of rhinovirus upper respiratory infections; and (iii) BTA585, or enzaplatovir, a fusion protein inhibitor for the treatment of RSV infections. We have discontinued all three programs.

Recent Developments

Preliminary Unaudited First Quarter 2019 Financial Expectations

Set forth below are our expected cash and cash equivalents and long-term debt, including current portion, balances as of March 31, 2019. These preliminary results represent our estimates only and are based on currently available information and do not present all necessary information for an understanding of our financial condition as of March 31, 2019, or our results of operations for the three months ended March 31, 2019. As we complete our quarter-end financial close process and finalize our first quarter 2019 unaudited financial statements, we will be required to make significant judgments in a number of areas. This financial information has been prepared by and is the responsibility of our management. Our independent registered public accounting firm has not audited, reviewed or performed any procedures with respect to this preliminary financial data or the accounting treatment thereof and does not express an opinion or any other form of assurance with respect thereto. We expect to complete our unaudited financial statements for the quarter ended March 31, 2019 subsequent to the completion of this offering. It is possible that we or our independent registered public accounting firm may identify items that require us to make adjustments to the preliminary financial information set forth below and those changes could be material. Accordingly, undue reliance should not be placed on these preliminary estimates. These preliminary estimates are not necessarily indicative of any future period and should be read together with the sections titled "Risk Factors," "Special Note Regarding Forward-Looking Statements," and "Summary Selected Consolidated Financial Data" in this prospectus and with our financial statements, related notes and other financial information incorporated by reference in this prospectus.

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•: Total cash and cash equivalents is estimated to be approximately $8.4 million as of March 31, 2019.
•: Total long-term debt, including current portion, is estimated to be approximately $20.1 million as of March 31, 2019.

Corporate Background

Vaxart Biosciences, Inc. was originally incorporated in California in March 2004 under the name West Coast Biologicals, Inc. The Company changed its name to Vaxart, Inc. in July 2007, and reincorporated in the state of Delaware.

On February 13, 2018, we completed a business combination with Aviragen Therapeutics, Inc., or Aviragen, a publicly-traded company. Under the terms of the agreement and plan of merger and reorganization dated October 27, 2017, Vaxart, Inc. survived as a wholly owned subsidiary of Aviragen and changed its name to Vaxart Biosciences, Inc. and Aviragen changed its name to Vaxart, Inc. Our common stock subsequently began trading on the Nasdaq Capital Market under the symbol "VXRT."

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THE OFFERING


Common stock offered		5,300,000 shares
Pre-funded warrants offered		We are also offering to certain purchasers whose purchase of shares of common stock in this offering would otherwise result in the purchaser, together with its affiliates and certain related parties, beneficially owning more than 4.99% (or, at the election of the purchaser, 9.99%) of our outstanding common stock immediately following the closing of this offering, the opportunity to purchase, if such purchasers so choose, pre-funded warrants, in lieu of shares of common stock that would otherwise result in any such purchaser's beneficial ownership exceeding 4.99% (or, at the election of the purchaser, 9.99%) of our outstanding common stock. Each pre-funded warrant will be exercisable for one share of our common stock. The purchase price of each pre-funded warrant and accompanying common warrant (as described below) will equal the price at which a share of common stock and accompanying common warrant is being sold to the public in this offering, minus $0.10, and the exercise price of each pre-funded warrant will be $0.10 per share. The pre-funded warrants will be exercisable immediately and may be exercised at any time until all of the pre-funded warrants are exercised in full. This offering also relates to the shares of common stock issuable upon exercise of any pre-funded warrants sold in this offering. For each pre-funded warrant we sell, the number of shares of common stock we are offering will be decreased on a one-for-one basis. Because we will issue a common warrant for each share of our common stock and for each pre-funded warrant to purchase one share of our common stock sold in this offering, the number of common warrants sold in this offering will not change as a result of a change in the mix of the shares of our common stock and pre-funded warrants sold.
Common warrants offered by us in this offering		Common warrants to purchase an aggregate of 5,300,000 shares of our common stock. Each share of our common stock and each pre-funded warrant is being sold together with a common warrant to purchase one share of our common stock. Each common warrant will have an exercise price of $ per share, will be immediately exercisable and will expire on the fifth anniversary of the original issuance date. This prospectus also relates to the offering of the shares of common stock issuable upon exercise of the common warrants.
Option to purchase additional shares and/or common warrants		The underwriters have a 30-day option to purchase up to an additional 795,000 shares of common stock and/or common warrants to purchase up to an additional 795,000 shares of common stock from us at the public offering price less underwriting discounts and commissions.

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Common stock to be outstanding after this offering		13,641,189 shares (or 14,436,189 shares of common stock if the underwriters exercise their option to purchase additional shares in full) in each case assuming no sale of any pre-funded warrants and assuming no exercise of any common warrants issued in this offering.
Use of proceeds		We estimate that our net proceeds from this offering will be approximately $8.8 million (or approximately $10.2 million if the underwriters exercise their option to purchase additional shares and common warrants in full), based on an assumed combined public offering price of $1.90 (the last reported sale price of our common stock on the Nasdaq Capital Market on April 5, 2019), after deducting underwriting discounts and commissions and estimated offering expenses payable by us.
		We currently intend to use the net proceeds from this offering to support the clinical and preclinical development of our product candidates, to conduct clinical trials including a Phase I study with our bivalent norovirus vaccines and a Phase II challenge study with our GI.1 monovalent norovirus vaccine, to support the manufacturing of vaccines for these clinical trials, and to advance our therapeutic HPV vaccine candidate and for general corporate and working capital purposes. See the section titled "Use of Proceeds."
Risk factors		See "Risk Factors" beginning on page 11 of this prospectus, as well as other information included in this prospectus, for a discussion of factors you should read and consider carefully before investing in our securities.
Nasdaq Capital Market symbol		"VXRT." We do not intend to list the pre-funded warrants or common warrants on any securities exchange or nationally recognized trading system.

Certain of our directors and members of senior management have indicated an interest in purchasing up to an aggregate of approximately $300,000 in securities in this offering at the public offering price. However, because indications of interest are not binding agreements or commitments to purchase, the underwriters may determine to sell more, fewer or no securities in this offering to any or all of these persons, or any or all of these persons may determine to purchase more, fewer or no securities in this offering. The underwriters will receive the same underwriting discounts and commissions on any securities purchased by these persons as they will on any other securities sold to the public in this offering.

The number of shares of common stock to be outstanding after this offering is based on 7,141,189 shares of common stock outstanding as of December 31, 2018, plus 1,200,000 shares of common stock we issued and sold subsequent to December 31, 2018, and excludes:

•: 865,163 shares issuable upon the exercise of outstanding stock options with a weighted-average exercise price of $8.13 per share;
•: 10,914 shares issuable upon the exercise of an outstanding warrant with an exercise price of $22.99 per share; and
•: 223,377 shares reserved for future issuance under our 2016 Equity Incentive Plan.

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Subsequent to December 31, 2018, we issued warrants to purchase up to 84,000 shares of common stock at an exercise price of $3.125 per share to the designees of H.C. Wainwright & Co., LLC. In addition, at our annual meeting of stockholders to be held on April 23, 2019, our stockholders will be asked to approve our 2019 Equity Incentive Plan and the initial reservation of an aggregate of 1,600,000 shares thereunder.

Unless otherwise stated, information in this prospectus assumes:

•: no exercise of outstanding options or warrants;
•: no exercise by the underwriters of their option to purchase additional shares and/or common warrants; and
•: no sale of any pre-funded warrants in this offering and no exercise of the representative warrants or common warrants.

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SUMMARY SELECTED CONSOLIDATED FINANCIAL DATA

You should read the summary selected consolidated financial data below in conjunction with "Management's Discussion and Analysis of Financial Condition and Results of Operations" and the consolidated financial statements, related notes and other financial information incorporated by reference in this prospectus. The summary selected consolidated financial data in this section are not intended to replace the consolidated financial statements and are qualified in their entirety by the selected consolidated financial data included in this prospectus and the consolidated financial statements and related notes incorporated by reference in this prospectus.

The following consolidated statements of operations and comprehensive loss data for the years ended December 31, 2017 and 2018 and the consolidated balance sheet data as of December 31, 2017 and 2018 have been derived from our audited consolidated financial statements incorporated by reference in this prospectus. Our historical results are not necessarily indicative of the results that may be expected in the future.

	Year Ended December 31,

	2017			2018
	(in thousands)
Consolidated Statements of Operations and Comprehensive Loss Data:
Revenue from government contract	$	5,839		$	1,344
Royalty revenue		—			1,340
Non-cash royalty revenue related to the sale of future royalties		—			1,475

Total revenue		5,839			4,159
Operating expenses:
Research and development		12,355			17,275
General and administrative		3,499			6,681
Impairment of intangible assets		—			1,600
Costs of exit from leased premise		—			359

Total operating expenses		15,854			25,915

Operating loss		(10,015	)		(21,756	)
Total other income and (expenses)		433			3,858

Loss before provision for income taxes		(9,582	)		(17,898	)
Provision for income taxes		—			109

Net loss		(9,582	)		(18,007	)
Series B and C preferred dividend		(2,878	)		(339	)

Net loss attributable to common stockholders	$	(12,460	)	$	(18,346	)



Net loss per share—basic and diluted	$	(91.65	)	$	(2.90	)



Shares used to compute net loss per share—basic and diluted		135,953			6,316,065

	As of December 31,

	2017			2018
	(in thousands)
Consolidated Balance Sheet Data:
Cash and cash equivalents	$	1,571		$	11,506
Total assets		4,523			35,227
Long-term debt, including current portion		40,250			21,352
Total liabilities		43,245			23,989
Accumulated deficit		(79,982	)		(97,989	)
Total stockholders' (deficit) equity		(38,722	)		11,238

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RISK FACTORS

An investment in our securities involves a high degree of risk. You should carefully consider the risks described below as well as the other information in this prospectus and incorporated by reference in this prospectus before making a decision to invest in shares of our common stock or pre-funded warrants and accompanying common warrants, including the risks described under "Risk Factors" in our Annual Report on Form 10-K for the year ended December 31, 2018. Our business faces significant risks and the risks described below may not be the only risks we face. Additional risks not presently known to us or that we currently believe are immaterial may also significantly impair our business operations. If any of these risks occur, our business, results of operations or financial condition and prospects could be harmed. In that event, the market price of our common stock and the value of the pre-funded warrants could decline, and you could lose all or part of your investment.

Risks Related to this Offering

Management will have broad discretion as to the use of the net proceeds from this offering, and we may not use these proceeds effectively.

We have not designated any portion of the net proceeds from this offering to be used for any particular purposes. Our management will have broad discretion in the application of the net proceeds from this offering and could spend the proceeds in ways that do not improve our results of operations or enhance the value of our common stock. Accordingly, you will be relying on the judgment of our management with regard to the use of these net proceeds, and you will not have the opportunity, as part of your investment decision, to assess whether the proceeds are being used appropriately. Our failure to apply these funds effectively could have a material adverse effect on our business, delay the development of our products and cause the price of our common stock to decline.

You will experience immediate and substantial dilution if you purchase securities in this offering.

The price at which a share of common stock is sold in this offering will exceed the net tangible book value (deficit) per share of our common stock outstanding prior to this offering. Assuming that 5,300,000 shares of our common stock are sold in this offering, based on an assumed combined public offering price of $1.90 per share of common stock and accompanying common warrant (the last reported sale price of our common stock on the Nasdaq Capital Market on April 5, 2019), after deducting underwriting discounts and commissions and estimated offering expenses payable by us, you will experience immediate dilution of $1.67 per share, representing the difference between the price you pay and our pro forma as adjusted net tangible book value (deficit) per share as of December 31, 2018, after giving effect to this offering. See the section titled "Dilution" below for a more detailed illustration of the dilution you would incur if you participate in this offering.

Purchasers in this offering may experience additional dilution of their investment in the future.

We may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. If additional capital is raised through the sale of equity or convertible debt securities, or perceptions that those sales could occur, the issuance of these securities could result in further dilution to investors purchasing our common stock or pre-funded warrants in this offering or result in downward pressure on the price of our common stock, and our ability to raise capital in the future. In order to raise additional capital, such securities may be at prices that are not the same as the price per share in this offering. We cannot assure you that we will be able to sell shares or other securities in any other offering at a price per share that is equal to or greater than the price per share paid by investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders, including investors who purchase securities in this offering. The price per share at which

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we sell additional shares of our common stock or securities convertible into common stock in future transactions may be higher or lower than the price per share in this offering.

There is no public market for the pre-funded warrants or common warrants being offered in this offering.

There is no established public trading market for the pre-funded warrants or common warrants being offered in this offering, and we do not expect a market to develop. In addition, we do not intend to apply to list the pre-funded warrants or common warrants on any securities exchange or nationally recognized trading system, including the Nasdaq Capital Market. Without an active market, the liquidity of the pre-funded warrants and common warrants will be limited.

Holders of our pre-funded warrants and common warrants will have no rights as a common stockholder until they acquire our common stock.

Until you acquire shares of our common stock upon exercise of your pre-funded warrants or common warrants, you will have no rights with respect to shares of our common stock issuable upon exercise of your pre-funded warrants or common warrants. Upon exercise of your pre-funded warrants or common warrants, you will be entitled to exercise the rights of a common stockholder only as to matters for which the record date occurs after the exercise date.

The pre-funded warrants and common warrants are speculative in nature.

Neither the pre-funded warrants nor the common warrants offered hereby confer any rights of common stock ownership on their holders, such as voting rights or the right to receive dividends, but rather merely represent the right to acquire shares of common stock at a fixed price. Specifically, commencing on the date of issuance, holders of the pre-funded warrants may acquire the common stock issuable upon exercise of such warrants at an exercise price of $0.10 per share of common stock and holders of the common warrants may acquire the common stock issuable upon exercise of such warrants at an exercise price of $ per share. Moreover, following this offering, the market value of the pre-funded warrants and common warrants is uncertain and there can be no assurance that the market value of the pre-funded warrants or the common warrants will equal or exceed their public offering price. There can be no assurance that the market price of the common stock will ever equal or exceed the exercise price of the pre-funded warrants or common warrants, and consequently, whether it will ever be profitable for holders of the pre-funded warrants to exercise the pre-funded warrants or the holders of the common warrants to exercise the common warrants.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and the documents we have filed with the Securities and Exchange Commission, or the SEC, that are incorporated by reference contain "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933, as amended, or the Securities Act, and Section 21E of the Securities Exchange Act of 1934, or the Exchange Act. These statements relate to future events or to our future operating or financial performance and involve known and unknown risks, uncertainties and other factors which may cause our actual results, performance or achievements to be materially different from any future results, performances or achievements expressed or implied by the forward-looking statements. Forward-looking statements may include, but are not limited to, statements about:

•: our ability to fund our working capital requirements;
•: the amount and timing of royalties received on sales of Relenza and Inavir;
•: the timing and costs of our planned clinical trials for our product candidates, both tablet vaccines and small-molecule antiviral drugs;
•: our ability to obtain and maintain regulatory approval of our product candidates;
•: our ability to establish and scale commercial manufacturing capabilities;
•: the rate and degree of market acceptance of our products, if any, that are approved;
•: our estimates of our expenses, ongoing losses, future revenue, capital requirements and our needs for or ability to obtain additional financing;
•: our ability to obtain and maintain intellectual property protection for our product candidates;
•: our ability to identify and develop new product candidates and the number and characteristics of product candidates that we pursue;
•: our ability to retain and recruit key personnel;
•: our planned use of the proceeds from this offering;
•: our financial performance;
•: our ability to become profitable and generate consistent cash flows to remain profitable;
•: developments and projections relating to our competitors or our industry; and
•: our expected use of the net proceeds from this offering.

In some cases, you can identify forward-looking statements by terms such as "anticipates," "believes," "could," "estimates," "intends," "may," "plans," "potential," "will," "would," or the negative of these terms or other similar expressions. These statements reflect our current views with respect to future events and are based on assumptions and are subject to risks and uncertainties. Given these uncertainties, you should not place undue reliance on these forward-looking statements. We discuss in greater detail many of these risks in the section titled "Risk Factors", in any free writing prospectuses we may authorize for use in connection with this offering, and in our most recent Annual Report on Form 10-K, as well as any amendments thereto reflected in subsequent filings with the SEC, which are incorporated by reference into this prospectus in their entirety. Also, these forward-looking statements represent our estimates and assumptions only as of the date of the document containing the applicable statement. Unless required by law, we undertake no obligation to update or revise any forward-looking statements to reflect new information or future events or developments.

In addition, statements that "we believe" and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this

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prospectus, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and investors are cautioned not to unduly rely upon these statements.

You should read this prospectus, together with the documents we have filed with the SEC that are incorporated by reference and any free writing prospectus that we may authorize for use in connection with this offering completely and with the understanding that our actual future results may be materially different from what we expect. We qualify all of the forward-looking statements in the foregoing documents by these cautionary statements.

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MARKET AND INDUSTRY DATA

This prospectus and the documents incorporated by reference in this prospectus contain market data and industry statistics and forecasts that are based on independent industry publications and other publicly available information. Although we believe that these sources are reliable, we do not guarantee the accuracy or completeness of this information and we have not independently verified this information. Although we are not aware of any misstatements regarding the market and industry data presented or incorporated by reference in this prospectus, these estimates involve risks and uncertainties and are subject to change based on various factors, including those discussed in the section titled "Risk Factors" and any related free writing prospectus. Accordingly, investors should not place undue reliance on this information.

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USE OF PROCEEDS

We estimate that our net proceeds from the sale of 5,300,000 shares of common stock in this offering will be approximately $8.8 million, based on an assumed combined public offering price of $1.90 per share of common stock and accompanying common warrant (the last reported sale price of our common stock on the Nasdaq Capital Market on April 5, 2019), after deducting underwriting discounts and commissions and estimated offering expenses payable by us. If the underwriters exercise their option to purchase 795,000 additional shares of common stock together with accompanying common warrants to purchase up to 795,000 shares of common stock in full, we estimate that our net proceeds from this offering will be approximately $10.2 million, after deducting underwriting discounts and commissions and estimated offering expenses payable by us. We cannot predict when or if the common warrants will be exercised. It is possible that the common warrants may expire and may never be exercised.

A $0.50 increase (decrease) in the assumed combined public offering price of $1.90 per share of common stock and accompanying common warrant (the last reported sale price of our common stock on the Nasdaq Capital Market on April 5, 2019), would increase (decrease) the expected net cash proceeds of the offering to us by $2.5 million, assuming that the number of shares offered by us, as set forth on the cover page of this prospectus remains the same, after deducting underwriting discounts and commissions and estimated offering expenses payable by us. An increase (decrease) of 1.0 million shares in the number of shares of common stock offered by us would increase (decrease) the net proceeds to us from this offering by $1.8 million, assuming that the assumed combined public offering price of $1.90 per share of common stock and accompanying common warrant remains the same, after deducting underwriting discounts and commissions and estimated offering expenses payable by us.

We currently intend to use the net proceeds from this offering to support the clinical and preclinical development of our product candidates, to conduct clinical trials, including a Phase I study with our bivalent norovirus vaccines and a Phase II challenge study with our GI.1 monovalent norovirus vaccine, to support the manufacturing of vaccines for these clinical trials and to advance our therapeutic HPV vaccine candidate, and for general corporate and working capital purposes. Accordingly, we retain broad discretion to use of these proceeds.

Pending the use of the net proceeds from this offering, we intend to invest the net proceeds in investment-grade, interest-bearing instruments.

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DIVIDEND POLICY

We have never paid or declared any cash dividends on our common stock. We do not anticipate paying any cash dividends on our common stock in the foreseeable future, and we intend to retain all available funds and any future earnings to fund the development and expansion of our business. In addition, covenants in the agreement governing our senior secured credit facility do not allow for the payment of any cash dividends. Any future determination to pay dividends will be at the discretion of our board of directors and will depend upon a number of factors, including our results of operations, financial condition, future prospects, contractual restrictions, restrictions imposed by applicable law and other factors our board of directors deems relevant.

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CAPITALIZATION

The following table shows our cash and cash equivalents and our capitalization as of December 31, 2018 on:

•: an actual basis;
•: a pro forma basis giving effect to the sale by us of 1,200,000 shares of common stock subsequent to December 31, 2018 at a price of $2.50 per share, after deducting placement agent fees and estimated offering expenses payable by us; and
•: a pro forma as adjusted basis, giving further effect to the sale by us of 5,300,000 shares of common stock in this offering at the assumed combined public offering price of $1.90 per share (the last reported sale price of our common stock on the Nasdaq Capital Market on April 5, 2019), after deducting underwriting discounts and commissions and estimated offering expenses payable by us.

	As of December 31, 2018

	Actual			Pro Forma			Pro Forma As Adjusted(1)
	(in thousands, except share and per share data)
Cash and cash equivalents	$	11,506		$	13,996		$	22,761



Long-term debt, including current portion	$	21,352		$	21,352		$	21,352
Stockholders' equity:
Preferred stock, $0.10 par value, 5,000,000 shares authorized, no shares issued and outstanding, actual, pro forma and pro forma as adjusted		—			—			—
Common stock, $0.10 par value, 200,000,000 shares authorized, 7,141,189 shares issued and outstanding, actual; 8,341,189 shares issued and outstanding, pro forma; 13,641,189 shares issued and outstanding, pro forma as adjusted		714			834			1,364
Additional paid-in capital		108,513			110,883			119,118
Accumulated other comprehensive income		—			—			—
Accumulated deficit		(97,989	)		(97,989	)		(97,989	)

Total stockholders' equity		11,238			13,728			22,493

Total capitalization	$	32,590		$	35,080		$	43,845

(1): A $0.50 increase (decrease) in the assumed combined public offering price of $1.90 per share of common stock and accompanying common warrant (the last reported sale price of our common stock on the Nasdaq Capital Market on April 5, 2019), would increase (decrease) each of cash and cash equivalents, additional paid-in capital, total stockholders' equity and total capitalization by $2.5 million, assuming that the number of shares offered by us, as set forth on the cover page of this prospectus remains the same, after deducting underwriting discounts and commissions and estimated offering expenses payable by us. An increase (decrease) of 1.0 million shares in the number of shares of common stock offered by us would increase (decrease) each of cash and cash equivalents, additional paid-in capital, total stockholders' equity and total capitalization by $1.8 million, assuming that the assumed public offering price of $1.90 per share of common stock and accompanying warrant remains the same, after deducting underwriting discounts and

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commissions and estimated offering expenses payable by us. The as adjusted information discussed above is illustrative only and will be adjusted based on the actual public offering price and other terms of this offering determined at pricing.

The number of shares of common stock in the table above excludes:

•: 865,163 shares issuable upon the exercise of outstanding stock options with a weighted-average exercise price of $8.13 per share;
•: 10,914 shares issuable upon the exercise of an outstanding warrant with an exercise price of $22.99 per share; and
•: 223,377 shares reserved for future issuance under our 2016 Equity Incentive Plan.

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DILUTION

If you purchase securities in this offering, your interest will be diluted to the extent of the difference between the combined public offering price per share and the pro forma as adjusted net tangible book value per share of our common stock after this offering, assuming no value is attributed to the pre-funded warrants, and such pre-funded warrants are accounted for and classified as equity.

As of December 31, 2018, our pro forma net tangible book value (deficit) was $(5.7) million, or $(0.68) per share (after giving effect to the sale of 1,200,000 shares of common stock subsequent to December 31, 2018). Net tangible book value (deficit) is total tangible assets less total liabilities divided by the total number of outstanding shares of common stock.

After giving effect to the sale of 5,300,000 shares of common stock and accompanying common warrants in this offering at an assumed combined public offering price of $1.90 per share and accompanying common warrant, (the last reported sale price of our common stock on the Nasdaq Capital Market on April 5, 2019), after deducting underwriting discounts and commissions and estimated offering expenses payable by us, our pro forma as adjusted net tangible book value as of December 31, 2018, would have been $3.1 million, or $0.23 per share. This represents an immediate increase in pro forma as adjusted net tangible book value of $0.91 per share to our existing stockholders and immediate dilution in net tangible book value of $1.67 per share to investors participating in this offering. The following table illustrates this dilution per share to investors participating in this offering:


Assumed combined public offering price per share and accompanying common warrant				$	1.90
Pro forma net tangible book value (deficit) per share as of December 31, 2018	$	(0.68	)
Increase in pro forma as adjusted net tangible book value per share attributable to new investors in this offering		0.91

Pro forma as adjusted net tangible book value per share after giving effect to this offering					0.23

Dilution in net tangible book value per share to new investors in this offering				$	1.67

A $0.50 increase (decrease) in the assumed combined public offering price of $1.90 per share of common stock and accompanying common warrant would increase (decrease), respectively, our pro forma as adjusted net tangible book value after this offering by $0.18 per share, and dilution per share to new investors by $0.32 per share, assuming that the number of shares of common stock offered by us, as set forth above, remains the same, after deducting underwriting discounts and commissions and estimated offering expenses payable by us. We may also increase or decrease the number of shares of common stock we are offering. An increase of 1.0 million shares of common stock in the number of shares of common stock offered by us would increase our pro forma as adjusted net tangible book value after this offering by $0.11 per share, and dilution per share to new investors would decrease by $0.11 per share, assuming that the assumed public offering price remains the same, after deducting underwriting discounts and commissions and estimated offering expenses payable by us. A decrease of 1.0 million shares in the number of shares of common stock offered by us would decrease our pro forma as adjusted net tangible book value after this offering by $0.12 per share, and dilution per share to new investors would increase by $0.12 per share, assuming that the assumed combined public offering price of the common stock and accompanying warrant remains the same, after deducting underwriting discounts and commissions and estimated offering expenses payable by us.

The information discussed above is illustrative only and will adjust based on the actual combined public offering price of the common stock and accompanying warrant, the actual number of shares that we offer in this offering, and other terms of this offering determined at pricing. The discussion and table above assume (i) no sale of pre-funded warrants, which, if sold, would reduce the number of

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shares of common stock that we are offering on a one-for-one basis, (ii) no exercise of the underwriter's option to purchase up to an additional 795,000 shares of common stock and/or common warrants to purchase up to an additional 795,000 shares of our common stock and (iii) no exercise of common warrants accompanying the shares of common stock and pre-funded warrants, if any, sold in this offering.

If the underwriters exercise in full their option to purchase up to 795,000 additional shares of common stock together with accompanying common warrants to purchase up to an additional 795,000 shares of common stock, our pro forma as adjusted net tangible book value after this offering would be $0.31 per share, representing an increase in pro forma as adjusted net tangible book value of $0.99 per share to existing stockholders and immediate dilution in net tangible book value of $1.59 per share to new investors in this offering.

If investors in this offering exercise in full the common warrants for 5,300,000 share of common stock offered hereby for cash at an assumed exercise price of $1.90 per share (the last reported sale price of our common stock on the Nasdaq Capital Market on April 5, 2019), our pro forma as adjusted net tangible book value after this offering would be $0.69 per share, representing an increase in pro forma as adjusted net tangible book value of $1.37 per share and immediate dilution in net tangible book value of $1.21 per share to new investors in this offering.

•: 865,163 shares issuable upon the exercise of outstanding stock options with a weighted-average exercise price of $8.13 per share;
•: 10,914 shares issuable upon the exercise of an outstanding warrant with an exercise price of $22.99 per share; and
•: 223,377 shares reserved for future issuance under our 2016 Equity Incentive Plan.

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PRINCIPAL STOCKHOLDERS

The following table sets forth, as of December 31, 2018, information regarding beneficial ownership of our common stock by:

•: each stockholder known by us to beneficially own more than 5% of our outstanding common stock;
•: each of our current named executive officers as set forth in our Annual Report on Form 10-K for the year ended December 31, 2018;
•: each of our directors; and
•: all of our current executive officers and directors as a group.

Beneficial ownership is determined according to the rules of the SEC and generally means that a person has beneficial ownership of a security if he, she or it possesses sole or shared voting or investment power of that security, including options that are currently exercisable or exercisable within 60 days of December 31, 2018. Except as indicated by the footnotes below, we believe, based on the information furnished to us, that the persons named in the table below have sole voting and investment power with respect to all shares of common stock shown that they beneficially own.

Our calculation of the percentage of beneficial ownership before this offering is based on 7,141,189 shares of our common stock outstanding as of December 31, 2018, plus an additional 1,200,000 shares of common stock we issued and sold subsequent to December 31, 2018. We have based our calculation of the percentage of beneficial ownership after this offering on 13,641,189 shares of our common stock to be outstanding immediately after the closing of this offering, assuming no exercise of the pre-funded warrants, the common warrants or the representative warrants, and assuming no exercise by the underwriters of their option to purchase additional shares and/or common warrants.

Common stock subject to stock options currently exercisable or exercisable within 60 days of December 31, 2018, are deemed to be outstanding for computing the percentage ownership of the person holding these options and the percentage ownership of any group of which the holder is a member but are not deemed outstanding for computing the percentage of any other person.

Certain of our directors and members of senior management have indicated an interest in purchasing up to an aggregate of approximately $300,000 in securities in this offering at the public offering price. However, because indications of interest are not binding agreements or commitments to purchase, the underwriters may determine to sell more, fewer or no securities in this offering to any or all of these persons, or any or all of these persons may determine to purchase more, fewer or no securities in this offering. The table below assumes no purchases of securities by these persons.

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Unless otherwise noted below, the address for each of the stockholders in the table below is c/o Vaxart, Inc., 290 Utah Ave, Suite 200, South San Francisco, California 94080.

	Beneficial Ownership

Name of Beneficial Owner	Shares		Before Offering			After Offering
Greater than 5% Stockholders:
Entities affiliated with Care Capital(1)		2,799,424		33.6	%		20.5	%
Executive Officers and Directors:
Geoffrey F. Cox, Ph.D.(2)		8,567		*			*
Michael J. Finney, Ph.D.		270,754		3.2			2.0
John M. Harland(3)		23,636		*			*
Wouter W. Latour, M.D.(4)		78,051		*			*
Richard J. Markham(5)		—		*			*
John P. Richard(6)		9,543		*			*
Sean N. Tucker, Ph.D.(7)		130,710		1.6			*
Anne M. VanLent(8)		12,724		*			*
All executive officers and directors as a group (8 persons)		533,985		6.3			3.9	%

*: Represents beneficial ownership of less than one percent.
(1): Includes (a) 2,753,441 shares held by Care Capital Investments III, LP ("Investments III") and (b) 45,983 shares held by Care Capital Offshore Investments III, LP ("Offshore III"). Care Capital III LLC is the general partner of Investments III LP and Offshore III (collectively, "Care Capital") and as a result, Care Capital III LLC has the ultimate power to vote or direct the vote and to dispose or direct the disposition of such shares. The address for each of these entities is P.O. Box 276, Avon by the Sea, New Jersey 07717.
(2): Includes (a) 388 shares held by Dr. Cox's spouse, and (b) 8,179 shares issuable pursuant to stock options exercisable within 60 days of December 31, 2018.
(3): Includes (a) 761 shares held directly by Mr. Harland, and (b) 22,875 shares issuable pursuant to stock options exercisable within 60 days of December 31, 2018.
(4): Consists of 78,051 shares issuable pursuant to stock options exercisable within 60 days of December 31, 2018.
(5): Mr. Markham ceased to serve as a managing member of Care Capital effective December 31, 2018, and does not beneficially own any shares.
(6): Consists of 9,543 shares issuable pursuant to stock options exercisable within 60 days of December 31, 2018.
(7): Includes (a) 47,653 shares held directly by Dr. Tucker, (b) 25,388 shares held by Frances Chang and Sean Tucker, (c) 9,060 shares held by Dr. Tucker's spouse, and (d) 48,609 shares issuable pursuant to stock options exercisable within 60 days of December 31, 2018.
(8): Includes (a) 3,181 shares held directly by Ms. VanLent, and (b) 9,543 shares issuable pursuant to stock options exercisable within 60 days of December 31, 2018.

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DESCRIPTION OF CAPITAL STOCK

The following summary description of our capital stock is based on the provisions of our amended and restated certificate of incorporation and amended and restated bylaws and the applicable provisions of the Delaware General Corporation Law. This information is qualified entirely by reference to the applicable provisions of our amended and restated certificate of incorporation, bylaws and the Delaware General Corporation Law. For information on how to obtain copies of our amended and restated certificate of incorporation and bylaws, which are exhibits to the registration statement of which this prospectus is a part, see the sections titled "Where You Can Find Additional Information" and "Incorporation of Certain Information by Reference" in this prospectus.

General

Our authorized capital stock consists of (i) 200,000,000 shares of common stock, par value $0.10 per share and (ii) 5,000,000 shares of preferred stock, par value $0.10 per share. At our annual meeting of stockholders to be held on April 23, 2019, our stockholders will be asked to approve an amendment to our amended and restated certificate of incorporation to decrease our authorized shares of common stock from 200,000,000 to 100,000,000 shares.

As of December 31, 2018, there were 7,141,189 shares of common stock issued and outstanding, and no shares of preferred stock outstanding. Subsequent to December 31, 2018, we issued and sold 1,200,000 shares of common stock.

The following is a summary of the material provisions of the common stock and preferred stock provided for in our amended and restated certificate of incorporation and amended and restated bylaws.

Common Stock

Voting

Our common stock is entitled to one vote for each share held of record on all matters submitted to a vote of the stockholders, except that directors will be elected by a plurality of votes cast. Accordingly, the holders of a majority of the shares of common stock entitled to vote in any election of directors are able to elect all of the directors standing for election, if they so choose.

Dividends

Subject to preferences that may be applicable to any then outstanding preferred stock, the holders of common stock are entitled to receive dividends, if any, as may be declared from time to time by our board of directors out of legally available funds. We have never paid cash dividends and have no present intention to pay cash dividends.

Liquidation

In the event of a liquidation, dissolution or winding up, holders of our common stock will be entitled to share ratably in the net assets legally available for distribution to stockholders after the payment of all of our debts and other liabilities, subject to the satisfaction of any liquidation preference granted to the holders of any outstanding shares of preferred stock.

Rights and Preferences

Holders of our common stock have no preemptive, conversion or subscription rights, and there are no redemption or sinking fund provisions applicable to our common stock. The rights, preferences and privileges of the holders of our common stock are subject to, and may be adversely affected by, the

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rights of the holders of shares of any series of our preferred stock that we may designate and issue in the future.

Fully Paid and Nonassessable

All of our outstanding shares of common stock are fully paid and nonassessable.

Preferred Stock

Our board of directors has the authority, without further action by the stockholders, to issue up to 5,000,000 shares of preferred stock in one or more series, to establish from time to time the number of shares to be included in each such series, to fix the rights, preferences and privileges of the shares of each wholly unissued series and any qualifications, limitations or restrictions thereon and to increase or decrease the number of shares of any such series, but not below the number of shares of such series then outstanding.

Our board of directors may authorize the issuance of preferred stock with voting or conversion rights that could adversely affect the voting power or other rights of the holders of the common stock. The issuance of preferred stock, while providing flexibility in connection with possible acquisitions and other corporate purposes, could, among other things, have the effect of delaying, deferring or preventing a change in our control that may otherwise benefit holders of our common stock and may adversely affect the market price of the common stock and the voting and other rights of the holders of common stock. As of December 31, 2018, there were no shares of preferred stock outstanding and we have no current plans to issue any shares of preferred stock.

Anti-Takeover Effects of Provisions of Our Charter Documents and Delaware Law

Delaware Anti-Takeover Law

We are subject to Section 203 of the DGCL, or Section 203. Section 203 generally prohibits a public Delaware corporation from engaging in a "business combination" with an "interested stockholder" for a period of three years after the date of the transaction in which the person became an interested stockholder, unless:

•: prior to the date of the transaction, the board of directors of the corporation approved either the business combination or the transaction which resulted in the stockholder becoming an interested stockholder;
•: the interested stockholder owned at least 85% of the voting stock of the corporation outstanding upon consummation of the transaction, excluding for purposes of determining the number of shares outstanding (1) shares owned by persons who are directors and also officers and (2) shares owned by employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or
•: on or subsequent to the consummation of the transaction, the business combination is approved by the board and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of at least 66 ² ^/ ³ % of the outstanding voting stock which is not owned by the interested stockholder.
•: Section 203 defines a business combination to include:
•: any merger or consolidation involving the corporation and the interested stockholder;
•: any sale, transfer, pledge or other disposition involving the interested stockholder of 10% or more of the assets of the corporation;

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•: subject to exceptions, any transaction involving the corporation that has the effect of increasing the proportionate share of the stock of any class or series of the corporation beneficially owned by the interested stockholder;
•: subject to exceptions, any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder; and
•: the receipt by the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits provided by or through the corporation.

In general, Section 203 defines an interested stockholder as any entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by the entity or person.

Certificate of Incorporation and Bylaws

Provisions of our certificate of incorporation and bylaws may delay or discourage transactions involving an actual or potential change-in-control or change in our management, including transactions in which stockholders might otherwise receive a premium for their shares or transactions that our stockholders might otherwise deem to be in their best interests. Therefore, these provisions could adversely affect the price of our common stock. Among other things, our certificate of incorporation and bylaws:

•: permit our board of directors to issue up to 5,000,000 shares of preferred stock, with any rights, preferences and privileges as they may designate (including the right to approve an acquisition or other change in control);
•: provide that the authorized number of directors may be changed only by resolution adopted by a majority of the board of directors;
•: provide that all vacancies, including newly created directorships, may, except as otherwise required by law or subject to the rights of holders of preferred stock as designated from time to time, be filled by the affirmative vote of a majority of directors then in office, even if less than a quorum;
•: require that any action to be taken by our stockholders must be effected at a duly called annual or special meeting of stockholders or by action taken by written consent;
•: provide that stockholders seeking to present proposals before a meeting of stockholders or to nominate candidates for election as directors at a meeting of stockholders must provide notice in writing in a timely manner and also specify requirements as to the form and content of a stockholder's notice; and
•: provide that special meetings of our stockholders may be called only by the chairman of the board, the president or by our board of directors pursuant to a resolution adopted by a majority of the total number of authorized directors (whether or not there exist any vacancies).

Nasdaq Capital Market Listing

Our common stock is listed on the Nasdaq Capital Market under the symbol "VXRT."

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is American Stock Transfer & Trust Company, LLC. The transfer agent and registrar's address is 6201 15th Avenue, Brooklyn, New York 11219.

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DESCRIPTION OF SECURITIES WE ARE OFFERING

We are offering 5,300,000 shares of our common stock and/or pre-funded warrants and accompanying common warrants to purchase up to 5,300,000 shares of our common stock. Each share of common stock or pre-funded warrant is being sold together with a common warrant to purchase one share of common stock. The shares of common stock, pre-funded warrants and common warrants will be issued separately. We are also registering the shares of common stock issuable from time to time upon exercise of the pre-funded warrants and common warrants offered hereby.

Common Stock

The material terms and provisions of our common stock and each other class of our securities which qualifies or limits our common stock are described under the caption "Description of Capital Stock" in this prospectus.

Pre Funded Warrants

The following summary of certain terms and provisions of pre-funded warrants that are being offered hereby is not complete and is subject to, and qualified in its entirety by, the provisions of the pre-funded warrant, the form of which is filed as an exhibit to the registration statement of which this prospectus forms a part. Prospective investors should carefully review the terms and provisions of the form of pre-funded warrant for a complete description of the terms and conditions of the pre-funded warrants.

Duration and Exercise Price. Each pre-funded warrant offered hereby will have an initial exercise price per share equal to $0.10. The pre-funded warrants will be immediately exercisable and may be exercised at any time until the pre-funded warrants are exercised in full. The exercise price and number of shares of common stock issuable upon exercise is subject to appropriate adjustment in the event of stock dividends, stock splits, reorganizations or similar events affecting our common stock and the exercise price. The pre-funded warrants will be issued separately from the accompanying common warrants, and may be transferred separately immediately thereafter.

Exercisability. The pre-funded warrants will be exercisable, at the option of each holder, in whole or in part, by delivering to us a duly executed exercise notice accompanied by payment in full for the number of shares of our common stock purchased upon such exercise (except in the case of a cashless exercise as discussed below). A holder (together with its affiliates) may not exercise any portion of the pre-funded warrant to the extent that the holder would own more than 4.99% of the outstanding common stock immediately after exercise, except that upon at least 61 days' prior notice from the holder to us, the holder may increase the amount of ownership of outstanding stock after exercising the holder's pre-funded warrants up to 9.99% of the number of shares of our common stock outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the pre-funded warrants. Purchasers of pre-funded warrants in this offering may also elect prior to the issuance of the pre-funded warrants to have the initial exercise limitation set at 9.99% of our outstanding common stock. No fractional shares of common stock will be issued in connection with the exercise of a pre-funded warrant. In lieu of fractional shares, we will either pay the holder an amount in cash equal to the fractional amount multiplied by the exercise price or round up to the next whole share.

Cashless Exercise. If, at the time a holder exercises its pre-funded warrants, a registration statement registering the issuance of the shares of common stock underlying the pre-funded warrants under the Securities Act is not then effective or available, then in lieu of making the cash payment otherwise contemplated to be made to us upon such exercise in payment of the aggregate exercise price, the holder may elect instead to receive upon such exercise (either in whole or in part) the net

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number of shares of common stock determined according to a formula set forth in the pre-funded warrants.

Transferability. Subject to applicable laws, a pre-funded warrant may be transferred at the option of the holder upon surrender of the pre-funded warrant to us together with the appropriate instruments of transfer.

Exchange Listing. There is no trading market available for the pre-funded warrants on any securities exchange or nationally recognized trading system. We do not intend to list the pre-funded warrants on any securities exchange or nationally recognized trading system.

Right as a Stockholder. Except as otherwise provided in the pre-funded warrants or by virtue of such holder's ownership of shares of our common stock, the holders of the pre-funded warrants do not have the rights or privileges of holders of our common stock, including any voting rights, until they exercise their pre-funded warrants.

Fundamental Transaction. In the event of a fundamental transaction, as described in the pre-funded warrants and generally including any reorganization, recapitalization or reclassification of our common stock, the sale, transfer or other disposition of all or substantially all of our properties or assets, our consolidation or merger with or into another person, the acquisition of more than 50% of our outstanding common stock, or any person or group becoming the beneficial owner of 50% of the voting power represented by our outstanding common stock, the holders of the pre-funded warrants will be entitled to receive upon exercise of the pre-funded warrants the kind and amount of securities, cash or other property that the holders would have received had they exercised the pre-funded warrants immediately prior to such fundamental transaction. Notwithstanding the foregoing, in the event of a fundamental transaction, the holders will have the option, which may be exercised within 30 days after the consummation of the fundamental transaction, to require us or our successor entity to purchase the common warrants from the holder by paying to the holder an amount of cash equal to the Black Scholes value of the remaining unexercised portion of the common warrant on the date of the consummation of the fundamental transaction. However, if the fundamental transaction is not within our control, including not approved by our board of directors, the holder will only be entitled to receive from us or our successor entity, as of the date of consummation of such fundamental transaction, the same type or form of consideration (and in the same proportion), at the Black Scholes value of the unexercised portion of the common warrant, that is being offered and paid to the holders of common stock in connection with the fundamental transaction, whether that consideration be in the form of cash, stock or any combination thereof, or whether the holders of common stock are given the choice to receive from among alternative forms of consideration in connection with the fundamental transaction.

Common Warrants

The following summary of certain terms and provisions of common warrants that are being offered hereby is not complete and is subject to, and qualified in its entirety by, the provisions of the common warrants, the form of which is filed as an exhibit to the registration statement of which this prospectus forms a part. Prospective investors should carefully review the terms and provisions of the form of common warrant for a complete description of the terms and conditions of the common warrants.

Duration and Exercise Price. Each common warrant offered hereby will have an initial exercise price per share equal to $ . The common warrants will be immediately exercisable and will expire on the fifth anniversary of the original issuance date. The exercise price and number of shares of common stock issuable upon exercise is subject to appropriate adjustment in the event of stock dividends, stock splits, reorganizations or similar events affecting our common stock and the exercise price. The common warrants will be issued separately from the common stock, and may be transferred

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separately immediately thereafter. A common warrant to purchase one share of our common stock will be issued for every one share of common stock or pre-funded warrant purchased in this offering.

Exercisability. The common warrants will be exercisable, at the option of each holder, in whole or in part, by delivering to us a duly executed exercise notice accompanied by payment in full for the number of shares of our common stock purchased upon such exercise (except in the case of a cashless exercise as discussed below). A holder (together with its affiliates) may not exercise any portion of the common warrant to the extent that the holder would own more than 4.99% of the outstanding common stock immediately after exercise, except that upon at least 61 days' prior notice from the holder to us, the holder may increase the amount of ownership of outstanding stock after exercising the holder's common warrants up to 9.99% of the number of shares of our common stock outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the common warrants. Purchasers in this offering may also elect prior to the issuance of the common warrants to have the initial exercise limitation set at 9.99% of our outstanding common stock. No fractional shares of common stock will be issued in connection with the exercise of a common warrant. In lieu of fractional shares, we will either pay the holder an amount in cash equal to the fractional amount multiplied by the exercise price or round up to the next whole share.

Cashless Exercise. If, at the time a holder exercises its common warrants, a registration statement registering the issuance of the shares of common stock underlying the common warrants under the Securities Act is not then effective or available and an exemption from registration under the Securities Act is not available for the issuance of such shares, then in lieu of making the cash payment otherwise contemplated to be made to us upon such exercise in payment of the aggregate exercise price, the holder may elect instead to receive upon such exercise (either in whole or in part) the net number of shares of common stock determined according to a formula set forth in the common warrants.

Transferability. Subject to applicable laws, a common warrant may be transferred at the option of the holder upon surrender of the common warrant to us together with the appropriate instruments of transfer.

Exchange Listing. There is no trading market available for the common warrants on any securities exchange or nationally recognized trading system. We do not intend to list the common warrants on any securities exchange or nationally recognized trading system.

Right as a Stockholder. Except as otherwise provided in the common warrants or by virtue of such holder's ownership of shares of our common stock, the holders of the common warrants do not have the rights or privileges of holders of our common stock, including any voting rights, until they exercise their common warrants.

Fundamental Transaction. In the event of a fundamental transaction, as described in the common warrants and generally including any reorganization, recapitalization or reclassification of our common stock, the sale, transfer or other disposition of all or substantially all of our properties or assets, our consolidation or merger with or into another person, the acquisition of more than 50% of our outstanding common stock, or any person or group becoming the beneficial owner of 50% of the voting power represented by our outstanding common stock, the holders of the common warrants will be entitled to receive upon exercise of the common warrants the kind and amount of securities, cash or other property that the holders would have received had they exercised the common warrants immediately prior to such fundamental transaction.

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UNDERWRITING

We have entered into an underwriting agreement with H.C. Wainwright & Co., LLC as the sole book-running manager of this offering. Subject to the terms and conditions of the underwriting agreement, we have agreed to sell to the underwriters, and the underwriters have agreed to purchase from us, shares of our common stock and/or pre-funded warrants and accompanying common warrants to purchase shares of our common stock. Our common stock is listed on the Nasdaq Capital Market under the symbol "VXRT".

Pursuant to the terms and subject to the conditions contained in the underwriting agreement, we have agreed to sell to the underwriters named below, and the underwriters have agreed to purchase from us, the respective number of shares of common stock, pre-funded warrants and common warrants to purchase common stock set forth opposite their name below:

Underwriter

H.C. Wainwright & Co., LLC
CIM Securities, LLC

Total	5,300,000	5,300,000

The underwriting agreement provides that the obligation of the underwriters to purchase the shares of common stock and/or pre-funded warrants and common warrants to purchase shares of common stock offered by this prospectus is subject to certain conditions. The underwriters are obligated to purchase all of the shares of common stock and/or pre-funded warrants and common warrants to purchase shares of our common stock offered hereby if any of the securities are purchased, other than those shares covered by the option to purchase additional shares and/or common warrants described below.

Option to Purchase Additional Shares

We have granted the underwriters an option to purchase additional securities. This option, which is exercisable for up to 30 days after the date of this prospectus, permits the underwriters to purchase up to 795,000 shares of common stock at a price of $ per share, and/or common warrants exercisable for up to 795,000 shares of common stock at a price of $0.01 per common warrant, less underwriting discounts and commissions.

Discounts, Commissions and Expenses

The underwriters propose to offer the shares of common stock and/or pre-funded warrants and accompanying common warrants to purchase shares of our common stock pursuant to the underwriting agreement to the public at the combined public offering price set forth on the cover page of this prospectus and to certain dealers at that price less a concession not in excess of $ per share and accompanying common warrant or $ per pre-funded warrant and accompanying common warrant, based on the combined public offering price per share and accompanying common warrant or pre-funded warrant and accompanying common warrant set forth on the cover page of this prospectus. After this offering, the public offering price and concession may be changed by the underwriters. No such change shall change the amount of proceeds to be received by us as set forth on the cover page of this prospectus.

In connection with the sale of the common stock and/or pre-funded warrants and accompanying common warrants to purchase shares of our common stock to be purchased by the underwriters, the

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underwriters will be deemed to have received compensation in the form of underwriting discounts and commissions. The underwriting discounts and commissions will be 7% of the gross proceeds of this offering, or $ per share of common stock and accompanying common warrant or per pre-funded warrant and accompanying common warrant.

The following table shows underwriting discounts and commissions payable to the underwriters by us in connection with this offering:

				Total

	Per Share	Per Pre-Funded Warrant	Per Common Warrant	No Exercise	Full Exercise
Public offering price	$	$	$	$	$
Underwriting discounts and commissions payable by us	$	$	$	$	$

We have also agreed to reimburse H.C. Wainwright & Co., LLC for reasonable out-of-pocket expenses, including legal fees and expenses, of up to $40,000. We estimate the total expenses payable by us for this offering will be approximately $600,000, which amount excludes underwriting discounts and commissions.

Representative Warrants

In addition, we have agreed to issue to H.C. Wainwright & Co., LLC warrants to purchase up to shares of common stock (which represents 7% of the aggregate number of shares of common stock sold in this offering (including the number of shares of common stock issuable upon exercise of the pre-funded warrants and the underwriters' option to purchase additional shares of common stock if exercised) at an exercise price of $ per share of common stock (representing 125% of the combined public offering price per share of common stock to be sold in this offering). The warrants will each have a term of five years from the effective date of the registration statement of which this prospectus forms a part. Pursuant to the Financial Industry Regulatory Authority, Inc., or FINRA, Rule 5110(g), the warrants and any shares of common stock issued upon exercise of the warrants may not be sold, transferred, assigned, pledged or hypothecated, or be the subject of any hedging, short sale, derivative, put or call transaction that would result in the effective economic disposition of the securities by any person for a period of 180 days immediately following the date of effectiveness or commencement of sales of this offering, except the transfer of any security: (i) by operation of law or by reason of our reorganization; (ii) to any FINRA member firm participating in the offering and the officers or partners thereof, if all securities so transferred remain subject to the lock-up restriction set forth above for the remainder of the time period; (iii) if the aggregate amount of our securities held by the underwriters or related persons do not exceed 1% of the securities being offered; (iv) that is beneficially owned on a pro-rata basis by all equity owners of an investment fund, provided that no participating member manages or otherwise directs investments by the fund and the participating members in the aggregate do not own more than 10% of the equity in the fund; or (v) the exercise or conversion of any security, if all securities remain subject to the lock-up restriction set forth above for the remainder of the time period.

Right of First Refusal

We have also granted H.C. Wainwright & Co., LLC certain rights of first refusal to act as an underwriter or placement agent for a period of twelve months following the closing of this offering.

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Indemnification

Pursuant to the underwriting agreement, we have agreed to indemnify the underwriters against certain liabilities, including liabilities under the Securities Act, or to contribute to payments that the underwriter or such other indemnified parties may be required to make in respect of those liabilities.

Determination of Offering Price

The actual offering price of the securities we are offering will be negotiated between us and the underwriters based on the trading of our shares of common stock prior to the offering, among other things, and may be at a discount to the current market price.

Lock-Up Agreements

We have agreed not to (i) offer, pledge, issue, sell, contract to sell, purchase, contract to purchase, lend or otherwise transfer or dispose of, directly or indirectly, any shares of our common stock or any securities convertible into or exercisable or exchangeable for our common stock; (ii) enter into any swap or other arrangement that transfers, in whole or in part, any of the economic consequences of ownership of shares of common stock; or (iii) file any registration statement with the SEC relating to the offering of any shares of our common stock or any securities convertible into or exercisable or exchangeable for shares of our common stock, without the prior written consent of H.C. Wainwright & Co., LLC for a period of 90 days following the date of this prospectus. This consent may be given at any time without public notice. These restrictions on future issuances are subject to exceptions, including for (i) the issuance of shares of our common stock in this offering and shares of our common stock underlying the pre-funded warrants, common warrants and representative warrants, (ii) the issuance of shares of our common stock upon the exercise of outstanding options or pursuant to certain other rights, (iii) the issuance of shares of our common stock or options to acquire shares of our common stock pursuant to our equity incentive plans, and (iv) the filing of one or more registration statements on Form S-8 with respect to shares of our common stock underlying our equity incentive plans from time to time.

In addition, subject to certain limited circumstances, each of our directors and executive officers, and our principal stockholder, has entered into a lock-up agreement with the underwriters. Under the lock-up agreements, the directors, executive officers and this stockholder may not, directly or indirectly, sell, offer to sell, contract to sell, or grant any option for the sale (including any short sale), grant any security interest in, pledge, hypothecate, hedge, establish an open "put equivalent position" (within the meaning of Rule 16a-1(h) under the Securities Exchange Act of 1934, as amended, or the Exchange Act), or otherwise dispose of, or enter into any transaction which is designed to or could be expected to result in the disposition of, any shares of our common stock or securities convertible into or exchangeable for shares of our common stock, or publicly announce any intention to do any of the foregoing, without the prior written consent of H.C. Wainwright & Co., LLC, for a period of 90 days from the date of this prospectus. This consent may be given at any time without public notice.

Price Stabilization, Short Positions and Penalty Bids

The underwriters may engage in syndicate covering transactions, stabilizing transactions and penalty bids or purchases for the purpose of pegging, fixing or maintaining the price of our shares of common stock:

•: Syndicate covering transactions involve purchases of securities in the open market after the distribution has been completed in order to cover syndicate short positions. Such a naked short position would be closed out by buying securities in the open market. A naked short position is more likely to be created if the underwriter is concerned that there could be downward pressure

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on the price of the securities in the open market after pricing that could adversely affect investors who purchase in the offering.

•: Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specific maximum.
•: Penalty bids permit the underwriter to reclaim a selling concession from a syndicate member when the securities originally sold by the syndicate member are purchased in a stabilizing or syndicate covering transaction to cover syndicate short positions.

These syndicate covering transactions, stabilizing transactions and penalty bids may have the effect of raising or maintaining the market prices of our securities or preventing or retarding a decline in the market prices of our securities. As a result, the price of our shares of common stock may be higher than the price that might otherwise exist in the open market. Neither we nor the underwriter make any representation or prediction as to the effect that the transactions described above may have on the price of our shares of common stock. These transactions may be effected on the Nasdaq Capital Market, in the over-the-counter market or on any other trading market and, if commenced, may be discontinued at any time.

In connection with this offering, the underwriters also may engage in passive market making transactions in our shares of common stock in accordance with Regulation M during a period before the commencement of offers or sales of our shares of common stock in this offering and extending through the completion of the distribution. In general, a passive market maker must display its bid at a price not in excess of the highest independent bid for that security. However, if all independent bids are lowered below the passive market maker's bid that bid must then be lowered when specific purchase limits are exceeded. Passive market making may stabilize the market price of the securities at a level above that which might otherwise prevail in the open market and, if commenced, may be discontinued at any time.

Neither we nor the underwriters make any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the prices of our securities. In addition, neither we nor the underwriters make any representation that the underwriters will engage in these transactions or that any transactions, once commenced, will not be discontinued without notice.

Other Relationships

From time to time, certain of the underwriters and their affiliates have provided, and may provide in the future, various advisory, investment and commercial banking and other services to us in the ordinary course of business, for which they have received and may continue to receive customary fees and commissions.

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MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES

The following is a summary of the material U.S. federal income tax consequences of the acquisition, ownership and disposition of our common stock and the pre-funded warrants and the acquisition, ownership, exercise, expiration or disposition of the common warrants, but does not purport to be a complete analysis of all the potential tax considerations relating thereto. This summary is based upon the provisions of the Internal Revenue Code of 1986, as amended, or the Code, Treasury Regulations promulgated thereunder, administrative rulings and judicial decisions, all as of the date hereof. These authorities may be changed or subject to differing interpretations, possibly with retroactive effect, so as to result in U.S. federal income tax consequences different from those set forth below. We have not sought and will not seek any ruling from the Internal Revenue Service, or the IRS, with respect to the statements made and the conclusions reached in the following summary, and there can be no assurance that the IRS or a court will agree with such statements and conclusions.

This summary also does not address the tax considerations arising under the laws of any U.S. state or local or any non-U.S. jurisdiction, estate or gift tax, the 3.8% Medicare tax on net investment income or any alternative minimum tax consequences. In addition, this discussion does not address tax considerations applicable to a holder's particular circumstances or to a holder that may be subject to special tax rules, including, without limitation:

•: banks, insurance companies or other financial institutions;
•: tax-exempt or government organizations;
•: brokers or dealers in securities or currencies;
•: traders in securities that elect to use a mark-to-market method of accounting for their securities holdings;
•: persons that own, or are deemed to own, more than five percent of our capital stock;
•: certain U.S. expatriates, citizens or former long-term residents of the United States;
•: persons who hold our common stock, pre-funded warrants or common warrants as a position in a hedging transaction, "straddle," "conversion transaction," synthetic security, other integrated investment, or other risk reduction transaction;
•: persons who do not hold our common stock, pre-funded warrants or common warrants as a capital asset within the meaning of Section 1221 of the Code (generally, for investment purposes);
•: persons deemed to sell our common stock, pre-funded warrants or common warrants under the constructive sale provisions of the Code;
•: pension plans;
•: partnerships, or other entities or arrangements treated as partnerships for U.S. federal income tax purposes, or investors in any such entities;
•: persons for whom our stock constitutes "qualified small business stock" within the meaning of Section 1202 of the Code;
•: integral parts or controlled entities of foreign sovereigns;
•: passive foreign investment companies and corporations that accumulate earnings to avoid U.S. federal income tax; or
•: persons that acquire our common stock or pre-funded warrants as compensation for services.

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In addition, if a partnership, including any entity or arrangement classified as a partnership for U.S. federal income tax purposes, holds our common stock, pre-funded warrants or common warrants, the tax treatment of a partner generally will depend on the status of the partner, the activities of the partnership, and certain determinations made at the partner level. Accordingly, partnerships that hold our common stock, pre-funded warrants or common warrants, and partners in such partnerships, should consult their tax advisors regarding the U.S. federal income tax consequences to them of the purchase, ownership, and disposition of our common stock, pre-funded warrants or common warrants.

You are urged to consult your tax advisor with respect to the application of the U.S. federal income tax laws to your particular situation, as well as any tax consequences of the purchase, ownership and disposition of our common stock, pre-funded warrants or common warrants arising under the U.S. federal estate or gift tax rules or under the laws of any U.S. state or local or any non-U.S. or other taxing jurisdiction or under any applicable tax treaty.

Definition of a U.S. Holder

For purposes of this summary, a "U.S. Holder" is any beneficial owner of our common stock, pre-funded warrants or common warrants that is a "U.S. person," and is not a partnership, or an entity treated as a partnership or disregarded from its owner, each for U.S. federal income tax purposes. A U.S. person is any person that, for U.S. federal income tax purposes, is or is treated as any of the following:

•: an individual who is a citizen or resident of the United States;
•: a corporation created or organized under the laws of the United States, any state thereof, or the District of Columbia;
•: an estate, the income of which is subject to U.S. federal income tax regardless of its source; or
•: a trust that (1) is subject to the primary supervision of a U.S. court and the control of one or more U.S. persons (within the meaning of Section 7701(a)(30) of the Code), or (2) has a valid election in effect to be treated as a U.S. person for U.S. federal income tax purposes.

For purposes of this summary, a "Non-U.S. Holder" is any beneficial owner of our common stock, pre-funded warrants or common warrants that is not a U.S. Holder or a partnership, or other entity treated as a partnership or disregarded from its owner, each for U.S. federal income tax purposes.

Treatment of Pre-funded Warrants

Although it is not entirely free from doubt, a pre-funded warrant should be treated as a share of our common stock for U.S. federal income tax purposes and a holder of pre-funded warrants should generally be taxed in the same manner as a holder of common stock, as described below. Accordingly, no gain or loss should be recognized upon the exercise of a pre-funded warrant and, upon exercise, the holding period of a pre-funded warrant should carry over to the share of common stock received. Similarly, the tax basis of the pre-funded warrant should carry over to the share of common stock received upon exercise, increased by the exercise price of $0.10 per share. Each holder should consult his, her or its own tax advisor regarding the risks associated with the acquisition of pre-funded warrants pursuant to this offering (including potential alternative characterizations). The balance of this discussion generally assumes that the characterization described above is respected for U.S. federal income tax purposes.

Allocation of Purchase Price

For U.S. federal income tax purposes, each share of our common stock and the associated common warrant and each pre-funded warrant and the associated common warrant should be treated

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for U.S. federal income tax purposes as an investment unit consisting of one share of common stock and the associated common warrant and one pre-funded warrant and the associated common warrant. Each holder must allocate the purchase price of such unit between each share of common stock or pre-funded warrant, as applicable, and the common warrant based on the relative fair market value of each at the time of issuance. The price allocated to each share of common stock and pre-funded warrant and common warrant generally will be the holder's tax basis in such share or warrant, as the case may be.

Tax Consequences to U.S. Holders

Distributions on Common Stock

As discussed above under "Dividend Policy," we do not currently expect to make distributions on our common stock. In the event that we do make distributions of cash or other property, distributions paid on common stock, other than certain pro rata distributions of common stock, will be treated as a dividend to the extent paid out of our current or accumulated earnings and profits and will be includible in income by the U.S. Holder and taxable as ordinary income when received. If a distribution exceeds our current and accumulated earnings and profits, the excess will be first treated as a tax-free return of the U.S. Holder's investment, up to the U.S. Holder's tax basis in the common stock. Any remaining excess will be treated as a capital gain. Subject to applicable limitations, dividends paid to certain non-corporate U.S. Holders may be eligible for taxation as "qualified dividend income" and therefore may be taxable at rates applicable to long-term capital gains. U.S. Holders should consult their tax advisers regarding the availability of the reduced tax rate on dividends in their particular circumstances. Dividends received by a corporate U.S. Holder will be eligible for the dividends-received deduction if the U.S. Holder meets certain holding period and other applicable requirements.

Constructive Dividends on Common Warrants

If we were to pay a taxable dividend to our shareholders and, in accordance with the anti-dilution provisions of the common warrants, the exercise price of the common warrants were decreased, that decrease would be deemed to be the payment of a taxable dividend to a U.S. Holder of the common warrants to the extent of our current or accumulated earnings and profits, notwithstanding the fact that the U.S. Holder will not receive a cash payment. If the exercise price is adjusted in certain other circumstances (or in certain circumstances, there is a failure to make adjustments), that adjustment may also result in the deemed payment of a taxable dividend to a U.S. Holder. U.S. Holders should consult their tax advisers regarding the proper treatment of any adjustments to the common warrants.

Sale or Other Disposition of Common Stock

For U.S. federal income tax purposes, gain or loss realized on the sale or other disposition of common stock will be capital gain or loss, and will be long-term capital gain or loss if the U.S. Holder held the common stock for more than one year. The amount of the gain or loss will equal the difference between the U.S. Holder's tax basis in the common stock disposed of and the amount realized on the disposition. Long-term capital gains recognized by non-corporate U.S. Holders will be subject to reduced tax rates. The deductibility of capital losses is subject to limitations.

Sale or Other Disposition, Exercise or Expiration of Common Warrants

For U.S. federal income tax purposes, gain or loss realized on the sale or other disposition of a common warrant (other than by exercise) will be capital gain or loss and will be long-term capital gain or loss if the U.S. Holder held the warrant for more than one year at the time of the sale or other disposition. The amount of the gain or loss will equal the difference between the U.S. Holder's tax basis in the common warrant disposed of and the amount realized on the disposition.

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In general, a U.S. Holder will not be required to recognize income, gain or loss upon the exercise of a common warrant by payment of the exercise price, except to the extent of cash paid in lieu of a fractional share. A U.S. Holder's tax basis in a share of common stock received upon exercise will be equal to the sum of (1) the U.S. Holder's tax basis in the common warrant and (2) the exercise price of the common warrant. A U.S. Holder's holding period in the stock received upon exercise will commence on the day or the day after such U.S. Holder exercises the common warrant. No discussion is provided herein regarding the U.S. federal income tax treatment on the exercise of a common warrant on a cashless basis, and U.S. Holders are urged to consult their tax advisors as to the exercise of a common warrant on a cashless basis.

If a common warrant expires without being exercised, a U.S. Holder will recognize a capital loss in an amount equal to such U.S. Holder's tax basis in the common warrant. This loss will be long-term capital loss if, at the time of the expiration, the U.S. Holder's holding period in the common warrant is more than one year. The deductibility of capital losses is subject to limitations.

Tax Consequences to Non-U.S. Holders

Distributions

As discussed in the section titled "Dividend Policy," we do not anticipate paying any dividends on our common stock in the foreseeable future. If we make distributions on our common stock or constructive dividends on our common warrants (as described above under "Constructive Dividends on Common Warrants"), those payments will constitute dividends for U.S. federal income tax purposes to the extent we have current or accumulated earnings and profits, as determined under U.S. federal income tax principles. To the extent those distributions exceed both our current and our accumulated earnings and profits, they will constitute a return of capital and will first reduce a Non-U.S. Holder's basis in our common stock or common warrants, as applicable, but not below zero. Any excess will be treated as capital gain and will be treated as described below under the "—Gain on Sale or Other Disposition of Common Stock or Common Warrants" section. Any such distributions would be subject to the discussions below regarding back-up withholding and Foreign Account Tax Compliance Act, or FATCA.

Subject to the discussion below on effectively connected income, any dividend paid to a Non-U.S. Holder generally will be subject to U.S. withholding tax either at a rate of 30% of the gross amount of the dividend or such lower rate as may be specified by an applicable income tax treaty. To receive a reduced treaty rate, a Non-U.S. Holder must provide us or our agent with an IRS Form W-8BEN (generally including a U.S. taxpayer identification number), IRS Form W-8 BEN-E or another appropriate version of IRS Form W-8 (or a successor form), which must be updated periodically, and which, in each case, must certify qualification for the reduced rate. Non-U.S. Holders should consult their tax advisors regarding their entitlement to benefits under any applicable income tax treaty.

Dividends paid to a Non-U.S. Holder that are effectively connected with the Non-U.S. Holder's conduct of a trade or business within the United States and that are not eligible for relief from U.S. (net basis) income tax under an applicable income tax treaty, generally are exempt from the (gross basis) withholding tax described above. To obtain this exemption from withholding tax, the Non-U.S. Holder must provide the applicable withholding agent with an IRS Form W-8ECI or successor form or other applicable IRS Form W-8 certifying that the dividends are effectively connected with the Non-U.S. Holder's conduct of a trade or business within the United States. Such effectively connected dividends, if not eligible for relief under a tax treaty, would not be subject to a withholding tax, but would be taxed at the same graduated rates applicable to U.S. persons, net of certain deductions and credits and if, in addition, the Non-U.S. Holder is a corporation, may also be subject to a branch profits tax at a rate of 30% (or such lower rate as may be specified by an applicable income tax treaty).

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In the case of any constructive dividend (as described above under "—Tax Consequences to U.S. Holders—Constructive Dividends on Common Warrants"), it is possible that the U.S. federal tax on the constructive dividend would be withheld from shares of common stock, sales proceeds subsequently paid or credited, or other amounts payable or distributable to a Non-U.S. Holder. Non-U.S. Holders who are subject to withholding tax under such circumstances should consult their tax advisers as to whether it can obtain a refund for all or a portion of the withholding tax.

If you are eligible for a reduced rate of withholding tax pursuant to a tax treaty, you may be able to obtain a refund of any excess amounts withheld if you timely file an appropriate claim for refund with the IRS.

Exercise or Expiration of Common Warrants

In general, a Non-U.S. Holder will not be required to recognize income, gain or loss upon the exercise of a common warrant by payment of the exercise price, except to the extent of cash paid in lieu of a fractional share. However, no discussion is provided herein regarding the U.S. federal income tax treatment on the exercise of a common warrant on a cashless basis, and Non-U.S. Holders are urged to consult their tax advisors as to the exercise of a common warrant on a cashless basis.

If a common warrant expires without being exercised, a Non-U.S. Holder that is engaged in a U.S. trade or business to which any income from the common warrant would be effectively connected or who is present in the United States for a period or periods aggregating 183 days or more during the calendar year in which the expiration occurs (and certain other conditions are met) will recognize a capital loss in an amount equal to such Non-U.S. Holder's tax basis in the common warrant.

Gain on Sale or Other Disposition of Common Stock or Common Warrants

Subject to the discussion below regarding backup withholding and FATCA, a Non-U.S. Holder generally will not be required to pay U.S. federal income tax on any gain realized upon the sale or other disposition of our common stock or common warrants unless:

•: the gain is effectively connected with the Non-U.S. Holder's conduct of a trade or business within the United States and not eligible for relief under an applicable income tax treaty, in which case the Non-U.S. Holder will be required to pay tax on the net gain derived from the sale under regular graduated U.S. federal income tax rates, and for a Non-U.S. Holder that is a corporation, such Non-U.S. Holder may be subject to the branch profits tax at a 30% rate (or such lower rate as may be specified by an applicable income tax treaty) on such effectively connected gain, as adjusted for certain items;
•: the Non-U.S. Holder is an individual who is present in the United States for a period or periods aggregating 183 days or more during the calendar year in which the sale or disposition occurs and certain other conditions are met, in which case the Non-U.S. Holder will be required to pay a flat 30% tax on the gain derived from the sale, which tax may be offset by U.S. source capital losses (even though the Non-U.S. Holder is not considered a resident of the United States) (subject to applicable income tax or other treaties); or
•: we are a "U.S. real property holding corporation" for U.S. federal income tax purposes, or a USRPHC, at any time within the shorter of the five-year period preceding the disposition or the Non-U.S. Holder's holding period for our common stock or common warrants. We believe we are not currently and do not anticipate becoming a USRPHC. However, because the determination of whether we are a USRPHC depends on the fair market value of our United States real property interests relative to the fair market value of our other business assets, there can be no assurance that we will not become a USRPHC in the future. Even if we become a USRPHC, however, gain arising from the sale or other taxable disposition by a Non-U.S. Holder

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of our common stock will not be subject to United States federal income tax if (A) in the case of our common stock, (a) shares of our common stock are "regularly traded," as defined by applicable Treasury Regulations, on an established securities market, such as Nasdaq, and (b) the Non-U.S. Holder owns or owned, actually and constructively, 5% or less of the shares of our common stock throughout the five-year period ending on the date of the sale or exchange; and (B) in the case of our common warrants, either (a)(i) shares of our common stock are "regularly traded," as defined by applicable Treasury Regulations, on an established securities market, such as Nasdaq, (ii) our common warrants are not considered regularly traded on an established securities market and (iii) the Non-U.S. Holder does not own, actually or constructively, common warrants with a fair market value greater than the fair market value of 5% of the shares of our common stock, determined as of the date that such Non-U.S. Holder acquired its common warrants, or (b)(i) our common warrants are considered regularly traded on an established securities market, and (ii) the Non-U.S. Holder owns or owned, actually and constructively, 5% or less of our common warrants throughout the five-year period ending on the date of the sale or exchange. Our common warrants are not expected to be regularly traded on an established securities market. If the foregoing exception does not apply, such Non-U.S. Holder's proceeds received on the disposition of shares will generally be subject to withholding at a rate of 15% and such Non-U.S. Holder will generally be taxed on any gain in the same manner as gain that is effectively connected with the conduct of a U.S. trade or business, except that the branch profits tax generally will not apply.

Information Reporting and Backup Withholding

Information returns may be filed with the IRS in connection with distributions on common stock or constructive dividends on common warrants, and the proceeds of a sale or other disposition of common stock. A non-exempt U.S. Holder may be subject to U.S. backup withholding on these payments if it fails to provide its taxpayer identification number to the withholding agent and comply with certification procedures or otherwise establish an exemption from backup withholding.

A Non-U.S. Holder may be subject to U.S. information reporting and backup withholding on these payments unless the Non-U.S. Holder complies with certification procedures to establish that it is not a U.S. person (within the meaning of the Code). The certification requirements generally will be satisfied if the Non-U.S. Holder provides the applicable withholding agent with a statement on the applicable IRS Form (or suitable substitute or successor form), together with all appropriate attachments, signed under penalties of perjury, stating, among other things, that such Non-U.S. Holder is not a U.S. Person. Applicable Treasury Regulations provide alternative methods for satisfying this requirement. In addition, the amount of distributions on common stock or constructive dividends on common warrants paid to a Non-U.S. Holder, and the amount of any U.S. federal tax withheld therefrom, must be reported annually to the IRS and the holder. This information may be made available by the IRS under the provisions of an applicable tax treaty or agreement to the tax authorities of the country in which the Non-U.S. Holder resides.

Payment of the proceeds of the sale or other disposition of common stock or common warrants to or through a non-U.S. office of a U.S. broker or of a non-U.S. broker with certain specified U.S. connections generally will be subject to information reporting requirements, but not backup withholding, unless the Non-U.S. Holder certifies under penalties of perjury that it is not a U.S. person or an exemption otherwise applies. Payments of the proceeds of a sale or other disposition of common stock or common warrants to or through a U.S. office of a broker generally will be subject to information reporting and backup withholding, unless the Non-U.S. Holder certifies under penalties of perjury that it is not a U.S. person or otherwise establishes an exemption.

Backup withholding is not an additional tax. The amount of any backup withholding from a payment generally will be allowed as a credit against the holder's U.S. federal income tax liability and

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may entitle the holder to a refund, provided that the required information is timely furnished to the IRS.

Foreign Accounts

The Code generally imposes a U.S. federal withholding tax of 30% on dividends and, subject to the discussion below regarding proposed regulations recently issued by the U.S. Treasury Department, the gross proceeds of a disposition of our securities paid to a "foreign financial institution" (as specifically defined for this purpose), unless such institution enters into an agreement with the U.S. government to, among other things, withhold on certain payments and to collect and provide to the U.S. tax authorities substantial information regarding U.S. account holders of such institution (which includes certain equity and debt holders of such institution, as well as certain account holders that are foreign entities with U.S. owners) or otherwise qualifies for an exemption from these rules. A U.S. federal withholding tax of 30% also applies to dividends and, subject to the discussion below regarding proposed regulations recently issued by the U.S. Treasury Department, will apply to the gross proceeds of a disposition of our securities paid to a non-financial foreign entity (as defined in the Code), unless such entity provides the withholding agent with either a certification that it does not have any substantial direct or indirect.

Under certain circumstances, a non-U.S. holder might be eligible for refunds or credits of such taxes. An intergovernmental agreement between the United States and an applicable foreign country may modify the requirements described in this paragraph.

The U.S. Treasury Department recently released proposed regulations which, if finalized in their present form, would eliminate the federal withholding tax of 30% applicable to the gross proceeds of a sale or other disposition of our common stock. In its preamble to such proposed regulations, the U.S. Treasury Department stated that taxpayers may generally rely on the proposed regulations until final regulations are issued. Prospective investors should consult their own tax advisors regarding the possible impact of these rules on their investment in our common stock, and the possible impact of these rules and the proposed regulations on the entities through which they hold our common stock, including, without limitation, the process and deadlines for meeting the applicable requirements to prevent the imposition of this 30% withholding tax.

EACH PROSPECTIVE INVESTOR SHOULD CONSULT ITS TAX ADVISOR REGARDING THE PARTICULAR U.S. FEDERAL, STATE AND LOCAL AND NON-U.S. TAX CONSEQUENCES OF PURCHASING, HOLDING AND DISPOSING OF OUR SECURITIES, INCLUDING THE CONSEQUENCES OF ANY PROPOSED CHANGE IN APPLICABLE LAWS. IN ADDITION, SIGNIFICANT CHANGES IN U.S. FEDERAL TAX LAWS WERE RECENTLY ENACTED. PROSPECTIVE INVESTORS SHOULD ALSO CONSULT WITH THEIR TAX ADVISORS WITH RESPECT TO SUCH CHANGES IN U.S. TAX LAW AS WELL AS POTENTIAL CONFORMING CHANGES IN STATE TAX LAWS.

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LEGAL MATTERS

Cooley LLP of Palo Alto, California will pass upon the validity of the securities offered hereby. The underwriters are being represented by McDermott Will & Emery LLP in connection with the offering.

EXPERTS

The consolidated financial statements of Vaxart, Inc. as of December 31, 2018 and 2017, and for each of the years in the two year period ended December 31, 2018, have been incorporated by reference herein in reliance upon the report of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing. The audit report covering the December 31, 2018 consolidated financial statements contains an explanatory paragraph that states that the Company has experienced losses and negative cash flows from operations since its inception, has an accumulated deficit, and has debt obligations which raise substantial doubt about its ability to continue as a going concern. The consolidated financial statements do not include any adjustments that might result from the outcome of that uncertainty.

On February 13, 2018, privately-held Vaxart, Inc., or Private Vaxart, and Aviragen Therapeutics, Inc., or Aviragen, completed a business combination in accordance with the terms an agreement and plan of merger and reorganization, dated October 27, 2017, by and among Aviragen, Agora Merger Sub, Inc., or Merger Sub, and Private Vaxart, pursuant to which Merger Sub merged with and into Private Vaxart, with Private Vaxart surviving as a wholly-owned subsidiary of Aviragen, or the Merger. Aviragen changed its name at the closing of the Merger to Vaxart, Inc., or the Combined Company, and Private Vaxart changed its name to Vaxart Biosciences, Inc. For accounting purposes, Aviragen was deemed to be the acquired entity in the Merger, and the financial statements of Private Vaxart became the historical financial statements of the Combined Company following the Merger.

In connection with the closing of the Merger on February 13, 2018, the board of directors of Vaxart, Inc. dismissed Ernst & Young LLP as its independent registered public accounting firm, effective immediately. The reports of Ernst & Young LLP on Aviragen Therapeutics, Inc.'s consolidated financial statements for the fiscal years ended June 30, 2017 and 2016 did not contain an adverse opinion or disclaimer of opinion, nor were they qualified or modified as to uncertainty, audit scope, or accounting principles. During the fiscal years ended June 30, 2017 and 2016, and the subsequent interim period through February 13, 2018 there were no: (1) disagreements (as defined in Item 304(a)(1)(iv) of Regulation S-K and the related instructions) with Ernst & Young LLP on any matter of accounting principles or practices, financial statement disclosure, or auditing scope or procedures, which disagreement if not resolved to the satisfaction of Ernst & Young LLP would have caused Ernst & Young LLP to make reference thereto in its reports on the consolidated financial statements for such years, or (2) reportable events (as described in Item 304(a)(1)(v) of Regulation S-K).

On February 13, 2018, the board of directors of Vaxart, Inc., in connection with the Merger and the dismissal of Ernst & Young LLP, approved the engagement of KPMG LLP as the Combined Company's independent registered public accounting firm for the year ending December 31, 2017.

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WHERE YOU CAN FIND MORE INFORMATION

We have filed with the SEC a registration statement on Form S-1 under the Securities Act with respect to the shares of common stock and pre-funded warrants. This prospectus, which constitutes a part of the registration statement, does not contain all of the information set forth in the registration statement or the exhibits filed with the registration statement. For further information about us and the common stock and pre-funded warrants offered hereby, we refer you to the registration statement and the exhibits filed with the registration statement. Statements contained in this prospectus regarding the contents of any contract or any other document that is filed as an exhibit to the registration statement are not necessarily complete, and each such statement is qualified in all respects by reference to the full text of such contract or other document filed as an exhibit to the registration statement.

We are subject to the information and reporting requirements of the Exchange Act and, in accordance with this law, are required to file periodic reports, proxy statements and other information with the SEC. You can read our SEC filings, including the registration statement, over the internet at the SEC's website at www.sec.gov .

We make available free of charge, on or through the investor relations section of our website, annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. The information found on our website, www.vaxart.com , other than as specifically incorporated by reference in this prospectus, is not part of this prospectus.

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INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to "incorporate by reference" information from other documents that we file with it, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus. Information in this prospectus supersedes information incorporated by reference that we filed with the SEC prior to the date of this prospectus, while information that we file later with the SEC will automatically update and supersede the information in this prospectus. We incorporate by reference into this prospectus and the registration statement of which this prospectus is a part the information or documents listed below that we have filed with the SEC (Commission File No. 001-35285):

•: our Annual Report on Form 10-K for the year ended December 31, 2018, filed with the SEC on February 6, 2019;
•: our definitive proxy statement relating to our 2019 annual meeting of stockholders, filed with the SEC on March 11, 2019;
•: our Current Reports on Form 8-K filed with the SEC on January 18, 2019, March 19, 2019, March 20, 2019, and March 27, 2019; and
•: the description of our common stock contained in our Registration Statement on Form 10, filed with the SEC on May 4, 1970, as amended by our Current Report on Form 8-K (File No. 000-04829) filed with the SEC on August 15, 2003.

We also incorporate by reference any future filings (other than current reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits filed on such form that are related to such items unless such Form 8-K expressly provides to the contrary) made with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, until the termination of the offering of the shares of our common stock made by this prospectus and will become a part of this prospectus from the date that such documents are filed with the SEC. Information in such future filings updates and supplements the information provided in this prospectus. Any statements in any such future filings will automatically be deemed to modify and supersede any information in any document we previously filed with the SEC that is incorporated or deemed to be incorporated herein by reference to the extent that statements in the later filed document modify or replace such earlier statements.

You can request a copy of these filings, at no cost, by writing or telephoning us at the following address or telephone number:

Vaxart, Inc.
290 Utah Ave
Suite 200
South San Francisco, California 94080
Attn: Secretary
(650) 550-3500

Copies of these filings are also available through the "Investor" section of our website at www.vaxart.com . For other ways to obtain a copy of these filings, please refer to "Where You Can Find More Information" above.

Any information in any of the foregoing documents will automatically be deemed to be modified or superseded to the extent that information in this prospectus modifies or replaces such information.

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5,300,000 Shares of Common Stock

Pre-Funded Warrants to Purchase Shares of Common Stock

Common Warrants to Purchase 5,300,000 Shares of Common Stock

Prospectus

Sole Book-Running Manager

H.C. Wainwright & Co.

Manager

CIM Securities, LLC

, 2019

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PART II—INFORMATION NOT REQUIRED IN PROSPECTUS

ITEM 13. OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION

The following table sets forth an estimate of the fees and expenses, other than underwriting discounts and commissions payable by us in connection with the issuance and distribution of the securities being registered. All the amounts shown are estimates, except for the SEC registration fee and the FINRA filing fee.

	Amount

SEC registration fee	$	4,151
FINRA filing fee		5,637
Accounting fees and expenses		100,000
Legal fees and expenses		250,000
Transfer agent and registrar fees		15,000
Printing fees		100,000
Miscellaneous expenses		125,212

Total	$	600,000

ITEM 14. INDEMNIFICATION OF DIRECTORS AND OFFICERS

Section 145 of the Delaware General Corporation Law authorizes a court to award, or a corporation's board of directors to grant, indemnity to directors and officers in terms sufficiently broad to permit such indemnification under certain circumstances for liabilities, including reimbursement for expenses incurred, arising under the Securities Act of 1933, as amended, or the Securities Act.

Our amended and restated certificate of incorporation provide for indemnification of our directors, officers, employees and other agents to the maximum extent permitted by the Delaware General Corporation Law, and our amended and restated bylaws require us to indemnify our directors, officers, employees, and other agents to the maximum extent permitted by the Delaware General Corporation Law. However, Delaware law prohibits the Registrant's certificate of incorporation from limiting the liability of the Registrant's directors for the following:

•: any breach of the director's duty of loyalty to us or to our stockholders;
•: acts or omissions not in good faith or that involve intentional misconduct or a knowing violation of law;
•: unlawful payment of dividends or unlawful stock repurchases or redemptions; and
•: any transaction from which the director derived an improper personal benefit.

We have entered and expect to continue to enter into agreements to indemnify our directors and executive officers. With certain exceptions, these agreements provide for indemnification for related expenses including, among other things, attorneys' fees, judgments, fines and settlement amounts incurred by any of these individuals in any action or proceeding. At present, there is no pending litigation or proceeding involving any of our directors, officers or employees for which indemnification is sought and we are not aware of any threatened litigation that may result in claims for indemnification.

We maintain insurance policies that indemnify our directors and officers against various liabilities arising under the Securities Act and the Exchange Act that might be incurred by any director or officer in his capacity as such.

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The Underwriting Agreement filed as Exhibit 1.1 to this Registration Statement provides for indemnification by the underwriters of us and our directors and officers for certain liabilities under the Securities Act, or otherwise.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted for directors, executive officers or persons controlling us, we have been informed that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

ITEM 15. RECENT SALES OF UNREGISTERED SECURITIES

None.

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ITEM 16. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

(a): Exhibits.

				Incorporated by Reference

Exhibit Number				Schedule/ Form	File Number	Exhibit	File Date
	1.1		Underwriting Agreement.
	2.1		Agreement and Plan of Merger and Reorganization, dated October 27, 2017, by and among Aviragen Therapeutics, Inc., Vaxart, Inc. and Agora Merger Sub, Inc.	8-K	001-35285	2.1	October 30, 2017
	2.2		Amendment No. 1, dated as of February 7, 2018, to the Agreement and Plan of Merger and Reorganization, dated October 27, 2017, by and among Aviragen Therapeutics, Inc., Vaxart, Inc. and Agora Merger Sub, Inc.	8-K	001-35285	2.1	February 7, 2018
	3.1		Restated Certificate of Incorporation of Aviragen Therapeutics, Inc.	10-K	001-35285	3.1	September 13, 2016
	3.2		Certificate of Amendment to Restated Certificate of Incorporation of Aviragen Therapeutics, Inc.	8-K	001-35285	3.1	February 20, 2018
	3.3		Certificate of Amendment to Restated Certificate of Incorporation of Vaxart, Inc.	8-K	001-35285	3.2	February 20, 2018
	3.4		Restated By-laws of Aviragen Therapeutics, Inc.	10-K	001-35285	3.2	September 13, 2016
	4.1		Reference is made to Exhibits 3.1 to 3.3 .
	4.2		Specimen Common Stock Certificate.	S-3	333-228910	4.2	December 20, 2018
	4.3		Form of Pre-Funded Warrant.	S-1	333-229536	10.25	February 6, 2019
	4.4		Form of Common Warrant.
	4.5		Form of Representative Warrant.
	5.1		Opinion of Cooley LLP.
	10.1	+	Collaboration and License Agreement dated September 29, 2003, between Biota Holdings Limited and Sankyo Co., Ltd.	10-Q	001-35285	10.5	May 10, 2013
	10.2	+	Amendment #1 to Collaboration and License Agreement dated June 30, 2005, between Biota Holdings Limited, Biota Scientific Management Pty. Ltd. and Sankyo Company, Ltd.	10-Q	001-35285	10.6	May 10, 2013

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				Incorporated by Reference

Exhibit Number				Schedule/ Form	File Number	Exhibit	File Date
	10.3		Amendment #2 to Collaboration and License Agreement, dated March 27, 2009, between Biota Holdings Limited, Biota Scientific Management Pty. Ltd. and Daiichi Sankyo Company, Limited	10-Q	001-35285	10.7	May 10, 2013
	10.4	+	Commercialization Agreement dated March 27, 2009, between Biota Holdings Limited, Biota Scientific Management Pty. Ltd and Daiichi Sankyo Company, Ltd.	10-Q	001-35285	10.8	May 10, 2013
	10.5	+	Contract dated March 31, 2011, between Biota Scientific Management Pty. Ltd. and Office of Biomedical Advanced Research and Development Authority within the Office of the Assistant Secretary for preparedness and Response at the U.S. Department of Health and Human Services	10-Q	001-35285	10.9	May 10, 2013
	10.6		Research and License Agreement dated February 21, 1990, by and among Biota Scientific Management Pty. Ltd., Biota Holdings Limited, Glaxo Australia Pty. Ltd. and Glaxo Group Limited	10-K	001-35285	10.6	September 27, 2013
	10.7	#	2007 Omnibus Equity and Incentive Plan (included as Appendix A to the proxy statement)	DEF 14A	000-04829	—	April 12, 2007
	10.8	#	Form of Employee Stock Option Agreement under the 2007 Omnibus Equity and Incentive Plan	8-K	001-35285	10.1	December 10, 2013
	10.9	+	Royalty Interest Acquisition Agreement by and between Aviragen Therapeutics, Inc., Biota Holdings Pty Ltd, Biota Scientific Management Pty. Ltd. and HealthCare Royalty Partners III, L.P. dated April 22, 2016	8-K	001-35285	10.1	April 26, 2016
	10.10		Protective Rights Agreement between Aviragen Therapeutics, Inc. and HealthCare Royalty Partners III, L.P. dated April 22, 2016	8-K	001-35285	10.2	April 26, 2016
	10.11	#	Form of Employee Stock Option Agreement under the 2016 Equity Incentive Plan	10-Q	001-35285	10.1	May 8, 2017

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				Incorporated by Reference

Exhibit Number				Schedule/ Form	File Number	Exhibit	File Date
	10.12	#	2016 Equity Incentive Plan (included as Appendix A to the proxy statement)	DEF 14A	001-35285	—	September 27, 2016
	10.13	#	Director Stock Option Agreement	S-4	333-222009	10.22	December 12, 2017
	10.14		Form of Indemnification Agreement by and between Vaxart, Inc. and its Directors and Executive Officers.	8-K	001-35285	10.3	February 20, 2018
	10.15	#	Vaxart, Inc. Amended and Restated 2007 Equity Incentive Plan, Stock Option Agreement, form of Notice of Stock Option Grant, form of Additional Terms and Conditions to Option and Stock Option Exercise Agreement	S-4/A	333-222009	10.24	December 29, 2017
	10.16	#	Offer Letter, dated May 25, 2011, and Amendment to Offer Letter and Option Grant Agreement, dated October 1, 2011, by and between Vaxart, Inc. and Wouter W. Latour, M.D.	S-4/A	333-222009	10.25	December 29, 2017
	10.17		Industrial Lease dated October 28, 2013, by and between Vaxart, Inc. and Oyster Point LLC	S-4/A	333-222009	10.26	December 29, 2017
	10.18		Lease Agreement dated April 17, 2015, by and between Vaxart, Inc. and CRP Edgewater, LLC	S-4/A	333-222009	10.27	December 29, 2017
	10.19		Loan and Security Agreement dated December 22, 2016, by and between Vaxart, Inc. and Oxford Finance LLC	S-4/A	333-222009	10.28	December 29, 2017
	10.20		Second Amendment to the Loan Agreement, dated February 13, 2018, between Vaxart, Inc. and Oxford Finance LLC.	8-K	001-35285	10.1	February 20, 2018
	10.21	#	Severance Benefit Plan and Form of Severance Benefit Plan Participation Notice.	8-K	001-35285	10.1	June 6, 2018
	10.22		Settlement Agreement by and among Vaxart, Inc., Digirad Corporation, East Hill Management Company, LLC, and Aviragen Therapeutics, Inc.	8-K	001-35285	10.1	February 9, 2018
	10.23		Form of Sales Agreement dated December 19, 2018 by and between Vaxart, Inc. and B. Riley FBR, Inc.	S-3	333-228910	1.2	December 20, 2018

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			Incorporated by Reference

Exhibit Number			Schedule/ Form	File Number	Exhibit	File Date
	10.24	Amended and Restated Warrant issued to Oxford Finance LLC, dated February 13, 2018.	8-K	001-35285	10.2	February 20, 2018
	10.25	Form of Securities Purchase Agreement dated as of March 19, 2019, by and among Vaxart, Inc. and the Purchasers named therein.	8-K	001-35285	10.1	March 20, 2019
	10.26	Form of Placement Warrant.	8-K	001-35285	10.3	March 20, 2019
	16.1	Letter dated February 16, 2018 from Ernst & Young LLP to the Securities and Exchange Commission.	8-K	001-35285	16.1	February 20, 2018
	21.1	List of Subsidiaries.	10-K	001-35285	21.1	February 6, 2019
	23.1	Consent of KPMG LLP, Independent Registered Public Accounting Firm.
	23.2	Consent of Cooley LLP is contained in Exhibit 5.1 to this Registration Statement.
	24.1	Power of Attorney (see the signature page to the original filing of this registration statement on Form S-1).	S-1	333-229536		February 6, 2019

#: Management contract or compensation plan or arrangement.
+: Confidential portions of this exhibit have been omitted and filed separately with the Commission pursuant to confidential treatment granted under Rule 24b-2 promulgated under the Exchange Act

(b): Financial Statement Schedules.

Financial statement schedules have been omitted, as the information required to be set forth therein is included in the Consolidated Financial Statements or Notes thereto appearing in the prospectus made part of this registration statement.

ITEM 17. UNDERTAKINGS

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

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The undersigned Registrant hereby undertakes:

(1): To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20 percent change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement;

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

(2): That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.
(3): To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.
(4): That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, the undersigned Registrant undertakes that in a primary offering of securities of the undersigned Registrant pursuant to this registration statement, regardless of the method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned Registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned Registrant relating to the offering required to be filed pursuant to Rule 424 (§230.424 of this chapter);

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned Registrant or used or referred to by the undersigned Registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned Registrant or its securities provided by or on behalf of the undersigned Registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned Registrant to the purchaser.

(5): For purposes of determining any liability under the Securities Act, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by the Registrant pursuant to Rule 424(b)(1) or (4) or 497(h) under the Securities Act shall be deemed to be part of this registration statement as of the time it was declared effective.
(6): For the purpose of determining any liability under the Securities Act, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the Registrant has duly caused this Amendment No. 2 to Registration Statement to be signed on its behalf by the undersigned, in the City of South San Francisco, State of California, on April 8, 2019.


		VAXART, INC.
		By:		/s/ WOUTER W. LATOUR, M.D. Wouter W. Latour, M.D. President and Chief Executive Officer

Pursuant to the requirements of the Securities Act of 1933, this Amendment No. 2 to Registration Statement has been signed below by the following persons in the capacities and on the dates indicated.

Signatures		Title	Date


/s/ WOUTER W. LATOUR, M.D. Wouter W. Latour, M.D.		President, Chief Executive Officer and Director (Principal Executive Officer and Principal Financial Officer)	April 8, 2019
/s/ MARGARET A. ECHERD Margaret A. Echerd		Vice President, Corporate Controller (Principal Accounting Officer)	April 8, 2019
* Richard J. Markham		Chairman of the Board	April 8, 2019
* Michael J. Finney, Ph.D.		Director	April 8, 2019
* Anne M. VanLent		Director	April 8, 2019
* Geoffrey F. Cox, Ph.D.		Director	April 8, 2019
* John P. Richard		Director	April 8, 2019
By:	/s/ WOUTER W. LATOUR, M.D. Wouter W. Latour, M.D. Attorney-in-Fact

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Exhibit 1.1

Vaxart, Inc.

[ · ] Shares of Common Stock

Pre-Funded Warrants to Purchase [ · ] Shares of Common Stock

Common Warrants to Purchase [ · ] Shares of Common Stock

Underwriting Agreement

April [ · ], 2019

H.C. Wainwright & Co., LLC

As Representative of the several
Underwriters listed in Schedule A hereto

430 Park Avenue, 4 th Floor

New York, NY 10022

Ladies and Gentlemen:

Vaxart, Inc., Inc., a Delaware corporation (the “ Company ”), proposes to issue and sell to the several underwriters named in Schedule A (the “ Underwriters ”) (i) an aggregate of (a) [ · ] shares of common stock (the “ Firm Shares ”), par value $0.10 per share, of the Company (the “ Common Stock ”), (b) [ · ] pre-funded warrants to purchase [ · ] shares of Common Stock at an exercise price of $0.10 per share (the “ Pre-Funded Warrants ”) and (c) warrants to purchase [ · ] shares of Common Stock at an exercise price of $[ · ] per share (the “ Common Warrants ” and, collectively with the Pre-Funded Warrants and the Firm Shares, the “ Firm Securities ”). The amount and form of the Firm Securities to be purchased by the Underwriters is set forth opposite its name on Schedule A hereto. The Company also proposes to sell to the Underwriters, at the option of the Underwriters, up to (i) an additional [ · ] shares of Common Stock (the “ Option Shares ”), (ii) [ · ] Common Warrants (the “ Option Warrants ”), and, to the Representative (as defined below), warrants in an amount set forth in Section 2(g) below (the “ Representative Warrants ” and, together with the Option Shares and the Option Warrants, the “ Option Securities ”). The Firm Shares and the Option Shares are collectively referred to herein as the “ Shares ”; the Pre-Funded Warrants, the Common Warrants, the Option Warrants and the Representative Warrants are collectively referred to herein as the “ Warrants ”; the shares of Common Stock issuable upon exercise of the Pre-Funded Warrants, the Common Warrants, the Option Warrants and the Representative Warrants are collectively referred to herein as the “ Warrant Shares ”; and the Firm Securities, the Option Securities and the Warrant Shares are collectively referred to herein as the “ Securities .” The terms of the Pre-Funded Warrants are set forth in the form of Pre-Funded Warrant filed as an exhibit to the Initial Registration Statement (as defined below), the terms of the Common Warrants are set forth in the form of Common Warrant filed as an exhibit to the

Initial Registration Statement, and the terms of the Representative Warrants (as defined in Section 2(g) are set forth in the form of Representative Warrant filed as an exhibit to the Initial Registration Statement.

H.C. Wainwright & Co., LLC (“ Wainwright ”) has agreed to act as representative of the several Underwriters (in such capacity, the “ Representative ”) in connection with the offering and sale of the Securities. To the extent there are no additional underwriters listed on Schedule A , the term “ Representative ” as used herein shall mean you, as Underwriter, and the term “Underwriters” shall mean either the singular or the plural, as the context requires.

The Company hereby confirms its agreements with the Underwriters as follows:

1. Representations and Warranties of the Company . The Company represents and warrants to each Underwriter as of the date of this Agreement, the Applicable Time and the Closing Date (as hereinafter defined) and each Option Closing Date (as hereinafter defined) as follows:

(a) A registration statement of the Company on Form S-1 (File No. 333-229536) in respect of the Securities and one or more pre-effective amendments thereto (collectively, the “ Initial Registration Statement ”) have been filed with the Securities and Exchange Commission (the “ Commission ”); the Initial Registration Statement and any post-effective amendment thereto, each in the form heretofore delivered to you, have been declared effective by the Commission in such form; other than a registration statement, if any, increasing the size of the offering (a “ Rule 462(b) Registration Statement ”), filed pursuant to Rule 462(b) under the Securities Act of 1933, as amended (the “ Securities Act ”), which became effective upon filing, no other document with respect to the Initial Registration Statement has heretofore been filed with the Commission; no stop order suspending the effectiveness of the Initial Registration Statement, any post-effective amendment thereto or the Rule 462(b) Registration Statement, if any, has been issued, no proceeding for that purpose has been initiated or, to the Company’s knowledge, threatened by the Commission and any request on the part of the Commission for additional information from the Company has been satisfied in all material respects; any preliminary prospectus included in the Initial Registration Statement, as originally filed or as part of any amendment thereto, or filed with the Commission pursuant to Rule 424(a) of the rules and regulations of the Commission under the Securities Act is hereinafter called a “ Preliminary Prospectus ”; the various parts of the Initial Registration Statement and the Rule 462(b) Registration Statement, if any, including (i) all documents incorporated by reference therein, (ii) all schedules and exhibits thereto and (iii) the information contained in the form of final prospectus filed with the Commission pursuant to Rule 424(b) under the Securities Act and deemed by virtue of Rule 430A under the Securities Act to be part of the Initial Registration Statement at the time it was declared effective or such part of the Rule 462(b) Registration Statement, if any, became or hereafter becomes effective, each as amended at the time such part of the Initial Registration Statement became effective, are hereinafter collectively called the “ Registration Statement ”; the Preliminary Prospectus relating to the Securities that was included in the Registration Statement immediately prior to the Applicable Time (as defined in Section 1(c) hereof) is hereinafter called the “ Pricing Prospectus ”; such final prospectus, in the form first filed pursuant to Rule 424(b) under the Securities Act, is hereinafter called the “ Prospectus ”; and any “free writing prospectus” as defined in Rule 433 under the Securities Act relating to the Securities is hereinafter called a “ free writing prospectus ”; any reference to “amend”, “amendment” or “supplement” with respect to the Registration Statement, the Rule 462 Registration Statement, any Preliminary Prospectus, the Pricing

Prospectus, the Initial Registration Statement, the Pricing Disclosure Package (as defined below) or the Prospectus shall be deemed to refer to and include any documents filed after the effective date of the Initial Registration Statement, the Registration Statement or the Rule 462 Registration Statement or the date of such Preliminary Prospectus, the Pricing Prospectus, the Pricing Disclosure Package or the Prospectus, as the case may be under the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission thereunder (collectively, the “ Exchange Act ”) that are deemed to be incorporated by reference therein; all references in this Agreement to financial statements and schedules and other information which are “contained,” “included” or “stated” in, or “part of” the Registration Statement, the Preliminary Prospectus, the Pricing Prospectus, the Pricing Disclosure Package or the Prospectus, and all other references of like import, shall be deemed to mean and include all such financial statements and schedules and other information which is or is deemed to be incorporated by reference in the Registration Statement, the Preliminary Prospectus, the Pricing Prospectus, the Pricing Disclosure Package or the Prospectus, as the case may be; all references in this Agreement to (i) the Registration Statement, the Preliminary Prospectus, the Pricing Prospectus or the Prospectus, any amendments or supplements to any of the foregoing, or any free writing prospectus, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (“ EDGAR ”) and (ii) the Prospectus shall be deemed to include any “electronic Prospectus” provided for use in connection with the offering of the Securities as contemplated by Section 3(n) of this Agreement.

(b) At the respective times the Initial Registration Statement, any Rule 462(b) Registration Statement and any post-effective amendments thereto became effective and at the Closing Date (and, if any Option Securities are purchased, at each Option Closing Date), the Initial Registration Statement, any Rule 462(b) Registration Statement and any amendments and supplements thereto complied and will comply in all material respects with the requirements of the Securities Act and the rules and regulations of the Commission thereunder (the “ Rules and Regulations ”).

(c) (1) Neither the Registration Statement nor any amendment thereto, at its effective time, as of the Applicable Time, at the Closing Date or at any Option Closing Date (if any), contained, contains or will contain an untrue statement of a material fact or omitted, omits or will omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading; (2) the Pricing Disclosure Package, as of the Applicable Time, did not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; and (3) as of the date of the Prospectus and any amendments or supplements thereto and at the Closing Date (and, if any Option Securities are purchased, at each Option Closing Date (as defined herein)), neither the Prospectus nor any amendment or supplement thereto included or will include an untrue statement of a material fact or omitted or will omit to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading; provided that the representations and warranties in clauses (1), (2) and (3) above shall not apply to statements in or omissions from the Registration Statement, Pricing Disclosure Package or the Prospectus made in reliance upon and in strict conformity with information furnished to the Company in writing by the Underwriter expressly for use in the Registration Statement, Pricing Disclosure Package or the Prospectus or any amendment or supplement thereto, it being understood and agreed that the only such information provided by the Underwriter is that

described as such in Section 9(b) hereof. No order preventing or suspending the use of any Preliminary Prospectus, the Pricing Prospectus, the Prospectus or any free writing prospectus has been issued by the Commission;

As used herein, “ Applicable Time ” is [ :00 a.m./p.m.] (Eastern time) on April [•], 2019. As used herein, “ free writing prospectus ” has the meaning set forth in Rule 405 under the Securities Act, and “ Pricing Disclosure Package ” means the Preliminary Prospectus, as amended or supplemented immediately prior to the Applicable Time, together with the free writing prospectuses, if any, identified on Schedule B hereto and the pricing information set forth on Schedule C hereto. As used herein, “ Road Show ” means a “road show” (as defined in Rule 433 under the Securities Act) relating to the offering of the Securities contemplated hereby that is a “written communication” (as defined in Rule 405 under the Securities Act).

(d) Each Preliminary Prospectus, Pricing Prospectus, and the Prospectus filed as part of the Initial Registration Statement as originally filed or as part of any amendment thereto, or filed pursuant to Rule 424 under the Securities Act, complied when so filed in all material respects with the requirements of the Securities Act and the Rules and Regulations and each Preliminary Prospectus, Pricing Prospectus, and the Prospectus delivered to the Underwriter for use in connection with this offering was identical to the electronically transmitted copies thereof filed with the Commission pursuant to EDGAR, except to the extent permitted by Regulation S-T. The documents incorporated or deemed to be incorporated by reference in the Registration Statement, the Pricing Prospectus and the Prospectus, at the time they were or hereafter are filed with the Commission, or became effective under the Exchange Act, as the case may be, complied and will comply in all material respects with the requirements of the Exchange Act. There are no contracts or other documents required to be described in the Preliminary Prospectus, Pricing Prospectus, or the Prospectus or to be filed as an exhibit to the Registration Statement which have not been described or filed as required.

(e) Free Writing Prospectuses; Road Show . The Company is not, and at the time of filing the Initial Registration Statement, was not an “ineligible issuer,” as defined under Rule 405 under the Securities Act. Each free writing prospectus that the Company is required to file pursuant to Rule 433(d) under the Securities Act has been, or will be, filed with the Commission in accordance with the requirements of the Securities Act. Each free writing prospectus that the Company has filed, or is required to file, pursuant to Rule 433(d) under the Securities Act or that was prepared by or on behalf of or used or referred to by the Company complies or will comply in all material respects with the requirements of Rule 433 under the Securities Act, including timely filing with the Commission or retention where required and legending, and each such free writing prospectus, as of its issue date and at all subsequent times through the completion of the public offer and sale of the Securities did not, does not and will not include any information that conflicted, conflicts or will conflict with the information contained in the Registration Statement, the Prospectus or any preliminary prospectus and not superseded or modified. Except for the free writing prospectuses, if any, identified in Schedule B , and electronic road shows, if any, furnished to you before first use, the Company has not prepared, used or referred to, and will not, without your prior written consent, prepare, use or refer to, any free writing prospectus. Each Road Show, when considered together with the Pricing Disclosure Package, does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(f) Distribution of Offering Material By the Company . Prior to the later of (i) the expiration or termination of the option granted to the several Underwriters in Section 2, and (ii) the completion of the Underwriters’ distribution, the Company has not distributed and will not distribute any offering material in connection with the offering and sale of the Securities other than the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(g) Financial Information . The consolidated financial statements of the Company included or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus, if any, together with the related notes and schedules, present fairly, in all material respects, the consolidated financial position of the Company and the Subsidiaries (as defined below) as of the dates indicated and the consolidated results of operations, cash flows and changes in stockholders’ equity of the Company for the periods specified and have been prepared in compliance with the requirements of the Securities Act and Exchange Act, and in conformity with U.S. generally accepted accounting principles (“ GAAP ”) applied on a consistent basis during the periods involved; there are no financial statements (historical or pro forma) that are required to be included or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus that are not included or incorporated by reference as required; the Company and the Subsidiaries (as defined below) do not have any material liabilities or obligations, direct or contingent (including any off-balance sheet obligations), not described in the Registration Statement (excluding the exhibits thereto), the Pricing Disclosure Package and the Prospectus; and all disclosures contained or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus and any free writing prospectuses, if any, regarding “non-GAAP financial measures” (as such term is defined by the rules and regulations of the Commission) comply with Regulation G of the Exchange Act and Item 10 of Regulation S-K under the Securities Act, to the extent applicable. The consolidated financial data set forth in each of the Registration Statement, the Pricing Disclosure Package and the Prospectus fairly present the information set forth therein on a basis consistent with that of the consolidated audited financial statements incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus. The interactive data in eXtensible Business Reporting Language incorporated by reference in the Registration Statement and the Prospectus fairly presents the information called for in all material respects and has been prepared in accordance with the Commission’s rules and guidelines applicable thereto.

(h) Conformity with EDGAR Filing . Each Preliminary Prospectus and Prospectus delivered to the Underwriter for use in connection with the sale of the Securities pursuant to this Agreement was and will be identical to the versions of each Preliminary Prospectus and Prospectus transmitted to the Commission for filing via EDGAR, except to the extent permitted by Regulation S-T.

(i) Organization . The Company and each of its Subsidiaries are duly organized, validly existing as a corporation and in good standing under the laws of their respective jurisdictions of organization. The Company and each of its Subsidiaries are duly licensed or qualified as a foreign corporation for transaction of business and in good standing under the laws of each other jurisdiction in which their respective ownership or lease of property or the conduct of their respective businesses requires such license or qualification, and have all corporate power and authority necessary to own or hold their respective properties and to conduct their respective businesses as described in the Registration Statement, the Pricing Disclosure Package and the

Prospectus, and as currently carried on, except where the failure to be so qualified or in good standing or have such power or authority would not, individually or in the aggregate, have a material adverse effect on the assets, business, operations, earnings, properties, condition (financial or otherwise), prospects, stockholders’ equity or results of operations of the Company and the Subsidiaries taken as a whole, or prevent or materially interfere with consummation of the transactions contemplated hereby (a “ Material Adverse Effect ”).

(j) Subsidiaries . The subsidiaries set forth on Schedule D (collectively, the “ Subsidiaries ”), are the Company’s only significant subsidiaries (as such term is defined in Rule 1-02 of Regulation S-X promulgated by the Commission). Except as set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus, the Company owns, directly or indirectly, all of the equity interests of the Subsidiaries free and clear of any lien, charge, security interest, encumbrance, right of first refusal or other restriction, and all the equity interests of the Subsidiaries are validly issued and are fully paid, nonassessable and free of preemptive and similar rights. No Subsidiary is currently prohibited, directly or indirectly, from paying any dividends to the Company, from making any other distribution on such Subsidiary’s capital stock, from repaying to the Company any loans or advances to such Subsidiary from the Company or from transferring any of such Subsidiary’s property or assets to the Company or any other Subsidiary of the Company.

(k) No Violation or Default . Neither the Company nor any of its Subsidiaries is (i) in violation of its certificate of incorporation, charter or by-laws or any other organizational documents; (ii) in default, and no event has occurred that, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its Subsidiaries is a party or by which the Company or any of its Subsidiaries is bound or to which any of the property or assets of the Company or any of its Subsidiaries are subject; or (iii) in violation of any law or statute or any judgment, order, rule or regulation of any Governmental Authority (as defined below), except, in the case of each of clauses (ii) and (iii) above, for any such violation or default that would not, individually or in the aggregate, have a Material Adverse Effect. To the Company’s knowledge, no other party under any material contract or other agreement to which it or any of its Subsidiaries is a party is in default in any respect thereunder where such default would have a Material Adverse Effect.

(l) No Material Adverse Change . Subsequent to the respective dates as of which information is given in the Registration Statement, the Pricing Disclosure Package, the Prospectus and the free writing prospectuses, if any (including any document deemed incorporated by reference therein), there has not been (i) any Material Adverse Effect or the occurrence of any development that would reasonably be expected to have a Material Adverse Effect, (ii) any transaction which is material to the Company and the Subsidiaries taken as a whole, (iii) any obligation or liability, direct or contingent (including any off-balance sheet obligations), incurred by the Company or any Subsidiary, which is material to the Company and the Subsidiaries taken as a whole, (iv) any material change in the capital stock or outstanding long-term indebtedness of the Company or any of its Subsidiaries or (v) any dividend or distribution of any kind declared, paid or made on the capital stock of the Company or any Subsidiary, other than in each case above in the ordinary course of business or as otherwise disclosed in the Registration Statement, the

Pricing Disclosure Package or Prospectus (including any document deemed incorporated by reference therein).

(m) Capitalization . The issued and outstanding shares of capital stock of the Company have been validly issued, are fully paid and nonassessable and, other than as disclosed in the Registration Statement, the Pricing Disclosure Package or the Prospectus, are not subject to any preemptive rights, rights of first refusal or similar rights. The Company has an authorized, issued and outstanding capitalization as set forth in the Registration Statement and the Prospectus as of the dates referred to therein (other than the grant of additional options under the Company’s existing option plans, or changes in the number of outstanding shares of Common Stock of the Company due to the issuance of shares upon the exercise or conversion of securities exercisable for, or convertible into, Common Stock outstanding on the date hereof) and such authorized capital stock conforms in all material respects to the description thereof set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus. The description of the securities of the Company in the Registration Statement, the Pricing Disclosure Package and the Prospectus is complete and accurate in all material respects. Except as disclosed in or contemplated by the Registration Statement, the Pricing Disclosure Package or the Prospectus, as of the date referred to therein, the Company does not have outstanding any options to purchase, or any rights or warrants to subscribe for, or any securities or obligations convertible into, or exchangeable for, or any contracts or commitments to issue or sell, any shares of capital stock or other securities.

(n) Authorization; Enforceability . The Company has full legal right, power and authority to enter into this Agreement, the Pre-Funded Warrants, the Common Warrants, the Option Warrants and the Representative Warrants and perform the transactions contemplated hereby. This Agreement has been duly authorized, executed and delivered by the Company and is a legal, valid and binding agreement of the Company enforceable against the Company in accordance with its terms, except to the extent that enforceability may be limited by bankruptcy, insolvency, reorganization, moratorium or similar laws affecting creditors’ rights generally and by general equitable principles. When issued, the Pre-Funded Warrants, the Common Warrants, the Option Warrants and the Representative Warrants will constitute the legal, valid and binding agreement of the Company, including to issue and sell, upon exercise thereof and payment of the respective exercise prices therefor, the number and type of securities of the Company called for thereby in accordance with the terms thereof, and enforceable against the Company in accordance with its terms, except to the extent that enforceability may be limited by bankruptcy, insolvency, reorganization, moratorium or similar laws affecting creditors’ rights generally and by general equitable principles.

(o) Authorization of the Securities . The Shares have been duly authorized for issuance and sale pursuant to this Agreement and, when issued and delivered by the Company against payment therefor pursuant to this Agreement, will be duly and validly issued, fully paid and nonassessable, free and clear of any pledge, mortgage, hypothecation, lien, encumbrance, security interest or other claim, including any statutory or contractual preemptive rights, resale rights, rights of first refusal or other similar rights. The Warrant Shares when issued, paid for and delivered upon due exercise of the Pre-Funded Warrants, the Common Warrants, the Option Warrants and the Representative Warrants, as applicable, have been duly authorized for issuance and sale pursuant to the Pre-Funded Warrants, the Common Warrants, the Option Warrants and the Representative Warrants, as applicable, and, when issued and delivered by the Company against

payment therefor pursuant to the Pre-Funded Warrants, the Common Warrants, the Option Warrants and the Representative Warrants, as applicable, will be duly and validly issued, fully paid and nonassessable, free and clear of any pledge, mortgage, hypothecation, lien, encumbrance, security interest or other claim, including any statutory or contractual preemptive rights, resale rights, rights of first refusal or other similar rights. The Warrant Shares have been reserved for issuance. The Securities, when issued, will conform in all material respects to the description thereof set forth in or incorporated into the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(p) No Consents Required. No consent, approval, authorization, order, registration or qualification of or with any Governmental Authority is required for the execution, delivery and performance by the Company of this Agreement, the Pre-Funded Warrants, the Common Warrants, the Option Warrants and the Representative Warrants and the issuance and sale by the Company of the Securities, except for such consents, approvals, authorizations, orders and registrations or qualifications as may be required under applicable state securities laws or by the by laws and rules of the Financial Industry Regulatory Authority (“ FINRA ”) or the Nasdaq Stock Market ( “ Nasdaq ”) in connection with the sale of the Securities.

(q) No Preferential Rights . Except as set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus no person has the right, contractual or otherwise, to require the Company to register under the Securities Act, any Common Stock or shares of any other capital stock or other securities of the Company, or to include any such shares or other securities in the Registration Statement or the offering contemplated thereby, whether as a result of the filing or effectiveness of the Registration Statement or the sale of the Securities as contemplated thereby or otherwise.

(r) Independent Public Accounting Firms . KPMG LLP (the “ Accountant ”), whose report on the consolidated financial statements of the Company are filed with the Commission as part of the Company’s most recent Annual Report on Form 10-K filed with the Commission and incorporated by reference into the Registration Statement, the Pricing Disclosure Package and the Prospectus, are and, during the periods covered by its report, was an independent registered public accounting firm within the meaning of the Securities Act and the Public Company Accounting Oversight Board (United States). To the Company’s knowledge, the Accountant is not in violation of the auditor independence requirements of the Sarbanes-Oxley Act of 2002 (the “ Sarbanes-Oxley Act ”).

(s) No Litigation . Except as set forth in the Registration Statement, the Pricing Disclosure Package or the Prospectus, there are no actions, suits or proceedings by or before any Governmental Authority pending, nor, to the Company’s knowledge, any audits or investigations by or before any Governmental Authority, to which the Company or a Subsidiary is a party or to which any property of the Company or any of its Subsidiaries is the subject that, individually or in the aggregate, if determined adversely to the Company or its Subsidiaries, would reasonably be expected to have a Material Adverse Effect and, to the Company’s knowledge, no such actions, suits, proceedings, audits or investigations are threatened or contemplated by any Governmental Authority or threatened by others; and (i) there are no current or pending audits, investigations, actions, suits or proceedings by or before any Governmental Authority that are required under the Securities Act to be described in the Registration Statement, the Pricing Disclosure Package or

Prospectus that are not so described; and (ii) there are no contracts or other documents that are required under the Securities Act to be filed as exhibits to the Registration Statement that are not so filed.

(t) Consents and Permits . As to each product subject to the jurisdiction of the U.S. Food and Drug Administration (“ FDA ”) or any non-U.S. counterpart that is manufactured, packaged, labeled, tested, distributed, sold, and/or marketed by the Company or any of its Subsidiaries (each such product, a “ Product ”), such Product is being manufactured, packaged, labeled, tested, distributed, sold and/or marketed by the Company or its Subsidiaries in compliance with all applicable Health Care Laws relating to registration, investigational use, premarket clearance, licensure, or application approval, good manufacturing practices, good laboratory practices, good clinical practices, product listing, quotas, labeling, advertising, record keeping and filing of reports, except where the failure to be in compliance would not reasonably be expected to have a Material Adverse Effect. There is no pending, completed or, to the Company’s knowledge, threatened, action (including any lawsuit, arbitration, or legal or administrative or regulatory proceeding, charge, complaint, or investigation) against the Company or any of its Subsidiaries, and none of the Company or any of its Subsidiaries has received any notice, warning letter or other communication from the FDA or any other governmental entity, which (i) contests the premarket clearance, licensure, registration, or approval of, the uses of, the distribution of, the manufacturing or packaging of, the testing of, the sale of, or the labeling and promotion of any Product, (ii) withdraws its approval of, requests the recall, suspension, or seizure of, or withdraws or orders the withdrawal of advertising or sales promotional materials relating to, any Product, (iii) imposes a clinical hold on any clinical investigation by the Company or any of its Subsidiaries, (iv) enjoins production at any facility of the Company or any of its Subsidiaries, (v) enters or proposes to enter into a consent decree of permanent injunction with the Company or any of its Subsidiaries, or (vi) otherwise alleges any violation of any laws, rules or regulations by the Company or any of its Subsidiaries, and which, either individually or in the aggregate, would reasonably be expected to have a Material Adverse Effect. The properties, business and operations of the Company have been and are being conducted in all material respects in accordance with all applicable Health Care Laws. The Company has not been informed by the FDA or any non-U.S. counterpart that the FDA or any non-U.S. counterpart will prohibit the marketing, sale, license or use in the United States or in any other territory any product proposed to be developed, produced or marketed by the Company or any Subsidiary nor has the FDA or any non-U.S. counterpart expressed any concern as to approving or clearing for marketing any product being developed or proposed to be developed by the Company or any Subsidiary. To the Company’s knowledge, there are no legal or governmental proceedings relating to any Health Care Law pending or threatened to which the Company is a party, nor is it aware of any material violations of such acts or regulations by the Company, which would have a Material Adverse Effect. For purposes of this Agreement, “ Health Care Laws ” means: (i) the Federal Food, Drug, and Cosmetic Act and the regulations promulgated thereunder; (ii) all applicable federal, state, local and all applicable foreign health care related fraud and abuse laws, including, without limitation, the U.S. Anti-Kickback Statute (42 U.S.C. Section 1320a-7b(b)), the U.S. Physician Payment Sunshine Act (42 U.S.C. § 1320a-7h), the U.S. Civil False Claims Act (31 U.S.C. Section 3729 et seq.), the criminal False Claims Law (42 U.S.C. § 1320a-7b(a)), all criminal laws relating to health care fraud and abuse, including but not limited to 18 U.S.C. Sections 286 and 287, and the health care fraud criminal provisions under the U.S. Health Insurance Portability and Accountability Act of 1996 (“HIPAA”) (42 U.S.C. Section 1320d et seq.), the exclusion laws (42 U.S.C. § 1320a-7), the civil

monetary penalties law (42 U.S.C. § 1320a-7a), the statutes, regulations and directives of applicable government funded or sponsored healthcare programs, and the regulations promulgated pursuant to such statutes; (iii) the Standards for Privacy of Individually Identifiable Health Information (the “Privacy Rule”), the Security Standards, and the Standards for Electronic Transactions and Code Sets promulgated under HIPAA, the Health Information Technology for Economic and Clinical Health Act (42 U.S.C. Section 17921 et seq.), and the regulations promulgated thereunder and any state or non-U.S. counterpart thereof or other law or regulation the purpose of which is to protect the privacy of individuals or prescribers; (iv) Medicare (Title XVIII of the Social Security Act); (v) Medicaid (Title XIX of the Social Security Act); and (vi) any and all other applicable health care laws and regulations.

(u) Regulatory Filings . Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, neither the Company nor any of its Subsidiaries has failed to file with the applicable Governmental Authority (including the FDA or any foreign, federal, state or local Governmental Authority performing functions similar to those performed by the FDA) any required filing, declaration, listing, registration, report or submission, except for such failures that, individually or in the aggregate, would not reasonably be expected to have a Material Adverse Effect; except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, all such filings, declarations, listings, registrations, reports or submissions were in material compliance with applicable laws when filed and no deficiencies have been asserted by any applicable regulatory authority with respect to any such filings, declarations, listings, registrations, reports or submissions, except for any deficiencies that, individually or in the aggregate, would not have a Material Adverse Effect. The Company has operated and currently is, in all material respects, in compliance with the United States Federal Food, Drug, and Cosmetic Act, all applicable rules and regulations of the FDA, and other federal, state, local and foreign Governmental Authority exercising comparable authority. The Company has no knowledge of any studies, tests or trials not described in the Registration Statement, the Pricing Disclosure Package and the Prospectus the results of which reasonably call into question in any material respect the results of the studies, tests and trials described in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(v) Intellectual Property . Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, the Company and its Subsidiaries own, possess, license or have other rights to use, or could obtain on commercially reasonable terms, all foreign and domestic patents, patent applications, trade and service marks, trade and service mark registrations, trade names, copyrights, licenses, inventions, trade secrets, technology, Internet domain names, know-how and other intellectual property (collectively, the “ Intellectual Property ”), necessary for the conduct of their respective businesses as now conducted except to the extent that the failure to own, possess, license or otherwise hold adequate rights to use such Intellectual Property would not, individually or in the aggregate, have a Material Adverse Effect. Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus (i) there are no rights of third parties to any such Intellectual Property owned by the Company and its Subsidiaries, except for licenses granted in the ordinary course to third parties, or that could not, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect; (ii) to the Company’s knowledge, there is no infringement by third parties of any such Intellectual Property; (iii) there is no pending or, to the Company’s knowledge, threatened action, suit, proceeding or claim by others challenging the Company’s and its Subsidiaries’ rights in or to any such

Intellectual Property, and the Company is unaware of any facts which could form a reasonable basis for any such action, suit, proceeding or claim; (iv) there is no pending or, to the Company’s knowledge, threatened action, suit, proceeding or claim by others challenging the validity or scope of any such Intellectual Property; (v) there is no pending or, to the Company’s knowledge, threatened action, suit, proceeding or claim by others that the Company and its Subsidiaries infringe or otherwise violate any patent, trademark, copyright, trade secret or other proprietary rights of others; (vi) to the Company’s knowledge, there is no third-party U.S. patent or published U.S. patent application which contains claims for which an Interference Proceeding (as defined in 35 U.S.C. § 135), or the equivalent in any other jurisdiction, has been commenced against any patent or patent application described in the Registration Statement, the Pricing Disclosure Package and the Prospectus as being owned by or licensed to the Company; and (vii) the Company and its Subsidiaries have complied with the terms of each agreement pursuant to which Intellectual Property has been licensed to the Company or such Subsidiary, and all such agreements are in full force and effect, except, in the case of any of clauses (i)-(vii) above, for any such infringement by third parties or any such pending or threatened suit, action, proceeding or claim as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(w) Clinical Studies . The preclinical studies and tests and clinical trials described in the Registration Statement, the Pricing Disclosure Package and the Prospectus were, and, if still pending, are being conducted in all material respects in accordance with the experimental protocols, procedures and controls pursuant to, where applicable, accepted professional and scientific standards for products or product candidates comparable to those being developed by the Company; the descriptions of such studies, tests and trials, and the results thereof, contained in the Registration Statement, the Pricing Disclosure Package and the Prospectus are accurate and complete in all material respects; the Company is not aware of any tests, studies or trials not described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, the results of which reasonably call into question the results of the tests, studies and trials described in the Registration Statement, the Pricing Disclosure Package and the Prospectus; and the Company has not received any written notice or correspondence from the FDA or any foreign, state or local Governmental Authority exercising comparable authority or any institutional review board or comparable authority requiring the termination, suspension, clinical hold or material modification of any tests, studies or trials.

(x) No Material Defaults . Neither the Company nor any of the Subsidiaries has defaulted on any installment on indebtedness for borrowed money or on any rental on one or more long-term leases, which defaults, individually or in the aggregate, would reasonably be expected to have a Material Adverse Effect. The Company has not (i) failed to pay any dividend or sinking fund installment on preferred shares or (ii) defaulted on any installment on indebtedness for borrowed money or on any rental on one or more long-term leases, which defaults, individually or in the aggregate, would reasonably be expected to have a Material Adverse Effect.

(y) Certain Market Activities . Neither the Company nor any of its subsidiaries has taken, directly or indirectly, any action designed to or that might cause or result in stabilization or manipulation of the price of the Common Stock or of any other securities, including any “reference security” (as defined in Rule 100 of Regulation M under the Exchange Act ( “ Regulation M” )) with respect to the Common Stock, whether to facilitate the sale or resale of the Securities or

otherwise, and has taken no action which would directly or indirectly violate Regulation M or applicable foreign securities laws and rules.

(z) Broker/Dealer Relationships . Neither the Company nor any of the Subsidiaries (i) is required to register as a “broker” or “dealer” in accordance with the provisions of the Exchange Act or (ii) directly or indirectly through one or more intermediaries, controls or is a “person associated with a member” or “associated person of a member” (within the meaning set forth in the FINRA Manual).

(aa) No Reliance . The Company has not relied upon the Underwriters or legal counsel for the Underwriters for any legal, tax or accounting advice in connection with the offering and sale of the Securities.

(bb) Taxes . The Company and each of its Subsidiaries have filed all federal, state, local and foreign tax returns which have been required to be filed and paid all taxes shown thereon through the date hereof, to the extent that such taxes have become due and are not being contested in good faith, except where the failure to so file or pay would not reasonably be expected to have a Material Adverse Effect. Except as otherwise disclosed in or contemplated by the Registration Statement, the Pricing Disclosure Package or the Prospectus, no tax deficiency has been determined adversely to the Company or any of its Subsidiaries which has had, or would reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect. The Company has no knowledge of any federal, state, or other governmental tax deficiency, penalty or assessment which has been or might be asserted or threatened against it which would reasonably be expected to have a Material Adverse Effect.

(cc) Title to Real and Personal Property . The Company and its Subsidiaries do not own any real property. Except as set forth in the Registration Statement, the Pricing Disclosure Package or the Prospectus, the Company and its Subsidiaries have good and valid title to all personal property described in the Registration Statement, the Pricing Disclosure Package or the Prospectus as being owned by them that are material to the businesses of the Company or such Subsidiary, in each case free and clear of all mortgages, liens, encumbrances and claims, except those matters that (i) do not materially interfere with the use made and proposed to be made of such property by the Company and any of its Subsidiaries or (ii) would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect. Any real or personal property described in the Registration Statement, the Pricing Disclosure Package or the Prospectus as being leased by the Company and any of its Subsidiaries is held by them under valid, existing and enforceable leases, except those that (A) do not materially interfere with the use made or proposed to be made of such property by the Company or any of its Subsidiaries or (B) would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect. Each of the leased properties of the Company and its Subsidiaries complies with all applicable codes, laws and regulations (including, without limitation, building and zoning codes, laws and regulations and laws relating to access to such properties), except if and to the extent disclosed in the Registration Statement, the Pricing Disclosure Package or the Prospectus or except for such failures to comply that would not, individually or in the aggregate, reasonably be expected to interfere in any material respect with the use made and proposed to be made of such property by the Company and its Subsidiaries or otherwise have a Material Adverse Effect. None of the Company or its subsidiaries has received from any Governmental Authorities any notice of any condemnation of, or zoning change affecting, the properties of the Company and its Subsidiaries, and the Company knows of

no such condemnation or zoning change which is threatened, except for such that would not reasonably be expected to interfere in any material respect with the use made and proposed to be made of such property by the Company and its Subsidiaries or otherwise have a Material Adverse Effect, individually or in the aggregate.

(dd) Environmental Laws . Except as set forth in the Registration Statement, the Pricing Disclosure Package or the Prospectus, the Company and its Subsidiaries (i) are in compliance with any and all applicable federal, state, local and foreign laws, rules, regulations, decisions and orders relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants (collectively, “ Environmental Laws ”); (ii) have received and are in compliance with all permits, licenses or other approvals required of them under applicable Environmental Laws to conduct their respective businesses as described in the Registration Statement, the Pricing Disclosure Package or the Prospectus; and (iii) have not received notice of any actual or potential liability for the investigation or remediation of any disposal or release of hazardous or toxic substances or wastes, pollutants or contaminants, except, in the case of any of clauses (i), (ii) or (iii) above, for any such failure to comply or failure to receive required permits, licenses, other approvals or liability as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(ee) Disclosure Controls . Except as set forth in the Registration Statement, the Pricing Disclosure Package or the Prospectus, the Company and each of its Subsidiaries maintain systems of internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles and to maintain asset accountability; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences. The Company’s internal control over financial reporting is effective and the Company is not aware of any material weaknesses in its internal control over financial reporting (other than as set forth in the Registration Statement, Pricing Disclosure Package or Prospectus). Since the date of the latest audited financial statements of the Company included in the Prospectus, there has been no change in the Company’s internal control over financial reporting that has materially affected, or is reasonably likely to materially affect, the Company’s internal control over financial reporting (other than as set forth in the Registration Statement, Pricing Disclosure Package or Prospectus). Except as set forth in the Registration Statement, the Pricing Disclosure Package or the Prospectus, the Company has established disclosure controls and procedures (as defined in Exchange Act Rules 13a-15 and 15d-15) for the Company and designed such disclosure controls and procedures to ensure that material information relating to the Company and each of its Subsidiaries is made known to the certifying officers by others within those entities, particularly during the period in which the Company’s Annual Report on Form 10-K or Quarterly Report on Form 10-Q, as the case may be, is being prepared. The Company’s certifying officers have evaluated the effectiveness of the Company’s disclosure controls and procedures as of December 31, 2018 (such date, the “ Evaluation Date ”). The Company presented in its Form 10-K for the fiscal year most recently ended the conclusions of the certifying officers about the effectiveness of the disclosure controls and procedures based on their evaluations as of the Evaluation Date and except as set forth in the Registration Statement, the Pricing Disclosure Package or the Prospectus, the disclosure controls

and procedures are effective. Since the Evaluation Date, there have been no significant changes in the Company’s internal controls (as such term is defined in Item 307(b) of Regulation S-K under the Securities Act).

(ff) Sarbanes-Oxley . Since February 13, 2018, there is and has been no failure on the part of the Company or any of the Company’s directors or officers, in their capacities as such, to comply in all material respects with any applicable provisions of the Sarbanes-Oxley Act and the rules and regulations promulgated thereunder.

(gg) Brokers . Neither the Company nor any of the Subsidiaries has incurred any liability for any finder’s fees, brokerage commissions or similar payments in connection with the transactions herein contemplated, except as may otherwise exist with respect to or pursuant to this Agreement.

(hh) Labor Disputes and Matters . Neither the Company or any of its Subsidiaries employs any person represented by a union or collective bargaining unit. No labor disturbance by or dispute with employees of the Company or any of its Subsidiaries exists or, to the knowledge of the Company, is threatened which would reasonably be expected to have a Material Adverse Effect.

(ii) Investment Company Act. Neither the Company nor any of the Subsidiaries is, or will be, either after receipt of payment for the Securities or after the application of the proceeds therefrom as described under “Use of Proceeds” in the Registration Statement, the Pricing Disclosure Package or the Prospectus, required to register as an “investment company” or an entity “controlled” by an “investment company,” as such terms are defined in the Investment Company Act of 1940, as amended (the “Investment Company Act”) .

(jj) Operations . The operations of the Company and its Subsidiaries are and have been conducted at all times in material compliance with applicable financial record keeping and reporting requirements of applicable law, including the Currency and Foreign Transactions Reporting Act of 1970, as amended, the money laundering statutes of all jurisdictions to which the Company or its Subsidiaries are subject, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any Governmental Authority (collectively, the “ Money Laundering Laws ”); and no action, suit or proceeding by or before any Governmental Authority involving the Company or any of its Subsidiaries with respect to the Money Laundering Laws is pending or, to the knowledge of the Company, threatened.

(kk) Off-Balance Sheet Arrangements . There are no transactions, arrangements and other relationships between and/or among the Company, and/or any of its affiliates and any unconsolidated entity, including, but not limited to, any structural finance, special purpose or limited purpose entity (each, an “ Off-Balance Sheet Transaction ”) that would affect materially the Company’s liquidity or the availability of or requirements for its capital resources, including those Off-Balance Sheet Transactions described in the Commission’s Statement about Management’s Discussion and Analysis of Financial Conditions and Results of Operations (Release Nos. 33-8056; 34-45321; FR-61), required to be described in the Registration Statement, the Pricing Disclosure Package or the Prospectus which have not been described as required.

(ll) ERISA . To the knowledge of the Company, each employee benefit plan, within the meaning of Section 3(3) of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), that is maintained, administered or contributed to by the Company or any of its affiliates for employees or former employees of the Company and any of its Subsidiaries has been maintained in compliance with its terms and the requirements of any applicable statutes, orders, rules and regulations, including but not limited to ERISA and the Internal Revenue Code of 1986, as amended (the “Code”) except where the failure to so maintain in compliance would result in a Material Adverse Effect; no prohibited transaction, within the meaning of Section 406 of ERISA or Section 4975 of the Code, has occurred which would result in a material liability to the Company with respect to any such plan excluding transactions effected pursuant to a statutory or administrative exemption; and for each such plan that is subject to the funding rules of Section 412 of the Code or Section 302 of ERISA, no “accumulated funding deficiency” as defined in Section 412 of the Code has been incurred, whether or not waived, and the fair market value of the assets of each such plan (excluding for these purposes accrued but unpaid contributions) exceeds the present value of all benefits accrued under such plan determined using reasonable actuarial assumptions.

(mm) Forward-Looking Statements. Each financial or operational projection or other “forward-looking statement” (as defined by Section 27A of the Securities Act or Section 21E of the Exchange Act, or as defined by any other applicable securities laws) contained in the Registration Statement, the Pricing Disclosure Package or the Prospectus (i) was so included by the Company in good faith and with reasonable basis after due consideration by the Company of the underlying assumptions, estimates and other applicable facts and circumstances and (ii) is accompanied by meaningful cautionary statements identifying those factors that could cause actual results to differ materially from those in such forward-looking statement. No such statement was made with the knowledge of an executive officer or director of the Company that it was false or misleading.

(nn) Margin Rules . Neither the issuance, sale and delivery of the Securities nor the application of the proceeds thereof by the Company as described in the Registration Statement and the Prospectus will violate Regulation T, U or X of the Board of Governors of the Federal Reserve System or any other regulation of such Board of Governors.

(oo) Insurance . The Company and each of its Subsidiaries carry, or are covered by, insurance in such amounts and covering such risks as the Company and each of its Subsidiaries reasonably believe are adequate for the conduct of their business and as is customary for companies engaged in similar businesses in similar industries.

(pp) No Improper Practices . (i) Neither the Company nor the Subsidiaries, nor any director, officer, or employee of the Company or any Subsidiary nor, to the Company’s knowledge, any agent, affiliate or other person acting on behalf of the Company or any Subsidiary has, in the past five years, made any unlawful contributions to any candidate for any political office (or failed fully to disclose any contribution in violation of applicable law) or made any contribution or other payment to any official of, or candidate for, any federal, state, municipal, or foreign office or other person charged with similar public or quasi-public duty in violation of any applicable law or of the character required to be disclosed in the Prospectus; (ii) no relationship, direct or indirect, exists between or among the Company or any Subsidiary or any affiliate of any of them, on the one hand, and the directors, officers and stockholders of the Company or any Subsidiary, on the other hand,

that is required by the Securities Act to be described in the Registration Statement, the Pricing Disclosure Package and the Prospectus that is not so described; (iii) no relationship, direct or indirect, exists between or among the Company or any Subsidiary or any affiliate of them, on the one hand, and the directors, officers, or stockholders of the Company or any Subsidiary, on the other hand, that is required by the rules of FINRA to be described in the Registration Statement, the Pricing Disclosure Package and the Prospectus that is not so described; (iv) except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there are no material outstanding loans or advances or material guarantees of indebtedness by the Company or any Subsidiary to or for the benefit of any of their respective officers or directors or any of the members of the families of any of them; and (v) the Company has not offered, or caused any placement agent to offer, Common Stock to any person with the intent to influence unlawfully (A) a customer or supplier of the Company or any Subsidiary to alter the customer’s or supplier’s level or type of business with the Company or any Subsidiary or (B) a trade journalist or publication to write or publish favorable information about the Company or any Subsidiary or any of their respective products or services, and, (vi) neither the Company nor any Subsidiary nor any director, officer or employee of the Company or any Subsidiary nor, to the Company’s knowledge, any agent, affiliate or other person acting on behalf of the Company or any Subsidiary has (A) violated or is in violation of any applicable provision of the U.S. Foreign Corrupt Practices Act of 1977, as amended, or any other applicable anti-bribery or anti-corruption law (collectively, “ Anti-Corruption Laws ”), (B) promised, offered, provided, attempted to provide or authorized the provision of anything of value, directly or indirectly, to any person for the purpose of obtaining or retaining business, influencing any act or decision of the recipient or securing any improper advantage, or (C) made any payment of funds of the Company or any Subsidiary or received or retained any funds in violation of any Anti-Corruption Laws.

(qq) No Conflicts . Neither the execution of this Agreement, nor the issuance, offering or sale of the Securities, nor the consummation of any of the transactions contemplated herein and therein, nor the compliance by the Company with the terms and provisions hereof and thereof will conflict with, or will result in a breach of, any of the terms and provisions of, or has constituted or will constitute a default under, or has resulted in or will result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company pursuant to the terms of any contract or other agreement to which the Company may be bound or to which any of the property or assets of the Company is subject, except (i) such conflicts, breaches or defaults as may have been waived and (ii) such conflicts, breaches and defaults that would not reasonably be expected to have a Material Adverse Effect; nor will such action result (x) in any violation of the provisions of the organizational or governing documents of the Company, or (y) in any violation of the provisions of any statute or any order, rule or regulation applicable to the Company or of any Governmental Authority having jurisdiction over the Company other than, with respect to clause (y) only, any violation that would not have a Material Adverse Effect; provided, however, that such violation shall not have any adverse effect with respect to the Underwriter.

(rr) Sanctions . (i) The Company represents that, neither the Company nor any of its Subsidiaries (collectively, the “ Entity ”) or any director, officer, employee, agent, affiliate or representative of the Entity, is a government, individual, or entity (in this paragraph (rr), “ Person ”) that is, or is owned or controlled by a Person that is:

(A) the subject of any sanctions administered or enforced by the U.S. Department of Treasury’s Office of Foreign Assets Control (“ OFAC ”), the United Nations Security Council, the European Union, Her Majesty’s Treasury, or other relevant sanctions authorities, including designation on OFAC’s Specially Designated Nationals and Blocked Persons List, OFAC’s Foreign Sanctions Evaders List or other similar applicable legislation or rules (as amended, collectively, “ Sanctions ”), nor

(B) located, organized or resident in a country or territory that is the subject of Sanctions that broadly prohibit dealings with that country or territory (including Cuba, Iran, North Korea, Sudan, Syria and the Crimea Region of the Ukraine) (the “ Sanctioned Countries ”).

(ii) The Entity represents and covenants that it will not, directly or indirectly, use the proceeds of the offering, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other Person:

(A) to fund or facilitate any activities or business of or with any Person or in any country or territory that, at the time of such funding or facilitation, is the subject of Sanctions or is a Sanctioned Country; or

(B) in any other manner that will result in a violation of Sanctions by any Person (including any Person participating in the offering, whether as underwriter, advisor, investor or otherwise).

(iii) The Entity represents and covenants that, except as detailed in the Registration Statement and the Prospectus, for the past 5 years, it has not engaged in, is not now engaging in, and will not engage in, any dealings or transactions with any Person, or in any country or territory, that at the time of the dealing or transaction is or was the subject of Sanctions or is or was a Sanctioned Country.

(ss) Compliance with Laws . Each of the Company and its Subsidiaries: (i) is and at all times has been in compliance with all statutes, rules, or regulations applicable to the ownership, testing, development, manufacture, packaging, processing, use, distribution, marketing, labeling, promotion, sale, offer for sale, storage, import, export or disposal of any product manufactured or distributed by the Company or its Subsidiaries (“ Applicable Laws ”), except as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; (ii) has not received any FDA Form 483, notice of adverse finding, warning letter, untitled letter or other correspondence or notice from the FDA or any other Governmental Authority alleging or asserting noncompliance with any Applicable Laws or any licenses, certificates, approvals, clearances, authorizations, permits and supplements or amendments thereto required by any such Applicable Laws (“ Authorizations ”); (iii) possesses all Authorizations and such Authorizations are valid and in full force and effect and are not in violation of any term of any such Authorizations except where the failure to be so would have a Material Adverse Effect; (iv) has not received notice of any claim, action, suit, proceeding, hearing, enforcement, investigation, arbitration or other action from any Governmental Authority or third party alleging that any product operation or activity is in violation of any Applicable Laws or Authorizations and has no knowledge that any such Governmental Authority or third party is considering any such claim, litigation, arbitration, action, suit,

investigation or proceeding; (v) has not received notice that any Governmental Authority has taken, is taking or intends to take action to limit, suspend, modify or revoke any Authorizations and has no knowledge that any such Governmental Authority is considering such action; (vi) has filed, obtained, maintained or submitted all material reports, documents, forms, notices, applications, records, claims, submissions and supplements or amendments as required by any Applicable Laws or Authorizations and that all such reports, documents, forms, notices, applications, records, claims, submissions and supplements or amendments were complete and correct on the date filed (or were corrected or supplemented by a subsequent submission); and (vii) other than the voluntary field corrective action with respect to MGuard Prime in 2014, as previously publicly disclosed, has not, either voluntarily or involuntarily, initiated, conducted, or issued or caused to be initiated, conducted or issued, any recall, market withdrawal or replacement, safety alert, post sale warning, “dear healthcare provider” letter, or other notice or action relating to the alleged lack of safety or efficacy of any product or any alleged product defect or violation and, to the Company’s knowledge, no third party has initiated, conducted or intends to initiate any such notice or action.

(tt) Statistical and Market-Related Data . All statistical, demographic and market-related data included in the Registration Statement, the Pricing Disclosure Package or the Prospectus are based on or derived from sources that the Company believes to be reliable and accurate or represent the Company’s good faith estimates that are made on the basis of data derived from such sources.

(uu) Stock Exchange Listing . The Common Stock is registered pursuant to Section 12(b) of the Exchange Act and is listed, and the Company has taken no action designed to, or likely to have the effect of, terminating the registration of the Common Stock under the Exchange Act or delisting the Common Stock from Nasdaq. Except as set forth in the Registration Statement, the Pricing Disclosure Package or the Prospectus, the Company has not received any notification that the Commission or Nasdaq is contemplating terminating such registration or listing. Except as set forth in the Registration Statement, the Pricing Disclosure Package or the Prospectus, to the Company’s knowledge, it is in compliance with all applicable listing requirements of Nasdaq.

(vv) Related-Party Transactions . There are no business relationships or related-party transactions involving the Company or any of its subsidiaries or any other person required to be described in the Registration Statement, the Pricing Disclosure Package or the Prospectus that have not been described as required.

(ww) FINRA Matters . All of the information provided to the Underwriters or to counsel for the Underwriters by the Company, its counsel, its officers and directors and the holders of any securities (debt or equity) or options to acquire any securities of the Company in connection with the offering of the Securities is true, complete, correct and compliant with FINRA’s rules and any letters, filings or other supplemental information provided to FINRA pursuant to FINRA Rules is true, complete and correct.

(xx) Parties to Lock-Up Agreements . The Company has furnished to the Underwriters a letter agreement in the form attached hereto as Exhibit A (the “ Lock-up Agreement ”) from each of the persons listed on Exhibit B . Such Exhibit B lists under an appropriate caption the directors and executive officers and certain other stockholders of the Company. If any additional persons shall become directors or executive officers of the Company prior to the end of the Company Lock-

up Period (as defined below), the Company shall cause each such person, prior to or contemporaneously with their appointment or election as a director or executive officer of the Company, to execute and deliver to Wainwright a Lock-up Agreement.

(aaa) No Rights to Purchase Shares. Except as set forth in the Registration Statement, the Pricing Disclosure Package or the Prospectus, the issuance and sale of the Securities as contemplated hereby will not cause any holder of any shares of capital stock, securities convertible into or exchangeable or exercisable for capital stock or options, warrants or other rights to purchase shares or any other securities of the Company to have any right to acquire any shares of capital stock of the Company.

(ccc) [Reserved]

(ddd) Integration . Neither the Company, nor any of its affiliates, nor any person acting on its or their behalf has, directly or indirectly, made any offers or sales of any security or solicited any offers to buy any security, under circumstances that would cause the offering of the Securities to be integrated with prior offerings by the Company for purposes of the Securities Act that would require the registration of any such securities under the Securities Act.

Any certificate signed by any officer of the Company or any of its subsidiaries and delivered to any Underwriter or to counsel for the Underwriters in connection with the offering, or the purchase and sale, of the Securities shall be deemed a representation and warranty by the Company to each Underwriter as to the matters covered thereby.

The Company has a reasonable basis for making each of the representations set forth in this Section 1. The Company acknowledges that the Underwriters and, for purposes of the opinions to be delivered pursuant to Section 6 hereof, counsel to the Company and counsel to the Underwriters, will rely upon the accuracy and truthfulness of the foregoing representations and hereby consents to such reliance.

2. Purchase, Sale and Delivery of the Securities .

(a) The Firm Securities . Subject to the terms and conditions herein set forth, the Company agrees to sell to the several Underwriters, and on the basis of the representations, warranties and agreements herein contained and upon the terms but subject to the conditions herein set forth, the Underwriters agree to purchase from the Company, (i) at a combined purchase price for one Share and a Common Warrant of $[ · ], which shall be allocated as $[ · ] per Share (the “ Per Share Purchase Price ”) and $[ · ] per Common Warrant (the “ Per Common Warrant Purchase Price ”) and (ii) at a combined purchase price for one Pre-Funded Warrant and a Common Warrant of $[ · ] which shall be allocated as $[ · ] per Pre-Funded Warrant and $[ · ] per Common Warrant.

(b) The Closing Date . Delivery of book-entry entitlements for the Firm Securities to be purchased by the Underwriters and payment therefor shall be made at the offices of McDermott Will & Emery, LLP, 340 Madison Ave, New York, NY 10173 (or such other place as may be agreed to by the Company and the Representative) at 10:00 a.m. Eastern time, on April [ · ], 2019, or such other time and date not later than 1:00 p.m. Eastern time, on April [ · ], 2019, as the Representative shall designate by notice to the Company (the time and date of such closing are called the “ Closing Date ”). The Company hereby acknowledges that circumstances under

which the Representative may provide notice to postpone the Closing Date as originally scheduled include, but are not limited to, any determination by the Company or the Representative to recirculate to the public copies of an amended or supplemented Prospectus or a delay as contemplated by the provisions of Section 10.

(c) The Option Shares and Option Warrants; Option Closing Date . In addition, on the basis of the representations, warranties and agreements herein contained, and upon the terms but subject to the conditions herein set forth, the Company hereby grants an option to the several Underwriters to purchase, severally and not jointly, i) up to any combination of [ · ] Option Shares and/or [ · ] Option Warrants at the Per Share Purchase Price and/or the Per Common Warrant Purchase Price, respectively. The option granted hereunder may be exercised at any time and from time to time in whole or in part upon notice by the Representative to the Company, which notice may be given at any time within 30 days from the date of this Agreement. Such notice shall set forth (i) the aggregate number of Option Shares and/or Option Warrants as to which the Underwriters are exercising the option and (ii) the time, date and place at which book-entry entitlements for the Option Shares and/or Option Warrants will be delivered (which time and date may be simultaneous with, but not earlier than, the Closing Date; and in the event that such time and date are simultaneous with the Closing Date, the term “Closing Date” shall refer to the time and date of delivery of book-entry entitlements for the Firm Securities and such Option Securities). Any such time and date of delivery, if subsequent to the Closing Date, is called an “ Option Closing Date ,” shall be determined by the Representative and shall not be earlier than three or later than five full business days after delivery of such notice of exercise.

If any Option Share and/or Option Warrants are to be purchased, (a) each Underwriter agrees, severally and not jointly, to purchase the number of Option Securities (subject to such adjustments to eliminate fractional shares as the Representative may determine) that bears the same proportion to the total number of Option Securities to be purchased as the number of Firm Securities set forth on Schedule A opposite the name of such Underwriter bears to the total number of Firm Securities and (b) the Company agrees to sell the number of Option Securities set forth in the paragraph “Introductory” of this Agreement (subject to such adjustments to eliminate fractional shares as the Representative may determine). The Representative may cancel the option at any time prior to its expiration by giving written notice of such cancellation to the Company.

(d) Public Offering of the Securities . The Representative hereby advises the Company that the Underwriters intend to offer for sale to the public, initially on the terms set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus, their respective portions of the Securities as soon after this Agreement has been executed as the Representative, in its sole judgment, has determined is advisable and practicable.

(e) Payment for the Securities . Payment for the Firm Securities shall be made at the Closing Date (and, if applicable, the Option Securities at each Option Closing Date) by wire transfer of immediately available funds to the order of the Company. It is understood that the Representative has been authorized, for its own account and the accounts of the several Underwriters, to accept delivery of and receipt for, and make payment of the purchase price for, the Firm Securities and any Option Securities the Underwriters have agreed to purchase. Wainwright, individually and not as the Representative of the Underwriters, may (but shall not be obligated to) make payment for any Firm Securities and any Option Securities to be purchased by any Underwriter whose funds shall not have been received by the Representative by the Closing

Date or the applicable Option Closing Date, as the case may be, for the account of such Underwriter, but any such payment shall not relieve such Underwriter from any of its obligations under this Agreement.

(f) Delivery of the Securities . The Company shall deliver, or cause to be delivered through the facilities of DTC unless the Representative shall otherwise instruct, to the Representative for the accounts of the several Underwriters, book-entry entitlements for the Firm Shares at the Closing Date, against the irrevocable release of a wire transfer of immediately available funds for the amount of the purchase price therefor. The Company will deliver the certificates for the Pre-Funded Warrants, against payment of the purchase price therefor, in definitive form, in such denominations and registered in such names as the Underwriter or its designees request, to the purchasers thereof on the Closing Date. In the event that a purchaser delivers a Notice of Exercise (as defined in the Pre-Funded Warrants) on or prior to 12:00 P.M., New York time on the Closing Date, to exercise any Pre-Funded Warrants between the date hereof and the Closing Date, the Company shall deliver Warrant Shares with respect to such Pre-Funded Warrants to such purchaser on the Closing Date in connection with such Notice of Exercise. The Firm Shares and/or Pre-Funded Warrants will be issued separately and may be transferred separately immediately upon issuance.

The Company shall also deliver, or cause to be delivered through the facilities of DTC unless the Representative shall otherwise instruct, to the Representative for the accounts of the several Underwriters, book-entry entitlements for the Option Shares and/or Option Warrants the Underwriters have agreed to purchase at the Closing Date or the applicable Option Closing Date, as the case may be, against the irrevocable release of a wire transfer of immediately available funds for the amount of the purchase price therefor. The Option Shares and/or Option Warrants will be issued separately and may be transferred separately immediately upon issuance.

If the Representative so elects, delivery of the Shares will be made by credit to the accounts designated by the Representative through DTC’s full fast transfer or DWAC programs. Time shall be of the essence, and delivery at the time and place specified in this Agreement is a further condition to the obligations of the Underwriters.

(g) Representative Warrants . The Company shall issue to Wainwright or its designees on each of the Closing Date and each Option Closing Date, the Representative Warrants, which represent warrants to purchase that number of shares of Common Stock equal to 7.0% of the aggregate number of (i) shares of Common Stock issued, and (ii) shares of Common Stock issuable upon exercise of the Pre-Funded Warrants issued on each of the Closing Date and each Option Closing Date. The Representative Warrants shall be in the form filed as an exhibit to the Initial Registration Statement, shall be exercisable, in whole or in part, immediately and expire on the five-year anniversary of the date of effectiveness of the Initial Registration Statement at an initial exercise price per share of Common Stock of $[ · ], which is equal to 125% of the initial public offering price of the shares of Common Stock. The Representative Warrants shall be subject to the limitation on exercise set forth in FINRA Rule 5110(f)(2)(G)(i); provided, however that pursuant to FINRA Rule 5110(g)(1) the Representative Warrants shall not be sold, transferred, assigned, pledged, or hypothecated, or be the subject of any hedging, short sale, derivative, put, or call transaction that would result in the effective economic disposition of the securities by any person for a period of 180 days immediately following the date of the date of effectiveness of the

registration statement referred to in Section 1(a) hereof, except for the transfers enumerated in FINRA Rule 5110(g)(2).

3. Additional Covenants of the Company .

The Company further covenants and agrees with each Underwriter as follows:

(a) Delivery of Registration Statement, Pricing Disclosure Package and Prospectus . The Company shall furnish to you in New York City, without charge, prior to 10:00 a.m. New York City time on the business day next succeeding the date of this Agreement and during the period when a prospectus relating to the Securities is required by the Securities Act to be delivered (whether physically or through compliance with Rule 172 under the Securities Act or any similar rule) in connection with sales of the Securities, as many copies of the Pricing Disclosure Package, the Prospectus and any supplements and amendments thereto or to the Registration Statement as you may reasonably request.

(b) Representative’s Review of Proposed Amendments and Supplements . During the period when a prospectus relating to the Securities is required by the Securities Act to be delivered (whether physically or through compliance with Rule 172 under the Securities Act or any similar rule), the Company (i) will furnish to the Representative for review, a reasonable period of time prior to the proposed time of filing of any proposed amendment or supplement to the Registration Statement, a copy of each such amendment or supplement and (ii) will not amend or supplement the Registration Statement (including any amendment or supplement through incorporation of any report filed under the Exchange Act) without the Representative’s prior written consent, not to be unreasonably withheld, conditioned or delayed. Prior to amending or supplementing any preliminary prospectus, the Pricing Disclosure Package or the Prospectus (including any amendment or supplement through incorporation of any report filed under the Exchange Act), the Company shall furnish to the Representative for review, a reasonable amount of time prior to the time of filing or use of the proposed amendment or supplement, a copy of each such proposed amendment or supplement. The Company shall not file or use any such proposed amendment or supplement without the Representative’s prior written consent, not to be unreasonably withheld, conditioned or delayed. The Company shall file with the Commission within the applicable period specified in Rule 424(b) under the Securities Act any prospectus required to be filed pursuant to such Rule.

(c) Free Writing Prospectuses . The Company shall furnish to the Representative for review, a reasonable amount of time prior to the proposed time of filing or use thereof, a copy of each proposed free writing prospectus or any amendment or supplement thereto prepared by or on behalf of, used by, or referred to by the Company, and the Company shall not file, use or refer to any proposed free writing prospectus or any amendment or supplement thereto without the Representative’s prior written consent, not to be unreasonably withheld, conditioned or delayed. The Company shall furnish to each Underwriter, without charge, as many copies of any free writing prospectus prepared by or on behalf of, used by or referred to by the Company as such Underwriter may reasonably request. If at any time when a prospectus is required by the Securities Act to be delivered (whether physically or through compliance with Rule 172 under the Securities Act or any similar rule) in connection with sales of the Securities (but in any event if at any time through and including the Closing Date) there occurred or occurs an event or development as a result of which any free writing prospectus prepared by or on behalf of, used by, or referred

to by the Company conflicted or would conflict with the information contained in the Registration Statement or included or would include an untrue statement of a material fact or omitted or would omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances prevailing at such time, not misleading, the Company shall promptly amend or supplement such free writing prospectus to eliminate or correct such conflict so that the statements in such free writing prospectus as so amended or supplemented will not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances prevailing at such time, not misleading, as the case may be; provided, however , that prior to amending or supplementing any such free writing prospectus, the Company shall furnish to the Representative for review, a reasonable amount of time prior to the proposed time of filing or use thereof, a copy of such proposed amended or supplemented free writing prospectus, and the Company shall not file, use or refer to any such amended or supplemented free writing prospectus without the Representative’s prior written consent, not to be unreasonably withheld, conditioned or delayed.

(d) Filing of Underwriter Free Writing Prospectuses . The Company shall not take any action that would result in an Underwriter or the Company being required to file with the Commission pursuant to Rule 433(d) under the Securities Act a free writing prospectus prepared by or on behalf of such Underwriter that such Underwriter otherwise would not have been required to file thereunder.

(e) Amendments and Supplements to Pricing Disclosure Package . If the Pricing Disclosure Package is being used to solicit offers to buy the Securities at a time when the Prospectus is not yet available to prospective purchasers, and any event shall occur or condition exist as a result of which it is necessary to amend or supplement the Pricing Disclosure Package so that the Pricing Disclosure Package does not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances when delivered to a prospective purchaser, not misleading, or if any event shall occur or condition exist as a result of which the Pricing Disclosure Package conflicts with the information contained in the Registration Statement, or if, in the opinion of counsel for the Underwriters, it is necessary to amend or supplement the Pricing Disclosure Package to comply with applicable law, the Company shall (subject to Section 3(b) and Section 3(c) hereof) promptly prepare, file with the Commission and furnish, at its own expense, to the Underwriters and to any dealer upon request, either amendments or supplements to the Pricing Disclosure Package so that the statements in the Pricing Disclosure Package as so amended or supplemented will not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances when delivered to a prospective purchaser, not misleading or so that the Pricing Disclosure Package, as amended or supplemented, will no longer conflict with the information contained in the Registration Statement, or so that the Pricing Disclosure Package, as amended or supplemented, will comply with applicable law.

(f) Certain Notifications and Required Actions . During the period when a prospectus relating to the Securities is required by the Securities Act to be delivered (whether physically or through compliance with Rule 172 under the Securities Act or any similar rule), the Company shall promptly advise the Representative in writing of: (i) the receipt of any comments of, or requests for additional or supplemental information from, the Commission; (ii) the time and date of any filing of any post-effective amendment to the Registration Statement or any

amendment or supplement to any preliminary prospectus, the Pricing Disclosure Package, any free writing prospectus or the Prospectus; (iii) the time and date that any post-effective amendment to the Registration Statement becomes effective; and (iv) the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or any post-effective amendment thereto or any amendment or supplement to any preliminary prospectus, the Pricing Disclosure Package or the Prospectus or of any order preventing or suspending the use of any preliminary prospectus, the Pricing Disclosure Package, any free writing prospectus or the Prospectus, or of any proceedings to remove, suspend or terminate from listing or quotation the Common Stock from any securities exchange upon which they are listed for trading or included or designated for quotation, or of the threatening or initiation of any proceedings for any of such purposes. If the Commission shall enter any such stop order at any time, the Company will use its best efforts to obtain the lifting of such order as soon as practicable. Additionally, the Company agrees that it shall comply with all applicable provisions of Rule 424(b), Rule 433 and Rule 430B under the Securities Act and will use its reasonable efforts to confirm that any filings made by the Company under Rule 424(b) or Rule 433 were received in a timely manner by the Commission.

(g) Amendments and Supplements to the Prospectus and Other Securities Act Matters . If any event shall occur or condition exist as a result of which it is necessary to amend or supplement the Prospectus so that the Prospectus does not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances when the Prospectus is delivered (whether physically or through compliance with Rule 172 under the Securities Act or any similar rule) to a purchaser, not misleading, or if in the opinion of the Representative or counsel for the Underwriters it is otherwise necessary to amend or supplement the Prospectus to comply with applicable law, the Company agrees (subject to Section 3(b) and Section 3(c) hereof) to promptly prepare, file with the Commission and furnish, at its own expense, to the Underwriters and to any dealer upon request, amendments or supplements to the Prospectus so that the statements in the Prospectus as so amended or supplemented will not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances when the Prospectus is delivered (whether physically or through compliance with Rule 172 under the Securities Act or any similar rule) to a purchaser, not misleading or so that the Prospectus, as amended or supplemented, will comply with applicable law. Neither the Representative’s consent to, nor delivery of, any such amendment or supplement shall constitute a waiver of any of the Company’s obligations under Section 3(b) or Section 3(c).

(h) Blue Sky Compliance . The Company shall cooperate with the Representative and counsel for the Underwriters to qualify or register the Securities for sale under (or obtain exemptions from the application of) the state securities or blue sky laws (or other foreign laws as reasonably requested by the Underwriters and agreed to by the Company) of those jurisdictions designated by the Representative, shall comply in all material respects with such laws and shall continue such qualifications, registrations and exemptions in effect so long as required for the distribution of the Securities. The Company shall not be required to qualify as a foreign corporation or other entity or to take any action that would subject it to general service of process in any such jurisdiction where it is not presently qualified or where it would be subject to taxation as a foreign corporation or other entity. The Company will advise the Representative promptly of the suspension of the qualification or registration of (or any such exemption relating to) the Securities for offering, sale or trading in any jurisdiction or any initiation or threat of any

proceeding for any such purpose, and in the event of the issuance of any order suspending such qualification, registration or exemption, the Company shall use its reasonable best efforts to obtain the withdrawal thereof at the earliest possible moment.

(i) Use of Proceeds . The Company shall apply the net proceeds from the sale of the Securities sold by it in the manner described under the caption “Use of Proceeds” in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(j) Transfer Agent . The Company shall engage and maintain, at its expense, a registrar and transfer agent for the Common Stock.

(k) Earnings Statement . The Company will make generally available (which may be satisfied by filing with EDGAR) to its security holders and to the Representative as soon as practicable an earnings statement (which need not be audited) covering a period of at least twelve months beginning with the first fiscal quarter of the Company commencing after the date of this Agreement that will satisfy the provisions of Section 11(a) of the Securities Act and the rules and regulations of the Commission thereunder.

(l) Continued Compliance with Securities Laws . The Company will comply with the Securities Act and the Exchange Act so as to permit the completion of the distribution of the Securities as contemplated by this Agreement , the Registration Statement, the Pricing Disclosure Package and the Prospectus. Without limiting the generality of the foregoing, the Company will, during the period when a prospectus relating to the Securities is required by the Securities Act to be delivered (whether physically or through compliance with Rule 172 under the Securities Act or any similar rule), file on a timely basis with the Commission and Nasdaq all reports and documents required to be filed under the Exchange Act.

(m) Listing . The Company will use its best efforts to maintain the listing of its shares of Common Stock on Nasdaq.

(n) Company to Provide Copy of the Prospectus in Form That May be Downloaded from the Internet. If requested by the Representative, the Company shall cause to be prepared and delivered, at its expense, within one business day from the effective date of this Agreement, to Wainwright, an “ electronic Prospectus ” to be used by the Underwriters in connection with the offering and sale of the Securities. As used herein, the term “ electronic Prospectus ” means a form of Pricing Disclosure Package, and any amendment or supplement thereto, that meets each of the following conditions: (i) it shall be encoded in an electronic format, satisfactory to Wainwright, that may be transmitted electronically by Wainwright and the other Underwriters to offerees and purchasers of the Securities; (ii) it shall disclose the same information as the paper Pricing Disclosure Package, except to the extent that graphic and image material cannot be disseminated electronically, in which case such graphic and image material shall be replaced in the electronic Prospectus with a fair and accurate narrative description or tabular representation of such material, as appropriate; and (iii) it shall be in or convertible into a paper format or an electronic format, satisfactory to Wainwright, that will allow investors to store and have continuously ready access to the Pricing Disclosure Package at any future time, without charge to investors (other than any fee charged for subscription to the Internet as a whole and for on-line time). The Company hereby confirms that it has included or will include in the Prospectus filed pursuant to EDGAR or otherwise with the Commission and in the Registration Statement at

the time it was declared effective an undertaking that, upon receipt of a request by an investor or his or her representative, the Company shall transmit or cause to be transmitted promptly, without charge, a paper copy of the Pricing Disclosure Package.

(o) Agreement Not to Offer or Sell Common Stock . During the period commencing on and including the date hereof and continuing through and including the 90th day following the date of the Prospectus (such period, as extended as described below, being referred to herein as the “ Lock-up Period ”), the Company will not, without the prior written consent of Wainwright (which consent may be withheld in its sole discretion), directly or indirectly: (i) sell, offer to sell, contract to sell or lend any Common Stock or Related Securities (as defined below); (ii) effect any short sale, or establish or increase any “put equivalent position” (as defined in Rule 16a-1(h) under the Exchange Act) or liquidate or decrease any “call equivalent position “ (as defined in Rule 16a-1(b) under the Exchange Act) of any Common Stock or Related Securities; (iii) pledge, hypothecate or grant any security interest in any Common Stock or Related Securities; (iv) in any other way transfer or dispose of any Common Stock or Related Securities; (v) enter into any swap, hedge or similar arrangement or agreement that transfers, in whole or in part, the economic risk of ownership of any Common Stock or Related Securities, regardless of whether any such transaction is to be settled in securities, in cash or otherwise; (vi) announce the offering of any Common Stock or Related Securities; (vii) file any registration statement under the Securities Act under applicable securities laws in respect of any Common Stock or Related Securities (other than as contemplated by this Agreement with respect to the Securities); or (viii) publicly announce the intention to do any of the foregoing; provided, however , that the Company may (A) effect the transactions contemplated hereby; (B) issue Shares or options to purchase Shares or restricted stock units or similar equity securities, or issue Shares upon exercise of options, restricted stock units or similar equity securities, pursuant to any options, share bonus or other share plan or arrangement pursuant to an incentive plan described in the Registration Statement, the Pricing Disclosure Package and the Prospectus; and (C) file a registration statement on Form S-8 in respect of the issuance, vesting, exercise or settlement of equity awards to officers or directors granted or to be granted pursuant to an incentive plan described in the Registration Statement, Pricing Disclosure Package and the Prospectus (the provisions of clauses (A) through (C) are “ Exempt Issuances ”). For purposes of the foregoing, “ Related Securities ” shall mean any options or warrants or other rights to acquire Common Stock or any securities exchangeable or exercisable for or convertible into Common Stock, or to acquire other securities or rights ultimately exchangeable or exercisable for, or convertible into, Common Stock.

(p) Future Reports to the Representative. During the period of five years hereafter, the Company will furnish to the Representative, c/o Wainwright, at 430 Park Avenue, 4 th Floor, New York, New York 10022, Attention: Head of Investment Banking, with copies to H.C. Wainwright & Co., LLC, 430 Park Avenue, 4 th Floor, New York, New York 10022, Attention: General Counsel: (i) as soon as practicable after the end of each fiscal year, copies of the Annual Report of the Company containing the balance sheet of the Company as of the close of

such fiscal year and statements of income, stockholders’ equity and cash flows for the year then ended and the opinion thereon of the Company’s independent public or certified public accountants; (ii) as soon as practicable after the filing thereof, copies of each proxy statement, Annual Report on Form 10-K, Quarterly Report on Form 10-Q, Current Report on Form 8-K or other report filed by the Company with the Commission, FINRA or any securities exchange; and (iii) as soon as available, copies of any report or communication of the Company furnished or made available generally to holders of its capital stock; provided, however, that the requirements of this Section 3(p) shall be satisfied to the extent that such reports, statement, communications, financial statements or other documents are available on EDGAR.

(q) Investment Limitation . The Company shall not invest or otherwise use the proceeds received by the Company from its sale of the Securities in such a manner as would require the Company or any of its subsidiaries to register as an investment company under the Investment Company Act.

(r) No Stabilization or Manipulation and Compliance with Regulation M . The Company will not take, and will use its reasonable best efforts to ensure that no affiliate of the Company will take, directly or indirectly, without giving effect to activities by the Underwriters, any action designed to or that might cause or result in stabilization or manipulation of the price of the Common Stock or any reference security with respect to the Common Stock, whether to facilitate the sale or resale of the Securities or otherwise, and the Company will, and shall use its reasonable best efforts to cause each of its affiliates to, comply with all applicable provisions of Regulation M.

(s) Enforce Lock-Up Agreements . During the Lock-up Period, the Company will enforce all agreements between the Company and any of its security holders that restrict or prohibit, expressly or in operation, the offer, sale or transfer of Common Stock or Related Securities or any of the other actions restricted or prohibited under the terms of the form of Lock-up Agreement. In addition, the Company will direct the transfer agent to place stop transfer restrictions upon any such securities of the Company that are bound by such “lock-up” agreements for the duration of the periods contemplated in such agreements, including, without limitation, “lock-up” agreements entered into by the Company’s officers and directors and certain other stockholders pursuant to Section 1(xx) hereof.

(t) Right of First Refusal . If, during the 12-month period following the consummation of the offering of the Firm Securities pursuant to this Agreement, the Company or any of its subsidiaries decides to raise funds by means of an underwritten public offering (other than an “at-the-market” facility) or a private placement or any other capital-raising financing of equity, equity-linked or debt securities using an underwriter or placement agent, Representative (or any affiliate designated by Representative) shall have the right to act as (i) for a financing of $15 million or less, sole book-running manager, sole underwriter or sole placement agent for such financing or (ii) for a financing of greater than $15 million, the Company will be entitled to retain other investment banks to participate in such financing, provided that Representative shall act as lead joint book-running manager, co-lead underwriter or co-lead placement agent for such financing. If Representative or one of its affiliates decides to accept any such engagement, the agreement governing such engagement will contain, among other things, provisions for customary fees for transactions of similar size, including indemnification, which are appropriate to such a transaction.

The Representative, on behalf of the several Underwriters, may, in their sole discretion, waive in writing the performance by the Company of any one or more of the foregoing covenants or extend the time for their performance.

4. Payment of Expenses . The Company agrees to pay all costs, fees and expenses incurred in connection with the performance of its obligations hereunder and in connection with the transactions contemplated hereby, including without limitation (i) all expenses incident to the issuance and delivery of the Securities (including all printing and engraving costs), (ii) all fees and expenses of the registrar and transfer agent of the Securities, (iii) all necessary issue, transfer and other stamp taxes in connection with the issuance and sale of the Securities to the Underwriters, (iv) all fees and expenses of the Company’s counsel, independent public or certified public accountants and other advisors, (v) all costs and expenses incurred in connection with the preparation, printing, filing, shipping and distribution of the Registration Statement (including financial statements, exhibits, schedules, consents and certificates of experts), the Pricing Disclosure Package, the Prospectus, each free writing prospectus prepared by or on behalf of, used by, or referred to by the Company, and each Preliminary Prospectus, and all amendments and supplements thereto, and this Agreement, (vi) all filing fees, attorneys’ fees and expenses incurred by the Underwriters in connection with qualifying or registering (or obtaining exemptions from the qualification or registration of) all or any part of the Securities for offer and sale under the state securities or blue sky laws, and, if requested by the Representative, preparing and printing a “Blue Sky Survey” or memorandum, and any supplements thereto, advising the Underwriters of such qualifications, registrations and exemptions, (vii) the costs, fees and expenses incurred by the Underwriters in connection with determining their compliance with the rules and regulations of FINRA related to the Underwriters’ participation in the offering and distribution of the Securities, including any related filings fees and the legal fees of, and disbursements by, counsel to the Underwriters, (viii) the costs and expenses of the Company relating to investor presentations on any “road show”, including, without limitation, expenses associated with the preparation or dissemination of any electronic road show, expenses associated with the production of road show slides and graphics, fees and expenses of any consultants engaged in connection with the road show presentations with the prior approval of the Company, reasonable travel and lodging expenses of the Representative approved by the Company in advance, employees and officers of the Company and any such consultants, (ix) the fees and expenses associated with listing the Securities on Nasdaq, (x) all other fees, costs and expenses of the nature referred to in Item 13 of Part II of the Registration Statement and (xi) all actual and documented out-of-pocket expenses and all fees of the Underwriter’s legal counsel and other out-of-pocket expenses of the Underwriters reasonably incurred in connection with the transactions contemplated hereby; provided, that the amount payable pursuant to the foregoing clauses (vi), (vii), (viii) and (xi) shall not exceed $40,000. Any such amount payable to the Underwriters may be deducted from the purchase price for the Securities.

5. Covenant of the Underwriters . Each Underwriter severally and not jointly covenants with the Company not to take any action that would result in the Company being required to file with the Commission pursuant to Rule 433(d) under the Securities Act a free writing prospectus prepared by or on behalf of such Underwriter that otherwise would not, but for such actions, be required to be filed by the Company under Rule 433(d).

6. Conditions of the Obligations of the Underwriters . The respective obligations of the several Underwriters hereunder to purchase and pay for the Firm Securities as provided herein on the Closing Date and, with respect to the Option Securities, each Option Closing Date, shall be subject to the accuracy of the representations and warranties on the part of the Company set forth in Section 1 hereof as of the date hereof and as of the Closing Date as though then made and, with respect to the Option Securities, as of each Option Closing Date as though then made, to the timely performance by the Company of its covenants and other obligations hereunder, and to each of the following additional conditions:

(a) Comfort Letters. On the Closing Date, the Representative shall have received from KPMG LLP, independent registered public accountants for the Company, a letter dated the date hereof addressed to the Representative, in form and substance satisfactory to the Representative, containing statements and information of the type ordinarily included in accountant’s “comfort letters” to underwriters, delivered according to Statement of Auditing Standards No. 72 (or any successor bulletin), with respect to the audited and unaudited financial statements and certain financial information contained in the Registration Statement, the Pricing Disclosure Package, and each free writing prospectus, if any.

(b) Compliance with Registration Requirements; No Stop Order; No Objection from FINRA. For a period from and after the date of this Agreement and through and including the Closing Date and, with respect to any Option Securities purchased after the Closing Date, each Option Closing Date:

(i) The Company shall have filed the Prospectus with the Commission (including the information required by Rule 430A under the Securities Act) in the manner and within the time period required by Rule 424(b) under the Securities Act; or the Company shall have filed a post-effective amendment to the Registration Statement containing the information required by such Rule 430A, and such post-effective amendment shall have become effective.

(ii) No stop order suspending the effectiveness of the Registration Statement or any post-effective amendment to the Registration Statement shall be in effect, and no proceedings for such purpose shall have been instituted or threatened by the Commission.

(iii) FINRA shall have raised no objection to the fairness and reasonableness of the underwriting terms and arrangements.

(c) No Material Adverse Change or Ratings Agency Change. For the period from and after the date of this Agreement and through and including the Closing Date and, with respect to any Option Securities purchased after the Closing Date, each Option Closing Date, in the judgment of the Representative there shall not have occurred any material adverse change in the authorized capital stock of the Company or any Material Adverse Effect or any development that would cause a Material Adverse Effect.

(d) Opinion of Counsel for the Company. On the Closing Date and each Option Closing Date the Representative shall have received (i) an opinion and negative assurance letter of Cooley LLP, counsel for the Company, dated as of such date in form and substance satisfactory to the Representative, dated as of such date, and (ii) an opinion from Kilpatrick Townsend & Stockton

LLP regarding intellectual property matters, dated as of such date in form and substance satisfactory to the Representative.

(e) Opinion of Counsel for the Underwriters. On the Closing Date and each Option Closing Date the Representative shall have received the opinion of McDermott Will & Emery, LLP, counsel for the Underwriters in connection with the offer and sale of the Securities, in form and substance satisfactory to the Representative, dated as of such date.

(f) Officers’ Certificate. On the Closing Date and each Option Closing Date the Representative shall have received a certificate executed by the President and Chief Executive Officer of the Company, dated as of such date, to the effect set forth in Section 6(b)(ii) and further to the effect that:

(i) for the period from and including the date of this Agreement through and including such date, there has not occurred any Material Adverse Effect;

(ii) the representations, warranties and covenants of the Company set forth in Section 1 of this Agreement are true and correct with the same force and effect as though expressly made on and as of such date; and

(iii) the Company has complied with all the agreements hereunder and satisfied all the conditions on its part to be performed or satisfied hereunder at or prior to such date.

(g) Principal Accounting Officer’s Certificate . On the Closing Date and each Option Closing Date, the Representative shall have received a certificate executed by the Principal Accounting Officer of the Company, dated as of such date, in form and substance satisfactory to the Representative, dated as of such date.

(h) Bring-down Comfort Letters . (i) On each Option Closing Date the Representative shall have received from KPMG LLP, independent registered public accountants for the Company, a letter dated such date, in form and substance satisfactory to the Representative, which letter shall: (a) reaffirm the statements made in the letter furnished by them pursuant to Section 6(a), except that the specified date referred to therein for the carrying out of procedures shall be no more than three business days prior to the applicable Option Closing Date, as the case may be; and (b) cover certain financial information contained in the Prospectus.

(i) Lock-Up Agreements. On or prior to the date hereof, the Company shall have furnished to the Representative an agreement in the form of Exhibit A hereto from each of the Company’s directors and officers (as defined in Rule 16a-1(f) under the Exchange Act) and the Company’s principal stockholder, and each such agreement shall be in full force and effect on each of the First Closing Date and each Option Closing Date.

(j) Rule 462(b) Registration Statement. In the event that a Rule 462(b) Registration Statement is filed in connection with the offering contemplated by this Agreement, such Rule 462(b) Registration Statement shall have been filed with the Commission on the date of this Agreement and shall have become effective automatically upon such filing.

(k) Nasdaq Listing. The Company shall have submitted a listing of additional shares notification form to Nasdaq with respect to the Shares and Warrant Shares and shall have received no objection thereto from Nasdaq and shall have received a conditional listing approval that is subject only to customary listing conditions.

(l) Pre-Funded Warrants . The Company shall have delivered executed copies of the Pre-Funded Warrants to the public purchasers thereof.

(m) Common Warrants . The Company shall have delivered executed copies of the Common Warrants to the public purchasers thereof.

(n) Option Warrants . The Company shall have delivered executed copies of the Option Warrants to the public purchasers thereof.

(o) Representative Warrants . The Company shall have delivered executed copies of the Representative Warrants to the Representative related to the Closing Date and/or Option Closing Date, as applicable.

(p) Additional Documents. On or before the Closing Date and each Option Closing Date, the Representative and counsel for the Underwriters shall have received such information, documents and opinions as they may reasonably request for the purposes of enabling them to pass upon the issuance and sale of the Securities as contemplated herein, or in order to evidence the accuracy of any of the representations and warranties, or the satisfaction of any of the conditions or agreements, herein contained; and all proceedings taken by the Company in connection with the issuance and sale of the Securities as contemplated herein and in connection with the other transactions contemplated by this Agreement shall be satisfactory in form and substance to the Representative and counsel for the Underwriters.

If any condition specified in this Section 6 is not satisfied when and as required to be satisfied, this Agreement may be terminated by the Representative by notice from the Representative to the Company at any time on or prior to the Closing Date and, with respect to the Securities, at any time on or prior to the applicable Option Closing Date, which termination shall be without liability on the part of any party to any other party, except that Section 4, Section 7, Section 9 and Section 10 shall at all times be effective and shall survive such termination.

7. Reimbursement of Underwriters’ Expenses . If this Agreement is terminated for any reason, the Company agrees to reimburse the Representative and the other Underwriters (or such Underwriters as have terminated this Agreement with respect to themselves), severally, upon demand for all out-of-pocket expenses that shall have been reasonably incurred by the Representative and the Underwriters in connection with the proposed purchase and the offering and sale of the Securities, including, but not limited to, fees and disbursements of counsel, printing expenses, travel expenses, postage, facsimile and telephone charges; provided that such out-of-pocket expenses shall not exceed $40,000.

8. Effectiveness of this Agreement . This Agreement shall become effective upon the execution and delivery hereof by the parties hereto.

9. Indemnification.

(a) Indemnification of the Underwriters. The Company shall indemnify and hold harmless each Underwriter, its affiliates, the directors, officers, employees, counsel and agents of each Underwriter and each person, if any, who controls each Underwriter within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act from and against any and all losses, claims, liabilities, expenses and damages (including any and all investigative, legal and other expenses reasonably incurred in connection with, and any amount paid in settlement of, any action, suit or proceeding between any of the indemnified parties and any indemnifying parties or between any indemnified party and any third party, or otherwise, or any claim asserted), to which they, or any of them, may become subject under the Securities Act, the Exchange Act or other Federal or state statutory law or regulation, at common law or otherwise, insofar as such losses, claims, liabilities, expenses or damages arise out of or are based on (i) any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement (or any amendment thereto), including any information deemed to be a part thereof pursuant to Rules 430A, 430B or 430C, as applicable or the omission or alleged omission therefrom of a material fact required to be stated therein or necessary to make the statements therein not misleading or (ii) any untrue statement or alleged untrue statement of a material fact contained in any preliminary prospectus, any free writing prospectus, the Pricing Disclosure Package or the Prospectus (or any amendment or supplement to any of the foregoing) or the omission or alleged omission therefrom of a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading or (iii) any untrue statement or alleged untrue statement of a material fact contained in any materials or information provided to investors by, or with the approval of, the Company in connection with the marketing of the offering of the Securities, including any roadshow or investor presentations made to investors by the Company (whether in person or electronically) or the omission or alleged omission therefrom of a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided , however , that the Company shall not be liable to the extent that such loss, claim, liability, expense or damage arises from the sale of the Securities in the public offering to any person by an Underwriter and is based on an untrue statement or omission or alleged untrue statement or omission made in reliance on and in conformity with Underwriter Information. This indemnity agreement will be in addition to any liability that the Company might otherwise have.

(b) Indemnification of the Company . Each Underwriter shall indemnify and hold harmless the Company, its affiliates, the directors, officers, employees, counsel and agents, each person, if any, who controls the Company within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act to the same extent as the foregoing indemnity from the Company to each Underwriter, but only insofar as losses, claims, liabilities, expenses or damages arise out of or are based on any untrue statement or omission or alleged untrue statement or omission made in reliance on and in conformity with Underwriter Information. This indemnity will be in addition to any liability that each Underwriter might otherwise have. The Company hereby acknowledges that the only information that the Underwriters have furnished to the Company expressly for use in the Registration Statement, any preliminary prospectus, any free writing prospectus, the Pricing Disclosure Package or the Prospectus (or any amendment or supplement to any of the foregoing) are the statements set forth in the fifth, tenth, sixteenth, seventeenth and eighteenth paragraphs under the caption “Underwriting” in the Preliminary Prospectus and Prospectus (the “ Underwriter Information ”).

(c) Notifications and Other Indemnification Procedures . Any party that proposes to assert the right to be indemnified under this Section 9 shall, promptly after receipt of notice of commencement of any action against such party in respect of which a claim is to be made against an indemnifying party or parties under this Section 9, notify each such indemnifying party of the commencement of such action, enclosing a copy of all papers served, but the omission so to notify such indemnifying party shall not relieve the indemnifying party from any liability that it may have to any indemnified party under the foregoing provisions of this Section 9 unless, and only to the extent that, such omission results in the forfeiture of substantive rights or defenses by the indemnifying party. If any such action is brought against any indemnified party and it notifies the indemnifying party of its commencement, the indemnifying party will be entitled to participate in and, to the extent that it elects by delivering written notice to the indemnified party promptly after receiving notice of the commencement of the action from the indemnified party, jointly with any other indemnifying party similarly notified, to assume the defense of the action, with its own counsel, and after notice from the indemnifying party to the indemnified party of its election to assume the defense, the indemnifying party will not be liable to the indemnified party for any legal or other expenses except as provided below and except for the reasonable costs of investigation subsequently incurred by the indemnified party in connection with the defense. The indemnified party will have the right to employ its own counsel (including local counsel, if necessary) in any such action, but the fees, expenses and other charges of such counsel will be at the expense of such indemnified party unless (i) the employment of counsel by the indemnified party has been authorized in writing by the indemnifying party, (ii) the indemnified party has reasonably concluded (based on advice of counsel) that there may be legal defenses available to it or other indemnified parties that are different from or in addition to those available to the indemnifying party, (iii) the indemnified party has reasonably concluded that a conflict or potential conflict exists (based on advice of counsel to the indemnified party) between the indemnified party and the indemnifying party (in which case the indemnifying party shall not have the right to direct the defense of such action on behalf of the indemnified party) or (iv) the indemnifying party has not in fact employed counsel reasonably satisfactory to the indemnified party to assume the defense of such action within a reasonable time after receiving notice of the commencement of the action, in each of which cases the reasonable fees, disbursements and other charges of counsel shall be at the expense of the indemnifying party or parties. It is understood that the indemnifying party or parties shall not, in connection with any proceeding or related proceedings in the same jurisdiction, be liable for the reasonable fees, disbursements and other charges of more than one separate firm admitted to practice in such jurisdiction at any one time for all such indemnified party or parties. All such fees, disbursements and other charges shall be reimbursed by the indemnifying party promptly as they are incurred. An indemnifying party shall not be liable for any settlement of any action or claim effected without its written consent (which consent will not be unreasonably withheld or delayed). No indemnifying party shall, without the prior written consent of each indemnified party, settle or compromise or consent to the entry of any judgment in any pending or threatened claim, action or proceeding relating to the matters contemplated by this Section 9 (whether or not any indemnified party is a party thereto), unless such settlement, compromise or consent (i) includes an unconditional release of each indemnified party from all liability arising or that may arise out of such claim, action or proceeding and (ii) does not include a statement as to or an admission of fault, culpability or a failure to act by or on behalf of any indemnified party. Notwithstanding the foregoing, if at any time an indemnified party shall have requested an indemnifying party to reimburse the indemnified party for fees and expenses of counsel, such indemnifying party agrees that it shall be liable for any settlement of the nature contemplated by

Section 9(a) effected without its written consent if (i) such settlement is entered into more than 45 days after receipt by such indemnifying party of the aforesaid request, (ii) such indemnifying party shall have received notice of the terms of such settlement at least 30 days prior to such settlement being entered into and (iii) such indemnifying party shall not have reimbursed such indemnified party in accordance with such request prior to the date of such settlement.

10. Contribution . In order to provide for just and equitable contribution in circumstances in which the indemnification provided for in the foregoing paragraphs of Section 9 is applicable in accordance with its terms but for any reason is held to be unavailable from the Company or the Underwriters, the Company and the Underwriters shall contribute to the total losses, claims, liabilities, expenses and damages (including any investigative, legal and other expenses reasonably incurred in connection with, and any amount paid in settlement of, any action, suit or proceeding or any claim asserted, but after deducting any contribution received by the Company from persons other than the Underwriters, such as persons who control the Company within the meaning of the Securities Act, officers of the Company who signed the Registration Statement and directors of the Company, who also may be liable for contribution) to which the Company and the Underwriters may be subject in such proportion as shall be appropriate to reflect the relative benefits received by the Company on the one hand and the Underwriters on the other. The relative benefits received by the Company on the one hand and the Underwriters on the other shall be deemed to be in the same proportion as the total net proceeds from the offering (before deducting expenses) received by the Company bear to the total underwriting discounts and commissions received by the Underwriters, in each case as set forth in the table on the cover page of the Prospectus. If, but only if, the allocation provided by the foregoing sentence is not permitted by applicable law, the allocation of contribution shall be made in such proportion as is appropriate to reflect not only the relative benefits referred to in the foregoing sentence but also the relative fault of the Company, on the one hand, and the Underwriters, on the other, with respect to the statements or omissions which resulted in such loss, claim, liability, expense or damage, or action in respect thereof, as well as any other relevant equitable considerations with respect to such offering. Such relative fault shall be determined by reference to whether the untrue or alleged untrue statement of a material fact or omission or alleged omission to state a material fact relates to information supplied by the Company or Representatives on behalf of the Underwriters, the intent of the parties and their relative knowledge, access to information and opportunity to correct or prevent such statement or omission. The Company and the Underwriters agree that it would not be just and equitable if contributions pursuant to this Section 10 were to be determined by pro rata allocation or by any other method of allocation (even if the Underwriters were treated as one entity for such purpose) which does not take into account the equitable considerations referred to herein. The amount paid or payable by an indemnified party as a result of the loss, claim, liability, expense or damage, or action in respect thereof, referred to above in this Section 10 shall be deemed to include, for purpose of this Section 10, any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending any such action or claim. Notwithstanding the provisions of this Section 10, no Underwriter shall be required to contribute any amount in excess of the underwriting discounts and commissions received by it, and no person found guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligation to contribute as provided in this Section 10 are several in proportion to their respective underwriting obligations and not joint. For purposes of this Section 10, any person who controls a party to this Agreement within the meaning of the

Securities Act will have the same rights to contribution as that party, and each officer of the Company who signed the Registration Statement will have the same rights to contribution as the Company, and each director, officer, employee, counsel or agent of any Underwriter will have the same rights to contribution as such Underwriter, subject in each case to the provisions hereof. Any party entitled to contribution, promptly after receipt of notice of commencement of any action against such party in respect of which a claim for contribution may be made under this Section 10, will notify any such party or parties from whom contribution may be sought, but the omission so to notify will not relieve the party or parties from whom contribution may be sought from any other obligation it or they may have under this Section 10. No party will be liable for contribution with respect to any action or claim settled without its written consent (which consent will not be unreasonably withheld).

11. Default of One or More of the Several Underwriters. If, on the Closing Date or any Option Closing Date any one or more of the several Underwriters shall fail or refuse to purchase the Firm Securities or Option Securities, as applicable, that it or they have agreed to purchase hereunder on such date, and the aggregate number of Firm Securities or Option Securities which such defaulting Underwriter or Underwriters agreed but failed or refused to purchase does not exceed 10% of the aggregate number of the Firm Securities or Option Securities, as applicable, to be purchased on such date, the Representative may make arrangements satisfactory to the Company for the purchase of such Firm Securities or Option Securities, as applicable, by other persons, including any of the Underwriters, but if no such arrangements are made by such date, the other Underwriters shall be obligated, severally and not jointly, in the proportions that the number of Firm Securities and Option Securities set forth opposite their respective names on Schedule A bears to the aggregate number of Firm Securities and Option Securities set forth opposite the names of all such non-defaulting Underwriters, or in such other proportions as may be specified by the Representative with the consent of the non-defaulting Underwriters, to purchase the Firm Securities and Option Securities which such defaulting Underwriter or Underwriters agreed but failed or refused to purchase on such date. If, on the Closing Date or any Option Closing Date any one or more of the Underwriters shall fail or refuse to purchase Firm Securities or Option Securities and the aggregate number of Firm Securities and Option Securities with respect to which such default occurs exceeds 10% of the aggregate number of Firm Securities or Option Securities to be purchased on such date, and arrangements satisfactory to the Representative and the Company for the purchase of such Firm Securities and Option Securities are not made within 48 hours after such default, this Agreement shall terminate without liability of any party to any other party except that the provisions of Section 4, Section 7, Section 9 and Section 10 shall at all times be effective and shall survive such termination. In any such case either the Representative or the Company shall have the right to postpone the Closing Date or the applicable Option Closing Date, as the case may be, but in no event for longer than seven days in order that the required changes, if any, to the Registration Statement and the Prospectus or any other documents or arrangements may be effected.

As used in this Agreement, the term “ Underwriter ” shall be deemed to include any person substituted for a defaulting Underwriter under this Section 11. Any action taken under this Section 11 shall not relieve any defaulting Underwriter from liability in respect of any default of such Underwriter under this Agreement.

12. Termination of this Agreement. Prior to the purchase of the Firm Securities by the Underwriters on the Closing Date, this Agreement may be terminated by the Representative by notice given to the Company if at any time: (i) trading or quotation in any of the Company’s securities shall have been suspended or limited by the Commission, any other securities regulatory authority, or by Nasdaq or trading in securities generally on the NYSE or Nasdaq shall have been suspended or limited, or minimum or maximum prices shall have been generally established on any of such stock exchanges; (ii) a general banking moratorium shall have been declared by any of U.S. federal or New York or authorities or a major disruption of securities settlements or clearing services in the United States shall have occurred and be continuing; (iii) there shall have occurred any outbreak or escalation of national or international hostilities or any crisis or calamity, or any substantial change in the United States or international financial markets, or any substantial change or development involving a prospective substantial change in United States’ or international political, financial or economic conditions, as in the judgment of the Representative is material and adverse and makes it impracticable to market the Securities in the manner and on the terms described in the Pricing Disclosure Package or the Prospectus or to enforce contracts for the sale of securities; (iv) in the good faith judgment of the Representative there shall have occurred any material adverse change, or any development or event involving a prospective material adverse change, in the condition, financial or otherwise, or in the business, properties, earnings, results of operations or prospects of the Company and its Subsidiaries considered as one enterprise, whether or not arising in the ordinary course of business; or (v) the Company shall have sustained a loss by strike, fire, flood, earthquake, accident or other calamity of such character as in the judgment of the Representative may interfere materially with the conduct of the business and operations of the Company regardless of whether or not such loss shall have been insured. Any termination pursuant to this Section 12 shall be without liability on the part of (a) the Company to any Underwriter, except that the Company shall be obligated to reimburse the expenses of the Representative and the Underwriters pursuant to Section 4 and Section 7 hereof or (b) any Underwriter to the Company; provided, however, that the provisions of Section 9, Section 10, and Section 12 shall at all times be effective and shall survive such termination.

If this Agreement is terminated prior to the purchase of the Firm Securities by the Underwriters on the Closing, and the Company consummates a public or private offering or other financing or capital-raising transaction of any kind (“Tail Financing”) by investors whom Representative had contacted on or before the date hereof or introduced to the Company on or before the date hereof, then Representative shall be entitled to receive with respect to each Tail Financing (i) a cash fee, or as to an underwritten public offering a discount, equal to 7.0% of the aggregate gross proceeds raised in the Tail Financing, and (ii) warrants to purchase that number of shares of Common Stock of the Company equal to 7.0% of the aggregate number of shares of Common Stock issued and sold in the public or private offering that constitutes the Tail Financing, issuable to the Representative or its designees, with such warrants having the same terms as the warrants issued to investors in such underwritten public offering, except that the exercise price shall equal to 125% of the public offering price.

13. No Advisory or Fiduciary Relationship. The Company acknowledges and agrees that (i) the purchase and sale of the Securities pursuant to this Agreement, including the determination of the public offering price of the Securities and any related discounts and commissions, is an arm’s-length commercial transaction between the Company, on the one hand, and the several Underwriters, on the other hand, (ii) in connection with the offering contemplated

hereby and the process leading to such transaction, each Underwriter is and has been acting solely as a principal and is not the agent or fiduciary of the Company, or its stockholders, or its creditors, employees or any other party, (iii) no Underwriter has assumed or will assume an advisory or fiduciary responsibility in favor of the Company with respect to the offering contemplated hereby or the process leading thereto (irrespective of whether such Underwriter has advised or is currently advising the Company on other matters) and no Underwriter has any obligation to the Company with respect to the offering contemplated hereby except the obligations expressly set forth in this Agreement, (iv) the Underwriters and their respective affiliates may be engaged in a broad range of transactions that involve interests that differ from those of the Company, and (v) the Underwriters have not provided any legal, accounting, regulatory or tax advice with respect to the offering contemplated hereby and the Company has consulted its own legal, accounting, regulatory and tax advisors to the extent it deemed appropriate.

14. Representations and Agreements to Survive Delivery. The respective indemnities, agreements, representations, warranties and other statements of the Company, of its officers and of the several Underwriters set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any investigation made by or on behalf of any Underwriter or the Company or any of its or their partners, officers, directors or employees or any controlling person, as the case may be, and, anything herein to the contrary notwithstanding, will survive delivery of and payment for the Securities sold hereunder and any termination of this Agreement.

15. Notices . All communications hereunder shall be in writing and shall be mailed, hand delivered or telecopied and confirmed to the parties hereto as follows:

If to the Representative: H.C. Wainwright & Co., LLC

430 Park Avenue, 4 th Floor

New York, NY 10022

Facsimile: (212) 214-0803

Attention: Head of Investment Banking

with a copy to: McDermott Will & Emery LLP

340 Madison Ave

New York, NY 10173

Attention: Gary Emmanuel

If to the Company: Vaxart, Inc.

290 Utah Ave. Suite 200

South San Francisco, California 94080

Attention: Chief Executive Officer

with a copy to: Cooley LLP

3175 Hanover Street

Palo Alto, CA 94304

Attention: John T. McKenna

Josh Seidenfeld

Each party to this Agreement may change such address for notices by sending to the parties to this Agreement written notice of a new address for such purpose. Each such notice or other communication shall be deemed given (i) when delivered personally or by verifiable facsimile transmission (with an original to follow) on or before 4:30 p.m., New York City time, on a Business Day or, if such day is not a Business Day, on the next succeeding Business Day, (ii) on the next Business Day after timely delivery to a nationally-recognized overnight courier and (iii) on the Business Day actually received if deposited in the U.S. mail (certified or registered mail, return receipt requested, postage prepaid). For purposes of this Agreement, “ Business Day ” shall mean any day on which the Exchange and commercial banks in the City of New York are open for business.

16. An electronic communication (“ Electronic Notice ”) shall be deemed written notice for purposes of this Section 16 if sent to the electronic mail address specified by the receiving party under separate cover. Electronic Notice shall be deemed received at the time the party sending Electronic Notice receives verification of receipt by the receiving party. Any party receiving Electronic Notice may request and shall be entitled to receive the notice on paper, in a nonelectronic form (“ Nonelectronic Notice ”) which shall be sent to the requesting party within ten (10) days of receipt of the written request for Nonelectronic Notice.

17. Successors and Assigns. This Agreement shall inure to the benefit of and be binding upon the Company and the Underwriters and their respective successors and the parties referred to in Section 9 hereof. References to any of the parties contained in this Agreement shall be deemed to include the successors and permitted assigns of such party. Nothing in this Agreement, express or implied, is intended to confer upon any party other than the parties hereto or their respective successors and permitted assigns any rights, remedies, obligations or liabilities under or by reason of this Agreement, except as expressly provided in this Agreement. Neither party may assign its rights or obligations under this Agreement without the prior written consent of the other party; provided, however, that the Underwriter may assign its rights and obligations hereunder to an affiliate thereof without obtaining the Company’s consent.

18. Partial Unenforceability. The invalidity or unenforceability of any section, paragraph or provision of this Agreement shall not affect the validity or enforceability of any other section, paragraph or provision hereof. If any section, paragraph or provision of this Agreement is for any reason determined to be invalid or unenforceable, there shall be deemed to be made such minor changes (and only such minor changes) as are necessary to make it valid and enforceable.

19. Entire Agreement; Amendment; Severability; Waiver . This Agreement (including all schedules and exhibits attached hereto issued pursuant hereto) constitutes the entire agreement and supersedes all other prior and contemporaneous agreements and undertakings, both written and oral, among the parties hereto with regard to the subject matter hereof, including, for the avoidance of doubt, that certain engagement letter, dated as of January 25, 2019, as amended, by and between the Company and H.C. Wainwright & Co., LLC. Neither this Agreement nor any term hereof may be amended except pursuant to a written instrument executed by the Company and the Underwriters. In the event that any one or more of the provisions contained herein, or the application thereof in any circumstance, is held invalid, illegal or unenforceable as written by a court of competent jurisdiction, then such provision shall be given full force and effect to the fullest possible extent that it is valid, legal and enforceable, and the remainder of the terms and provisions

herein shall be construed as if such invalid, illegal or unenforceable term or provision was not contained herein, but only to the extent that giving effect to such provision and the remainder of the terms and provisions hereof shall be in accordance with the intent of the parties as reflected in this Agreement. No implied waiver by a party shall arise in the absence of a waiver in writing signed by such party. No failure or delay in exercising any right, power, or privilege hereunder shall operate as a waiver thereof, nor shall any single or partial exercise thereof preclude any other or further exercise thereof or the exercise of any right, power, or privilege hereunder.

20. GOVERNING LAW AND TIME; WAIVER OF JURY TRIAL . THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO THE PRINCIPLES OF CONFLICTS OF LAWS. SPECIFIED TIMES OF DAY REFER TO NEW YORK CITY TIME. EACH PARTY HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATING TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY.

21. CONSENT TO JURISDICTION . EACH PARTY HEREBY IRREVOCABLY SUBMITS TO THE EXCLUSIVE JURISDICTION OF THE STATE AND FEDERAL COURTS SITTING IN THE CITY OF NEW YORK, BOROUGH OF MANHATTAN, FOR THE ADJUDICATION OF ANY DISPUTE HEREUNDER OR IN CONNECTION WITH ANY TRANSACTION CONTEMPLATED HEREBY, AND HEREBY IRREVOCABLY WAIVES, AND AGREES NOT TO ASSERT IN ANY SUIT, ACTION OR PROCEEDING, ANY CLAIM THAT IT IS NOT PERSONALLY SUBJECT TO THE JURISDICTION OF ANY SUCH COURT, THAT SUCH SUIT, ACTION OR PROCEEDING IS BROUGHT IN AN INCONVENIENT FORUM OR THAT THE VENUE OF SUCH SUIT, ACTION OR PROCEEDING IS IMPROPER. EACH PARTY HEREBY IRREVOCABLY WAIVES PERSONAL SERVICE OF PROCESS AND CONSENTS TO PROCESS BEING SERVED IN ANY SUCH SUIT, ACTION OR PROCEEDING BY MAILING A COPY THEREOF (CERTIFIED OR REGISTERED MAIL, RETURN RECEIPT REQUESTED) TO SUCH PARTY AT THE ADDRESS IN EFFECT FOR NOTICES TO IT UNDER THIS AGREEMENT AND AGREES THAT SUCH SERVICE SHALL CONSTITUTE GOOD AND SUFFICIENT SERVICE OF PROCESS AND NOTICE THEREOF. NOTHING CONTAINED HEREIN SHALL BE DEEMED TO LIMIT IN ANY WAY ANY RIGHT TO SERVE PROCESS IN ANY MANNER PERMITTED BY LAW.

22. Counterparts . This Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument. Delivery of an executed Agreement by one party to the other may be made by facsimile or electronic transmission.

23. Construction .

(a) the section and exhibit headings herein are for convenience only and shall not affect the construction hereof;

(b) words defined in the singular shall have a comparable meaning when used in the plural, and vice versa;

(c) the words “hereof,” “hereto,” “herein” and “hereunder” and words of similar import, when used in this Agreement, shall refer to this Agreement as a whole and not to any particular provision of this Agreement;

(d) wherever the word “include,” “includes” or “including” is used in this Agreement, it shall be deemed to be followed by the words “without limitation”;

(e) references herein to any gender shall include each other gender;

(f) references herein to any law, statute, ordinance, code, regulation, rule or other requirement of any Governmental Authority shall be deemed to refer to such law, statute, ordinance, code, regulation, rule or other requirement of any Governmental Authority as amended, reenacted, supplemented or superseded in whole or in part and in effect from time to time and also to all rules, policies, notices, instruments and regulations promulgated thereunder;

(g) if the last day for the giving of any notice or the performance of any act required or permitted under this Agreement is a day that is not a Business Day, then the time for the giving of such notice or the performance of such action shall be extended to the next succeeding Business Day; and

(h) “ knowledge ” means, as it pertains to the Company, the actual knowledge of the officers and directors of the Company, together with the knowledge which they would have had if they had conducted a reasonable inquiry of the relevant persons into the relevant subject matter.

(i) “ Governmental Authority ” means (i) any federal, state, local, municipal, national or international government or governmental authority, regulatory or administrative agency, governmental commission, department, board, bureau, agency or instrumentality, court, tribunal, arbitrator or arbitral body (public or private); (ii) any self-regulatory organization (including any stock exchange or quotation system); or (iii) any political subdivision of any of the foregoing.

24. General Provisions.

Each of the parties hereto acknowledges that it is a sophisticated business person who was adequately represented by counsel during negotiations regarding the provisions hereof, including, without limitation, the indemnification provisions of Section 9 and the contribution provisions of Section 10, and is fully informed regarding said provisions. Each of the parties hereto further acknowledges that the provisions of Section 9 and Section 10 hereof fairly allocate the risks in light of the ability of the parties to investigate the Company, its affairs and its business in order to assure that adequate disclosure has been made in the Registration Statement, any preliminary prospectus, the Pricing Disclosure Package, each free writing prospectus and the Prospectus (and any amendments and supplements to the foregoing), as contemplated by the Securities Act and the Exchange Act.

[ Signature Page Follows ]

If the foregoing correctly sets forth the understanding between the Company and the Underwriters, please so indicate in the space provided below for that purpose, whereupon this letter shall constitute a binding agreement between the Company and the Underwriters.

	Very truly yours,

	VAXART, INC.


	By:
		Name: Wouter W. Latour, M.D.
		Title: President and Chief Executive Officer


	ACCEPTED as of the date first-above written:


	H.C. WAINWRIGHT & CO., LLC

	On behalf of itself and the several Underwriters named in Schedule A hereto.

	By:
		Name:
		Title:

SIGNATURE PAGE

UNDERWRITING AGREEMENT

Schedule A

Underwriters

Firm Shares

Pre-Funded
Warrants

Common
Warrants

Option
Shares

Option
Warrants

Aggregate Purchase
Price

H.C. Wainwright & Co., LLC

[ · ]

CIM Securities, LLC

[ · ]

Total

[ · ]

Schedule B

Free Writing Prospectuses Included in the Pricing Disclosure Package

None.

Schedule C

Pricing Information

Number of Firm Shares: [ · ]

Number of Pre-Funded Warrants: [ · ]

Number of Common Warrants: [ · ]

Number of Option Shares: [ · ]

Number of Option Warrants: [ · ]

Public Offering Price per Share: $[ · ]

Public Offering Price per Pre-Funded Warrant: $[ · ]

Public Offering Price per Common Warrant:$[ · ]

Public Offering Price per Option Warrant:$[ · ]

Pre-Funded Warrant Exercise Price: $0.01

Common Warrant Exercise Price:$[ · ]

Option Warrant Exercise Price:$[ · ]

Underwriting Discount per Share: $[ · ]

Underwriting Discount per Pre-Funded Warrant: $[ · ]

Underwriting Discount per Common Warrant: $[ · ]

Underwriting Discount per Option Warrant: $[ · ]

Proceeds to Company per Share (before expenses): $[ · ]

Proceeds to Company per Common Warrant (before expenses): $[ · ]

Proceeds to Company per Option Warrant (before expenses): $[ · ]

Proceeds to Company per Pre-Funded Warrant (before expenses): $[ · ]

Schedule D

Subsidiaries

Vaxart Biosciences, Inc.

Biota Holdings Pty, Ltd.

Biota Scientific Management Pty, Ltd.

Biota Europe Limited

Anaconda Pharma, S.A.S.

Exhibit A

Form of Lock-up Agreement

Exhibit A

Lock-Up Agreement

February , 2019

H.C. WAINWRIGHT & CO. LLC

As Representative of the several Underwriters

c/o H.C. Wainwright & Co. LLC

430 Park Avenue

New York, New York 10022

Re: Vaxart, Inc.

Ladies and Gentlemen:

This Lock-Up Agreement (this “Agreement”) is being delivered to you in connection with the proposed Underwriting Agreement (the “Underwriting Agreement”) between Vaxart, Inc., a Delaware corporation (the “Company”), and H.C. Wainwright & Co. LLC (“Wainwright”), as representative of a group of underwriters (collectively, the “Underwriters”), to be named therein, and the other parties thereto (if any), relating to the proposed public offering of shares of the common stock, par value $0.10 per share (the “Common Stock”) and warrants to purchase Common Stock, of the Company (collectively, the “Securities” and the “Offering”).

In order to induce you and the other Underwriters to enter into the Underwriting Agreement, and in light of the benefits that the Offering of the Securities will confer upon the undersigned in its capacity as a securityholder and/or an officer, director or employee of the Company, and for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the undersigned agrees with each Underwriter that, during the period beginning on the date hereof through and including the date that is the 90 th day after the date of the Underwriting Agreement (the “Lock-Up Period”), the undersigned will not, without the prior written consent of Wainwright, directly or indirectly, (i) offer, sell, assign, transfer, pledge, contract to sell, or otherwise dispose of, or announce the intention to otherwise dispose of, any shares of Common Stock whether now owned or hereafter acquired by the undersigned (including, without limitation, Common Stock which may be deemed to be beneficially owned by the undersigned in accordance with the rules and regulations promulgated under the Securities Act of 1933, as the same may be amended or supplemented from time to time (such shares, the “Beneficially Owned Shares”)) or securities convertible into or exercisable or exchangeable for Common Stock, (ii) enter into any swap, hedge or similar agreement or arrangement that transfers in whole or in part, the economic risk of ownership of the Beneficially Owned Shares or securities convertible into or exercisable or exchangeable for Common Stock, whether now owned or hereafter acquired by the undersigned or with respect to which the undersigned has or hereafter acquires the power of disposition, or (iii) engage in any short selling of the Common Stock or securities convertible into or exercisable or exchangeable for Common Stock.

The restrictions set forth in the immediately preceding paragraph shall not apply to :

(1) shares of Common Stock acquired in open market transactions after the closing of the Offering,

(2) if the undersigned is a natural person, any transfers made by the undersigned (a) as a bona fide gift to any member of the immediate family (as defined below) of the undersigned or to a trust the beneficiaries of which are exclusively the undersigned or members of the undersigned’s immediate family, (b) by will or intestate succession upon the death of the undersigned or (c) as a bona fide gift to a charity or educational institution,

(3) if the undersigned is a corporation, partnership, limited liability company or other business entity, any transfers to any shareholder, partner or member of, or owner of a similar equity interest in, the undersigned, as the case may be, if, in any such case, such transfer is not for value, and

(4) if the undersigned is a corporation, partnership, limited liability company or other business entity, any transfer made by the undersigned (a) in connection with the sale or other bona fide transfer in a single transaction of all or substantially all of the undersigned’s capital stock, partnership interests, membership interests or other similar equity interests, as the case may be, or all or substantially all of the undersigned’s assets, in any such case not undertaken for the purpose of

avoiding the restrictions imposed by this Agreement or (b) to another corporation, partnership, limited liability company or other business entity so long as the transferee is an affiliate (as defined below) of the undersigned and such transfer is not for value;

provided, however , that in the case of any transfer described in clause (2), (3) or (4) above, it shall be a condition to the transfer that (A) the transferee executes and delivers to Wainwright, acting on behalf of the Underwriters, not later than one business day prior to such transfer, a written agreement, in substantially the form of this Agreement (it being understood that any references to “immediate family” in the agreement executed by such transferee shall expressly refer only to the immediate family of the undersigned and not to the immediate family of the transferee) and otherwise satisfactory in form and substance to Wainwright, and (B) if the undersigned is required to file a report under Section 16(a) of the Securities Exchange Act of 1934, as amended, reporting a reduction in beneficial ownership of shares of Common Stock or Beneficially Owned Shares or any securities convertible into or exercisable or exchangeable for Common Stock or Beneficially Owned Shares during the Lock-Up Period (as the same may be extended as described above), the undersigned shall include a statement in such report to the effect that, in the case of any transfer pursuant to clause (2) above, such transfer is being made as a gift or by will or intestate succession or, in the case of any transfer pursuant to clause (3) above, such transfer is being made to a shareholder, partner or member of, or owner of a similar equity interest in, the undersigned and is not a transfer for value or, in the case of any transfer pursuant to clause (4) above, such transfer is being made either (a) in connection with the sale or other bona fide transfer in a single transaction of all or substantially all of the undersigned’s capital stock, partnership interests, membership interests or other similar equity interests, as the case may be, or all or substantially all of the undersigned’s assets or (b) to another corporation, partnership, limited liability company or other business entity that is an affiliate of the undersigned and such transfer is not for value. For purposes of this paragraph, “immediate family” shall mean a spouse, child, grandchild or other lineal descendant (including by adoption), father, mother, brother or sister of the undersigned; and “affiliate” shall have the meaning set forth in Rule 405 under the Securities Act of 1933, as amended.

The undersigned further agrees that (i) it will not, during the Lock-Up Period (as the same may be extended as described above), make any demand or request for or exercise any right with respect to the registration under the Securities Act of 1933, as amended, of any shares of Common Stock or other Beneficially Owned Shares or any securities convertible into or exercisable or exchangeable for Common Stock or other Beneficially Owned Shares, and (ii) the Company may, with respect to any Common Stock or other Beneficially Owned Shares or any securities convertible into or exercisable or exchangeable for Common Stock or other Beneficially Owned Shares owned or held (of record or beneficially) by the undersigned, cause the transfer agent or other registrar to enter stop transfer instructions and implement stop transfer procedures with respect to such securities during the Lock-Up Period (as the same may be extended as described above). In addition, the undersigned hereby waives, from the date hereof until the expiration of the 90-day period following the date of the Underwriting Agreement and any extension of such period pursuant to the terms hereof, any and all rights, if any, to request or demand registration pursuant to the Securities Act of 1933, as amended, of any shares of Common Stock that are registered in the name of the undersigned or that are Beneficially Owned Shares.

The undersigned hereby represents and warrants that the undersigned has full power and authority to enter into this Agreement and that this Agreement has been duly authorized (if the undersigned is not a natural person), executed and delivered by the undersigned and is a valid and binding agreement of the undersigned. This Agreement and all authority herein conferred are irrevocable and shall survive the death or incapacity of the undersigned (if a natural person) and shall be binding upon the heirs, personal representatives, successors and assigns of the undersigned. This Agreement shall be governed by, and construed in accordance with, the laws of the State of New York.

If (i) the Company notifies Wainwright in writing that it does not intend to proceed with the Offering, (ii) the Underwriting Agreement is not executed before April 15, 2019 or (iii) the Underwriting Agreement (other than the provisions thereof that survive termination) terminates or is terminated prior to payment for and delivery of the Securities to be sold thereunder, then in each case, this Agreement shall automatically, and without any action on the part of any other party, terminate and be of no further force and effect, and the undersigned shall automatically be released from the obligations under this Agreement.

[Remainder of page intentionally left blank.]

The undersigned acknowledges and agrees that whether or not any public offering of the Securities actually occurs depends on a number of factors, including market conditions.

	Very truly yours,


	(Name of Stockholder - Please Print)


	(Signature)


	(Name of Signatory if Stockholder is an entity - Please Print)


	(Title of Signatory if Stockholder is an entity - Please Print)

	Address:

Exhibit B

Directors and Executive Officers and Principal Stockholder Signing Lock-up Agreement

1. Anne Vanlent

2. Geoffrey Cox

3. John Richard

4. Michael Finney

5. Richard Markham

6. Sean Tucker

7. Wouter Latour

8. Care Capital

Exhibit 4.4

COMMON STOCK PURCHASE WARRANT

VAXART, INC.

Warrant Shares:		Initial Exercise Date: , 2019
		Issue Date: , 2019

THIS WARRANT TO PURCHASE COMMON STOCK (the “ Warrant ”) certifies that, for value received, or its assigns (the “ Holder ”) is entitled, upon the terms and subject to the limitations on exercise and the conditions hereinafter set forth, at any time on or after [ISSUE DATE] (the “ Initial Exercise Date ”) and on or prior to 5:00 p.m. (New York City time) on , 2024 (the “ Termination Date ”) but not thereafter, to subscribe for and purchase from Vaxart, Inc., a Delaware corporation (the “ Company ”), up to shares (as subject to adjustment hereunder, the “ Warrant Shares ”) of Common Stock. The purchase price of one share of Common Stock under this Warrant shall be equal to the Exercise Price, as defined in Section 2(b).

Section 1 . Definitions . In addition to the terms defined elsewhere in this Warrant, the following terms have the meanings indicated in this Section 1:

“ Affiliate ” means any Person that, directly or indirectly through one or more intermediaries, controls or is controlled by or is under common control with a Person as such terms are used in and construed under Rule 405 under the Securities Act.

“ Bid Price ” means, for any date, the price determined by the first of the following clauses that applies: (a) if the Common Stock is then listed or quoted on a Trading Market, the bid price of the Common Stock for the time in question (or the nearest preceding date) on the Trading Market on which the Common Stock is then listed or quoted as reported by Bloomberg L.P. (based on a Trading Day from 9:30 a.m. (New York City time) to 4:02 p.m. (New York City time)), (b) if OTCQB or OTCQX is not a Trading Market, the volume weighted average price of the Common Stock for such date (or the nearest preceding date) on OTCQB or OTCQX as applicable, (c) if the Common Stock is not then listed or quoted for trading on OTCQB or OTCQX and if prices for the Common Stock are then reported in the “Pink Sheets” published by OTC Markets Group, Inc. (or a similar organization or agency succeeding to its functions of reporting prices), the most recent bid price per share of the Common Stock so reported, or (d) in all other cases, the fair market value of a share of Common Stock as determined by an independent appraiser selected in good faith by the Holders of a majority in interest of the Warrants then outstanding and reasonably acceptable to the Company, the fees and expenses of which shall be paid by the Company.

“ Business Day ” means any day except any Saturday, any Sunday, any day which is a federal legal holiday in the United States or any day on which banking institutions in the State of New York are authorized or required by law or other governmental action to close.

“ Commission ” means the United States Securities and Exchange Commission.

“ Common Stock ” means the common stock of the Company, par value $0.10 per share, and any other class of securities into which such securities may hereafter be reclassified or changed.

“ Common Stock Equivalents ” means any securities of the Company or any subsidiaries of the Company which would entitle the holder thereof to acquire at any time Common Stock, including, without limitation, any debt, preferred stock, right, option, warrant or other instrument that is at any time convertible into or exercisable or exchangeable for, or otherwise entitles the holder thereof to receive, Common Stock.

“ Exchange Act ” means the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder.

“ Person ” means an individual or corporation, partnership, trust, incorporated or unincorporated association, joint venture, limited liability company, joint stock company, government (or an agency or subdivision thereof) or other entity of any kind.

“ Registration Statement ” means the Company’s registration statement on Form S-1 (File No. 229536).

“ Securities Act ” means the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder.

“ Trading Day ” means a day on which the Common Stock is traded on a Trading Market.

“ Trading Market ” means any of the following markets or exchanges on which the Common Stock is listed or quoted for trading on the date in question: the NYSE American, the Nasdaq Capital Market, the Nasdaq Global Market, the Nasdaq Global Select Market or the New York Stock Exchange (or any successors to any of the foregoing).

“ Transfer Agent ” means American Stock Transfer & Trust Company, LLC, the current transfer agent of the Company, with a mailing address of 6201 15 th Avenue, Brooklyn, New York 11219, and any successor transfer agent of the Company.

“ VWAP ” means, for any date, the price determined by the first of the following clauses that applies: (a) if the Common Stock is then listed or quoted on a Trading Market, the daily volume weighted average price of the Common Stock for such date (or the nearest preceding date) on the Trading Market on which the Common Stock is then listed or quoted as reported by Bloomberg L.P. (based on a Trading Day from 9:30 a.m. (New York City time) to 4:02 p.m. (New York City time)), (b) if OTCQB or OTCQX is not a Trading Market, the volume weighted average price of the Common Stock for such date (or the nearest preceding date) on OTCQB or OTCQX as applicable, (c) if the Common Stock is not then listed or quoted for trading on OTCQB or OTCQX and if prices for the Common Stock are then reported in the “Pink Sheets” published by OTC Markets Group, Inc. (or a similar organization or agency succeeding to its functions of reporting prices), the most recent bid price per share of the Common Stock so reported, or (d) in all other cases, the fair market value of a share of Common Stock as determined by an independent appraiser selected in good faith by the Holders of a majority in interest of the Warrants then outstanding and reasonably acceptable to the Company, the fees and expenses of which shall be paid by the Company.

“ Warrants ” means this Warrant and other Common Stock purchase warrants issued by the Company pursuant to the Registration Statement.

Section 2 . Exercise .

(a) Exercise of Warrants . Exercise of the purchase rights represented by this Warrant may be made, in whole or in part, at any time or times on or after the Initial Exercise Date and on or before the Termination Date by delivery to the Company (or such other office or agency of the Company as it may designate by notice in writing to the registered Holder at the address of the Holder appearing on the books of the Company) of a duly executed facsimile copy (or e-mail attachment) of the Notice of Exercise in the form annexed hereto (the “ Notice of Exercise ”). Within the earlier of (i) two (2) Trading Days and (ii) the number of Trading Days comprising the Standard Settlement Period (as defined in Section 2(d)(i) herein) following the date of exercise as aforesaid, the Holder shall deliver the aggregate Exercise Price to the Company for the Warrant Shares specified in the applicable Notice of Exercise by wire transfer or cashier’s check drawn on a United States bank unless the cashless exercise procedure specified in Section 2(c) below is specified in the applicable Notice of Exercise. No ink-original Notice of Exercise shall be required, nor shall any medallion guarantee (or other type of guarantee or notarization) of any Notice of Exercise be required. Notwithstanding anything herein to the contrary, the Holder shall not be required to physically surrender this Warrant to the Company until the Holder has purchased all of the Warrant Shares available hereunder and the Warrant has been exercised in full, in which case, the Holder shall surrender this Warrant to the Company for cancellation within three (3) Trading Days of the date on which the final Notice of Exercise is delivered to the Company. Partial exercises of this Warrant resulting in purchases of a portion of the total number of Warrant Shares available hereunder shall have the effect of lowering the outstanding number of Warrant Shares purchasable hereunder in an amount equal to the applicable number of Warrant Shares purchased. The Holder and the Company shall maintain records showing the number of Warrant Shares purchased and the date of such purchases. The Company shall deliver any objection to any Notice of Exercise within one (1) Business Day of receipt of such notice. The Holder and any assignee, by acceptance of this Warrant, acknowledge and agree

that, by reason of the provisions of this paragraph, following the purchase of a portion of the Warrant Shares hereunder, the number of Warrant Shares available for purchase hereunder at any given time may be less than the amount stated on the face hereof.

Without limiting the rights of a Holder to receive Warrant Shares on a “cashless exercise” and without limiting the liquidated damages provision in Section 2(d)(i) and the buy-in provision in Section 2(d)(iv), in no event will the Company be required to net cash settle a Warrant exercise.

(b) Exercise Price . The exercise price per Warrant Share under this Warrant shall be $[•], subject to adjustment hereunder (the “ Exercise Price ”).

(c) Cashless Exercise . If at the time of exercise hereof there is no effective registration statement registering, or the prospectus contained therein is not available for the issuance of the Warrant Shares to the Holder, then this Warrant may also be exercised, in whole or in part, at such time by means of a “cashless exercise” in which the Holder shall be entitled to receive a number of Warrant Shares equal to the quotient obtained by dividing [(A-B) (X)] by (A), where:

(A) = as applicable: (i) the VWAP on the Trading Day immediately preceding the date of the applicable Notice of Exercise if such Notice of Exercise is (1) both executed and delivered pursuant to Section 2(a) hereof on a day that is not a Trading Day or (2) both executed and delivered pursuant to Section 2(a) hereof on a Trading Day prior to the opening of “regular trading hours” (as defined in Rule 600(b)(64) of Regulation NMS promulgated under the federal securities laws) on such Trading Day, (ii) at the option of the Holder, either (y) the VWAP on the Trading Day immediately preceding the date of the applicable Notice of Exercise or (z) the Bid Price of the Common Stock on the principal Trading Market as reported by Bloomberg L.P. as of the time of the Holder’s execution of the applicable Notice of Exercise if such Notice of Exercise is executed during “regular trading hours” on a Trading Day and is delivered within two (2) hours thereafter (including until two (2) hours after the close of “regular trading hours” on a Trading Day) pursuant to Section 2(a) hereof or (iii) the VWAP on the date of the applicable Notice of Exercise if the date of such Notice of Exercise is a Trading Day and such Notice of Exercise is both executed and delivered pursuant to Section 2(a) hereof after the close of “regular trading hours” on such Trading Day;

(B) = the Exercise Price, as adjusted hereunder; and

(X) = the number of Warrant Shares that would be issuable upon exercise of this Warrant in accordance with the terms of this Warrant if such exercise were by means of a cash exercise rather than a cashless exercise.

If Warrant Shares are issued in such a cashless exercise, the parties acknowledge and agree that in accordance with Section 3(a)(9) of the Securities Act, the Warrant Shares shall take on the registered characteristics of the Warrants being exercised. The Company agrees not to take any position contrary to this Section 2(c).

(d) Mechanics of Exercise .

i. Delivery of Warrant Shares Upon Exercise . The Company shall cause the Warrant Shares purchased hereunder to be transmitted by the Transfer Agent to the Holder by crediting the account of the Holder’s or its designee’s balance account with The Depository Trust Company through its Deposit or Withdrawal at Custodian system (“ DWAC ”) if the Company is then a participant in such system and either (A) there is an effective registration statement permitting the issuance of the Warrant Shares to or resale of the Warrant Shares by the Holder or (B) this Warrant is being exercised via cashless exercise and otherwise by physical delivery of a certificate, registered in the Company’s share register in the name of the Holder or its designee, for the number of Warrant Shares to which the Holder is entitled pursuant to such exercise to the address specified by the Holder in the Notice of Exercise by the date that is the earlier of (i) the earlier of (A) two (2) Trading Days after the delivery to

the Company of the Notice of Exercise and (B) one (1) Trading Day after delivery of the aggregate Exercise Price to the Company and (ii) the number of Trading Days comprising the Standard Settlement Period after the delivery to the Company of the Notice of Exercise (such date, the “ Warrant Share Delivery Date ”). Upon delivery of the Notice of Exercise, the Holder shall be deemed for all corporate purposes to have become the holder of record of the Warrant Shares with respect to which this Warrant has been exercised, irrespective of the date of delivery of the Warrant Shares, provided that payment of the aggregate Exercise Price (other than in the case of a cashless exercise) is received within the earlier of (i) two (2) Trading Days and (ii) the number of Trading Days comprising the Standard Settlement Period following delivery of the Notice of Exercise. If the Company fails for any reason to deliver to the Holder the Warrant Shares subject to a Notice of Exercise by the Warrant Share Delivery Date, the Company shall pay to the Holder, in cash, as liquidated damages and not as a penalty, for each $1,000 of Warrant Shares subject to such exercise (based on the VWAP of the Common Stock on the date of the applicable Notice of Exercise), $10 per Trading Day (increasing to $20 per Trading Day on the fifth (5 th) Trading Day after such liquidated damages begin to accrue) for each Trading Day after such Warrant Share Delivery Date until such Warrant Shares are delivered or Holder rescinds such exercise. The Company agrees to maintain a transfer agent that is a participant in the FAST program so long as this Warrant remains outstanding and exercisable. As used herein, “ Standard Settlement Period ” means the standard settlement period, expressed in a number of Trading Days, on the Company’s primary Trading Market with respect to the Common Stock as in effect on the date of delivery of the Notice of Exercise.

ii. Delivery of New Warrants Upon Exercise . If this Warrant shall have been exercised in part, the Company shall, at the request of a Holder and upon surrender of this Warrant certificate, at the time of delivery of the Warrant Shares, deliver to the Holder a new Warrant evidencing the rights of the Holder to purchase the unpurchased Warrant Shares called for by this Warrant, which new Warrant shall in all other respects be identical with this Warrant.

iii. Rescission Rights . If the Company fails to cause the Transfer Agent to transmit to the Holder the Warrant Shares pursuant to Section 2(d)(i) by the Warrant Share Delivery Date, then the Holder will have the right to rescind such exercise.

iv. Compensation for Buy-In on Failure to Timely Deliver Warrant Shares Upon Exercise . In addition to any other rights available to the Holder, if the Company fails to cause the Transfer Agent to transmit to the Holder the Warrant Shares in accordance with the provisions of Section 2(d)(i) above pursuant to an exercise on or before the Warrant Share Delivery Date, and if after such date the Holder is required by its broker to purchase (in an open market transaction or otherwise) or the Holder’s brokerage firm otherwise purchases, shares of Common Stock to deliver in satisfaction of a sale by the Holder of the Warrant Shares which the Holder anticipated receiving upon such exercise but did not receive (a “ Buy-In ”), then the Company shall (A) pay in cash to the Holder the amount, if any, by which (x) the Holder’s total purchase price (including brokerage commissions, if any) for the shares of Common Stock so purchased exceeds (y) the amount obtained by multiplying (1) the number of Warrant Shares that the Company was required to deliver, but failed to deliver, to the Holder in connection with the exercise at issue times (2) the price at which the sell order giving rise to such purchase obligation was executed, and (B) at the option of the Holder, either reinstate the portion of the Warrant and equivalent number of Warrant Shares for which such exercise was not honored (in which case such exercise shall be deemed rescinded) or deliver to the Holder the number of shares of Common Stock that would have been issued had the Company timely complied with its exercise and delivery obligations hereunder. For example, if the Holder purchases Common Stock having a total purchase price of $11,000 to cover a Buy-In with respect to an attempted exercise of shares of Common Stock with an aggregate sale price giving rise to such purchase obligation of $10,000, under clause (A) of the immediately preceding sentence the Company shall be required to pay the Holder $1,000. The Holder shall provide the Company written notice indicating the amounts payable to the Holder in respect of the Buy-In and, upon request of the Company, evidence of the amount of such loss. Nothing herein shall limit a Holder’s right to pursue any other remedies available to it hereunder, at law or in equity including, without limitation, a decree of specific performance and/or injunctive relief with respect to the Company’s failure to timely deliver shares of Common Stock upon exercise of the Warrant as required pursuant to the terms hereof.

v. No Fractional Shares or Scrip . No fractional shares or scrip representing fractional shares shall be issued upon the exercise of this Warrant. As to any fraction of a share

which the Holder would otherwise be entitled to purchase upon such exercise, the Company shall, at its election, either pay a cash adjustment in respect of such final fraction in an amount equal to such fraction multiplied by the Exercise Price or round up to the next whole share.

vi. Charges, Taxes and Expenses . Issuance of Warrant Shares shall be made without charge to the Holder for any issue or transfer tax or other incidental expense in respect of the issuance of such Warrant Shares, all of which taxes and expenses shall be paid by the Company, and such Warrant Shares shall be issued in the name of the Holder or in such name or names as may be directed by the Holder; provided , however , that in the event that Warrant Shares are to be issued in a name other than the name of the Holder, this Warrant when surrendered for exercise shall be accompanied by the Assignment Form attached hereto duly executed by the Holder and the Company may require, as a condition thereto, the payment of a sum sufficient to reimburse it for any transfer tax incidental thereto. The Company shall pay all Transfer Agent fees required for same-day processing of any Notice of Exercise and all fees to the Depository Trust Company (or another established clearing corporation performing similar functions) required for same-day electronic delivery of the Warrant Shares.

vii. Closing of Books . The Company will not close its stockholder books or records in any manner which prevents the timely exercise of this Warrant, pursuant to the terms hereof.

(e) Holder’s Exercise Limitations . The Company shall not effect any exercise of this Warrant, and a Holder shall not have the right to exercise any portion of this Warrant, pursuant to Section 2 or otherwise, to the extent that after giving effect to such issuance after exercise as set forth on the applicable Notice of Exercise, the Holder (together with the Holder’s Affiliates, and any other Persons acting as a group together with the Holder or any of the Holder’s Affiliates (such Persons, “ Attribution Parties ”)), would beneficially own in excess of the Beneficial Ownership Limitation (as defined below). For purposes of the foregoing sentence, the number of shares of Common Stock beneficially owned by the Holder and its Affiliates and Attribution Parties shall include the number of shares of Common Stock issuable upon exercise of this Warrant with respect to which such determination is being made, but shall exclude the number of shares of Common Stock which would be issuable upon (i) exercise of the remaining, nonexercised portion of this Warrant beneficially owned by the Holder or any of its Affiliates or Attribution Parties and (ii) exercise or conversion of the unexercised or nonconverted portion of any other securities of the Company (including, without limitation, any other Common Stock Equivalents) subject to a limitation on conversion or exercise analogous to the limitation contained herein beneficially owned by the Holder or any of its Affiliates or Attribution Parties. Except as set forth in the preceding sentence, for purposes of this Section 2(e), beneficial ownership shall be calculated in accordance with Section 13(d) of the Exchange Act and the rules and regulations promulgated thereunder, it being acknowledged by the Holder that the Company is not representing to the Holder that such calculation is in compliance with Section 13(d) of the Exchange Act and the Holder is solely responsible for any schedules required to be filed in accordance therewith. To the extent that the limitation contained in this Section 2(e) applies, the determination of whether this Warrant is exercisable (in relation to other securities owned by the Holder together with any Affiliates and Attribution Parties) and of which portion of this Warrant is exercisable shall be in the sole discretion of the Holder, and the submission of a Notice of Exercise shall be deemed to be the Holder’s determination of whether this Warrant is exercisable (in relation to other securities owned by the Holder together with any Affiliates and Attribution Parties) and of which portion of this Warrant is exercisable, in each case subject to the Beneficial Ownership Limitation, and the Company shall have no obligation to verify or confirm the accuracy of such determination. In addition, a determination as to any group status as contemplated above shall be determined in accordance with Section 13(d) of the Exchange Act and the rules and regulations promulgated thereunder. For purposes of this Section 2(e), in determining the number of outstanding shares of Common Stock, a Holder may rely on the number of outstanding shares of Common Stock as reflected in (A) the Company’s most recent periodic or annual report filed with the Commission, as the case may be, (B) a more recent public announcement by the Company or (C) a more recent written notice by the Company or the Transfer Agent setting forth the number of shares of Common Stock outstanding. Upon the written or oral request of a Holder, the Company shall within one (1) Trading Day confirm orally and in writing to the Holder the number of shares of Common Stock then outstanding. In any case, the number of outstanding shares of Common Stock shall be determined after giving effect to the conversion or exercise of securities of the Company, including this Warrant, by the Holder or its Affiliates or Attribution Parties since the date as of which such number of outstanding shares of Common Stock was reported. The “ Beneficial Ownership Limitation ” shall be [9.99/4.99%] of the number of shares of the Common Stock outstanding immediately after giving effect to the issuance of shares of Common Stock issuable upon exercise of this Warrant. The Holder, upon notice to the Company, may increase or decrease the Beneficial Ownership Limitation provisions of this Section 2(e), provided that the Beneficial Ownership Limitation

in no event exceeds 9.99% of the number of shares of the Common Stock outstanding immediately after giving effect to the issuance of shares of Common Stock upon exercise of this Warrant held by the Holder and the provisions of this Section 2(e) shall continue to apply. Any increase in the Beneficial Ownership Limitation will not be effective until the 61 st day after such notice is delivered to the Company. The provisions of this paragraph shall be construed and implemented in a manner otherwise than in strict conformity with the terms of this Section 2(e) to correct this paragraph (or any portion hereof) which may be defective or inconsistent with the intended Beneficial Ownership Limitation herein contained or to make changes or supplements necessary or desirable to properly give effect to such limitation. The limitations contained in this paragraph shall apply to a successor holder of this Warrant.

Section 3 . Certain Adjustments .

(a) Stock Dividends and Splits . If the Company, at any time while this Warrant is outstanding: (i) pays a stock dividend or otherwise makes a distribution or distributions on shares of its Common Stock or any other equity or equity equivalent securities payable in shares of Common Stock (which, for avoidance of doubt, shall not include any shares of Common Stock issued by the Company upon exercise of this Warrant), (ii) subdivides outstanding shares of Common Stock into a larger number of shares, (iii) combines (including by way of reverse stock split) outstanding shares of Common Stock into a smaller number of shares, or (iv) issues by reclassification of shares of the Common Stock any shares of capital stock of the Company, then in each case the Exercise Price shall be multiplied by a fraction of which the numerator shall be the number of shares of Common Stock (excluding treasury shares, if any) outstanding immediately before such event and of which the denominator shall be the number of shares of Common Stock outstanding immediately after such event, and the number of shares issuable upon exercise of this Warrant shall be proportionately adjusted such that the aggregate Exercise Price of this Warrant shall remain unchanged. Any adjustment made pursuant to this Section 3(a) shall become effective immediately after the record date for the determination of stockholders entitled to receive such dividend or distribution and shall become effective immediately after the effective date in the case of a subdivision, combination or re-classification.

(b) Subsequent Rights Offerings . In addition to any adjustments pursuant to Section 3(a) above, if at any time the Company grants, issues or sells any Common Stock Equivalents or rights to purchase stock, warrants, securities or other property pro rata to the record holders of any class of shares of Common Stock (the “ Purchase Rights ”), then the Holder will be entitled to acquire, upon the terms applicable to such Purchase Rights, the aggregate Purchase Rights which the Holder could have acquired if the Holder had held the number of shares of Common Stock acquirable upon complete exercise of this Warrant (without regard to any limitations on exercise hereof, including without limitation, the Beneficial Ownership Limitation) immediately before the date on which a record is taken for the grant, issuance or sale of such Purchase Rights, or, if no such record is taken, the date as of which the record holders of shares of Common Stock are to be determined for the grant, issue or sale of such Purchase Rights (provided, however, to the extent that the Holder’s right to participate in any such Purchase Right would result in the Holder exceeding the Beneficial Ownership Limitation, then the Holder shall not be entitled to participate in such Purchase Right to such extent (or beneficial ownership of such shares of Common Stock as a result of such Purchase Right to such extent) and such Purchase Right to such extent shall be held in abeyance for the Holder until such time, if ever, as its right thereto would not result in the Holder exceeding the Beneficial Ownership Limitation).

(c) Pro Rata Distributions . During such time as this Warrant is outstanding, if the Company shall declare or make any dividend or other distribution of its assets (or rights to acquire its assets) to holders of shares of Common Stock other than as set forth in Section 3(a), by way of return of capital or otherwise (including, without limitation, any distribution of cash, stock or other securities, property or options by way of a dividend, spin off, reclassification, corporate rearrangement, scheme of arrangement or other similar transaction) (a “ Distribution ”), at any time after the issuance of this Warrant, then, in each such case, the Holder shall be entitled to participate in such Distribution to the same extent that the Holder would have participated therein if the Holder had held the number of shares of Common Stock acquirable upon complete exercise of this Warrant (without regard to any limitations on exercise hereof, including without limitation, the Beneficial Ownership Limitation) immediately before the date of which a record is taken for such Distribution, or, if no such record is taken, the date as of which the record holders of shares of Common Stock are to be determined for the participation in such Distribution ( provided , however , to the extent that the Holder’s right to participate in any such Distribution would result in the Holder exceeding the Beneficial Ownership Limitation, then the Holder shall not be entitled to participate in such Distribution to such extent (or in the beneficial ownership of any shares of Common Stock as a result of such Distribution to such extent)

and the portion of such Distribution shall be held in abeyance for the benefit of the Holder until such time, if ever, as its right thereto would not result in the Holder exceeding the Beneficial Ownership Limitation).

(d) Fundamental Transaction . If, at any time while this Warrant is outstanding, (i) the Company, directly or indirectly, in one or more related transactions effects any merger or consolidation of the Company with or into another Person, (ii) the Company, directly or indirectly, effects any sale, lease, license, assignment, transfer, conveyance or other disposition of all or substantially all of its assets in one or a series of related transactions, (iii) any, direct or indirect, purchase offer, tender offer or exchange offer (whether by the Company or another Person) is completed pursuant to which holders of Common Stock are permitted to sell, tender or exchange their shares for other securities, cash or property and has been accepted by the holders of 50% or more of the outstanding Common Stock, (iv) the Company, directly or indirectly, in one or more related transactions effects any reclassification, reorganization or recapitalization of the Common Stock or any compulsory share exchange pursuant to which the Common Stock is effectively converted into or exchanged for other securities, cash or property, or (v) the Company, directly or indirectly, in one or more related transactions consummates a stock or share purchase agreement or other business combination (including, without limitation, a reorganization, recapitalization, spin-off or scheme of arrangement) with another Person or group of Persons whereby such other Person or group acquires more than 50% of the outstanding shares of Common Stock (not including any shares of Common Stock held by the other Person or other Persons making or party to, or associated or affiliated with the other Persons making or party to, such stock or share purchase agreement or other business combination) (each a “ Fundamental Transaction ”), then, upon any subsequent exercise of this Warrant, the Holder shall have the right to receive, for each Warrant Share that would have been issuable upon such exercise immediately prior to the occurrence of such Fundamental Transaction, at the option of the Holder (without regard to any limitation in Section 2(e) on the exercise of this Warrant), the number of shares of Common Stock of the successor or acquiring corporation or of the Company, if it is the surviving corporation, and/or any additional consideration (the “ Alternate Consideration “) receivable as a result of such Fundamental Transaction by a holder of the number of shares of Common Stock for which this Warrant is exercisable immediately prior to such Fundamental Transaction (without regard to any limitation in Section 2(e) on the exercise of this Warrant). For purposes of any such exercise, the determination of the Exercise Price shall be appropriately adjusted to apply to such Alternate Consideration based on the amount of Alternate Consideration issuable in respect of one share of Common Stock in such Fundamental Transaction, and the Company shall apportion the Exercise Price among the Alternate Consideration in a reasonable manner reflecting the relative value of any different components of the Alternate Consideration. If holders of Common Stock are given any choice as to the securities, cash or property to be received in a Fundamental Transaction, then the Holder shall be given the same choice as to the Alternate Consideration it receives upon any exercise of this Warrant following such Fundamental Transaction. Notwithstanding anything to the contrary, in the event of a Fundamental Transaction, the Company or any Successor Entity (as defined below) shall, at the Holder’s option, exercisable at any time concurrently with, or within 30 days after, the consummation of the Fundamental Transaction (or, if later, the date of the public announcement of the applicable Fundamental Transaction), purchase this Warrant from the Holder by paying to the Holder an amount of cash equal to the Black Scholes Value of the remaining unexercised portion of this Warrant on the date of the consummation of such Fundamental Transaction; provided , however , if the Fundamental Transaction is not within the Company’s control, including not approved by the Company’s Board of Directors, Holder shall only be entitled to receive from the Company or any Successor Entity, as of the date of consummation of such Fundamental Transaction, the same type or form of consideration (and in the same proportion), at the Black Scholes Value (as defined below) of the unexercised portion of this Warrant, that is being offered and paid to the holders of Common Stock of the Company in connection with the Fundamental Transaction, whether that consideration be in the form of cash, stock or any combination thereof, or whether the holders of Common Stock are given the choice to receive from among alternative forms of consideration in connection with the Fundamental Transaction. “ Black Scholes Value ” means the value of this Warrant based on the Black and Scholes Option Pricing Model obtained from the “OV” function on Bloomberg, L.P. (“ Bloomberg ”) determined as of the day of consummation of the applicable Fundamental Transaction for pricing purposes and reflecting (A) a risk-free interest rate corresponding to the U.S. Treasury rate for a period equal to the time between the date of the public announcement of the applicable Fundamental Transaction and the Termination Date, (B) an expected volatility equal to the greater of 100% and the 100 day volatility obtained from the HVT function on Bloomberg as of the Trading Day immediately following the public announcement of the applicable Fundamental Transaction, (C) the underlying price per share used in such calculation shall be the greater of (i) the sum of the price per share being offered in cash, if any, plus the value of any non-cash consideration, if any, being offered in such Fundamental Transaction and (ii) the greater of (x) the last VWAP immediately prior to the public announcement of such Fundamental Transaction and (y) the last VWAP immediately prior to the consummation of such Fundamental Transaction and (D) a remaining option time equal to the time between the date of the public announcement of the applicable Fundamental Transaction and the Termination Date. The payment of the Black Scholes Value will be made by wire transfer of immediately available funds within five Business Days of the Holder’s election (or, if later, on the effective date of the Fundamental Transaction). The Company shall cause any successor entity in a Fundamental Transaction in which the Company is not the survivor (the “ Successor Entity ”) to assume in writing all of the obligations of the Company under this Warrant in accordance with the provisions of this Section 3(d) pursuant to written agreements in form and substance reasonably satisfactory to the Holder and approved by the Holder (without unreasonable delay) prior to such Fundamental Transaction and shall, at the option of the Holder, deliver to the Holder in exchange for this Warrant a security of the Successor Entity evidenced by a written instrument substantially similar in form and substance to this Warrant which is exercisable for a corresponding number of shares of capital stock of such Successor Entity (or its parent entity) equivalent to the shares of Common Stock acquirable and receivable upon exercise of this Warrant (without regard to any limitations on the exercise of this Warrant) prior to such Fundamental Transaction, and with an Exercise price which applies the Exercise price hereunder to such shares of capital stock (but taking into account the relative value of the shares of Common Stock pursuant to such Fundamental Transaction and the value of such shares of capital stock, such number of shares of capital stock and such exercise price being for the purpose of protecting the economic value of this Warrant immediately prior to the consummation of such Fundamental Transaction), and which is reasonably satisfactory in form and substance to the Holder. Upon the occurrence of any such Fundamental Transaction, the Successor Entity shall succeed to, and be substituted for (so that from and after the date of such Fundamental Transaction, the provisions of this Warrant referring to the “Company” shall refer instead to the Successor Entity), and may exercise every right and power of the Company and shall assume all of the obligations of the Company under this Warrant with the same effect as if such Successor Entity had been named as the Company herein.

(e) Calculations . All calculations under this Section 3 shall be made to the nearest cent or the nearest 1/100th of a share, as the case may be. For purposes of this Section 3, the number of shares of Common Stock deemed to be issued and outstanding as of a given date shall be the sum of the number of shares of Common Stock (excluding treasury shares, if any) issued and outstanding.

(f) Notice to Holder .

i. Adjustment to Exercise Price . Whenever the Exercise Price is adjusted pursuant to any provision of this Section 3, the Company shall promptly deliver to the Holder by facsimile or email a notice setting forth the Exercise Price after such adjustment and any resulting adjustment to the number of Warrant Shares and setting forth a brief statement of the facts requiring such adjustment.

ii. Notice to Allow Exercise by Holder . If (A) the Company shall declare a dividend (or any other distribution in whatever form) on the Common Stock, (B) the Company shall declare a special nonrecurring cash dividend on or a redemption of the Common Stock, (C) the Company shall authorize the granting to all holders of the Common Stock rights or warrants to subscribe for or purchase any shares of capital stock of any class or of any rights, (D) the approval of any stockholders of the Company shall be required in connection with any reclassification of the Common Stock, any consolidation or merger to which the Company is a party, any sale or transfer of all or substantially all of the assets of the Company, or any compulsory share exchange whereby the Common Stock is converted into other securities, cash or property, or (E) the Company shall authorize the voluntary or involuntary dissolution, liquidation or winding up of the affairs of the Company, then, in each case, the Company shall cause to be delivered by facsimile or email to the Holder at its last facsimile number or email address as it shall appear upon the Warrant Register of the Company, at least 20 calendar days prior to the applicable record or effective date hereinafter specified, a notice stating (x) the date on which a record is to be taken for the purpose of such dividend, distribution, redemption, rights or warrants, or if a record is not to be taken, the date as of which the holders of the Common Stock of record to be entitled to such dividend, distributions, redemption, rights or warrants are to be determined or (y) the date on which such reclassification, consolidation, liquidation, merger, sale, transfer or share exchange is expected to become effective or close, and the date as of which it is expected that holders of the Common Stock of record shall be entitled to exchange their shares of the Common Stock for securities, cash or other property deliverable upon such reclassification, consolidation, liquidation, merger, sale, transfer or share exchange; provided that the failure to deliver such notice or any defect therein or in the delivery thereof shall not affect the validity of the corporate action required to be specified in such notice. To the extent that any notice provided in this Warrant constitutes, or contains, material, non-public information regarding the Company or any subsidiaries of the Company, the Company shall simultaneously file such notice with the Commission pursuant to a Current Report on Form 8-K. The Holder shall remain entitled to exercise this Warrant during the period commencing on the date of such notice to the effective date of the event triggering such notice except as may otherwise be expressly set forth herein.

Section 4 . Transfer of Warrant .

(a) Transferability . This Warrant and all rights hereunder (including, without limitation, any registration rights) are transferable, in whole or in part, upon surrender of this Warrant at the principal office of the Company or its designated agent, together with a written assignment of this Warrant substantially in the form attached hereto duly executed by the Holder or its agent or attorney and funds sufficient to pay any transfer taxes payable upon the making of such transfer. Upon such surrender and, if required, such payment, the Company shall execute and deliver a new Warrant or Warrants in the name of the assignee or assignees, as applicable, and in the denomination or denominations specified in such instrument of assignment, and shall issue to the assignor a new Warrant evidencing the portion of this Warrant not so assigned, and this Warrant shall promptly be cancelled. Notwithstanding anything herein to the contrary, the Holder shall not be required to physically surrender this Warrant to the Company unless the Holder has assigned this Warrant in full, in which case, the Holder shall surrender this Warrant to the Company within two (2) Trading Days of the date on which the Holder delivers an assignment form to the Company assigning this Warrant in full. The Warrant, if properly assigned in accordance

herewith, may be exercised by a new holder for the purchase of Warrant Shares without having a new Warrant issued.

(b) New Warrants . This Warrant may be divided or combined with other Warrants upon presentation hereof at the aforesaid office of the Company, together with a written notice specifying the names and denominations in which new Warrants are to be issued, signed by the Holder or its agent or attorney. Subject to compliance with Section 4(a), as to any transfer which may be involved in such division or combination, the Company shall execute and deliver a new Warrant or Warrants in exchange for the Warrant or Warrants to be divided or combined in accordance with such notice. All Warrants issued on transfers or exchanges shall be dated the Issue Date of this Warrant and shall be identical with this Warrant except as to the number of Warrant Shares issuable pursuant thereto.

(c) Warrant Register . The Company shall register this Warrant, upon records to be maintained by the Company for that purpose (the “ Warrant Register ”), in the name of the record Holder hereof from time to time. The Company may deem and treat the registered Holder of this Warrant as the absolute owner hereof for the purpose of any exercise hereof or any distribution to the Holder, and for all other purposes, absent actual notice to the contrary.

Section 5 . Miscellaneous .

(a) No Rights as Stockholder Until Exercise . This Warrant does not entitle the Holder to any voting rights, dividends or other rights as a stockholder of the Company prior to the exercise hereof as set forth in Section 2(d)(i), except as expressly set forth in Section 3.

(b) Loss, Theft, Destruction or Mutilation of Warrant . The Company covenants that upon receipt by the Company of evidence reasonably satisfactory to it of the loss, theft, destruction or mutilation of this Warrant or any stock certificate relating to the Warrant Shares, and in case of loss, theft or destruction, of indemnity or security reasonably satisfactory to it (which, in the case of the Warrant, shall not include the posting of any bond), and upon surrender and cancellation of such Warrant or stock certificate, if mutilated, the Company will make and deliver a new Warrant or stock certificate of like tenor and dated as of such cancellation, in lieu of such Warrant or stock certificate.

(c) Saturdays, Sundays, Holidays, etc . If the last or appointed day for the taking of any action or the expiration of any right required or granted herein shall not be a Business Day, then, such action may be taken or such right may be exercised on the next succeeding Business Day.

(d) Authorized Shares .

The Company covenants that during the period the Warrant is outstanding, it will reserve from its authorized and unissued Common Stock a sufficient number of shares to provide for the issuance of the Warrant Shares upon the exercise of any purchase rights under this Warrant. The Company further covenants that its issuance of this Warrant shall constitute full authority to its officers who are charged with the duty of issuing the necessary Warrant Shares upon the exercise of the purchase rights under this Warrant. The Company will take all such reasonable action as may be necessary to assure that such Warrant Shares may be issued as provided herein without violation of any applicable law or regulation, or of any requirements of the Trading Market upon which the Common Stock may be listed. The Company covenants that all Warrant Shares which may be issued upon the exercise of the purchase rights represented by this Warrant will, upon exercise of the purchase rights represented by this Warrant and payment for such Warrant Shares in accordance herewith, be duly authorized, validly issued, fully paid and nonassessable and free from all taxes, liens and charges created by the Company in respect of the issue thereof (other than taxes in respect of any transfer occurring contemporaneously with such issue).

Except and to the extent as waived or consented to by the Holder, the Company shall not by any action, including, without limitation, amending its certificate of incorporation or through any reorganization, transfer of assets, consolidation, merger, dissolution, issue or sale of securities or any other voluntary action, avoid or seek to avoid the observance or performance of any of the terms of this Warrant, but will at all times in good faith assist in the carrying out of all such terms and in the taking of all such actions as may be necessary or appropriate to protect the rights of Holder as set forth in this Warrant against impairment. Without limiting the generality of the foregoing, the Company will (i) not increase the par value of any Warrant Shares above the amount payable therefor upon such exercise immediately prior to such increase in par value, (ii) take all such action as may be necessary or appropriate in order that the Company may validly and legally issue fully paid and nonassessable Warrant Shares upon the

exercise of this Warrant and (iii) use commercially reasonable efforts to obtain all such authorizations, exemptions or consents from any public regulatory body having jurisdiction thereof, as may be, necessary to enable the Company to perform its obligations under this Warrant.

Before taking any action which would result in an adjustment in the number of Warrant Shares for which this Warrant is exercisable or in the Exercise Price, the Company shall obtain all such authorizations or exemptions thereof, or consents thereto, as may be necessary from any public regulatory body or bodies having jurisdiction thereof.

(e) Jurisdiction . All questions concerning the construction, validity, enforcement and interpretation of this Warrant shall be governed by and construed and enforced in accordance with the internal laws of the State of New York, without regard to the principles of conflicts of law thereof. Each party agrees that all legal proceedings concerning the interpretations, enforcement and defense of the transactions contemplated by this Warrant (whether brought against a party hereto or their respective affiliates, directors, officers, shareholders, partners, members, employees or agents) shall be commenced exclusively in the state and federal courts sitting in the City of New York. Each party hereby irrevocably submits to the exclusive jurisdiction of the state and federal courts sitting in the City of New York, Borough of Manhattan for the adjudication of any dispute hereunder or in connection herewith or with any transaction contemplated hereby or discussed herein, and hereby irrevocably waives, and agrees not to assert in any suit, action or proceeding, any claim that it is not personally subject to the jurisdiction of any such court, that such suit, action or proceeding is improper or is an inconvenient venue for such proceeding. Each party hereby irrevocably waives personal service of process and consents to process being served in any such suit, action or proceeding by mailing a copy thereof via registered or certified mail or overnight delivery (with evidence of delivery) to such party at the address in effect for notices to it under this Warrant and agrees that such service shall constitute good and sufficient service of process and notice thereof. Nothing contained herein shall be deemed to limit in any way any right to serve process in any other manner permitted by law. If either party shall commence an action, suit or proceeding to enforce any provisions of this Warrant, the prevailing party in such action, suit or proceeding shall be reimbursed by the other party for their reasonable attorneys’ fees and other costs and expenses incurred with the investigation, preparation and prosecution of such action or proceeding.

(f) Restrictions . The Holder acknowledges that the Warrant Shares acquired upon the exercise of this Warrant, if not registered, and the Holder does not utilize cashless exercise, will have restrictions upon resale imposed by state and federal securities laws.

(g) Nonwaiver and Expenses . No course of dealing or any delay or failure to exercise any right hereunder on the part of Holder shall operate as a waiver of such right or otherwise prejudice the Holder’s rights, powers or remedies. Without limiting any other provision of this Warrant, if the Company willfully and knowingly fails to comply with any provision of this Warrant, which results in any material damages to the Holder, the Company shall pay to the Holder such amounts as shall be sufficient to cover any costs and expenses including, but not limited to, reasonable attorneys’ fees, including those of appellate proceedings, incurred by the Holder in collecting any amounts due pursuant hereto or in otherwise enforcing any of its rights, powers or remedies hereunder.

(h) Notices . Any and all notices or other communications or deliveries to be provided by the Holders hereunder including, without limitation, any Notice of Exercise, shall be in writing and delivered personally, by facsimile or e-mail, or sent by a nationally recognized overnight courier service, addressed to the Company, at Vaxart, Inc., 290 Utah Ave., Suite 200, South San Francisco, California 94080, Attention: Principal Accounting Officer, facsimile number: (650) 871-8580, email address: mecherd@vaxart.com, or such other facsimile number, email address or address as the Company may specify for such purposes by notice to the Holders. Any and all notices or other communications or deliveries to be provided by the Company hereunder shall be in writing and delivered personally, by facsimile or e-mail, or sent by a nationally recognized overnight courier service addressed to each Holder at the facsimile number, e-mail address or address of such Holder appearing on the books of the Company. Any notice or other communication or deliveries hereunder shall be deemed given and effective on the earliest of (i) the date of transmission, if such notice or communication is delivered via facsimile at the facsimile number or via e-mail at the e-mail address set forth in this Section prior to 5:30 p.m. (New York City time) on any date, (ii) the next Trading Day after the date of transmission, if such notice or communication is delivered via facsimile at the facsimile number or via e-mail at the e-mail address set forth in this Section on a day that is not a Trading Day or later than 5:30 p.m. (New York City time) on any Trading Day, (iii) the second Trading Day following the date of mailing, if sent by U.S. nationally recognized overnight courier service, or (iv) upon actual receipt by the party to whom such notice is required to be given. To the extent that any notice provided hereunder

constitutes, or contains, material, non-public information regarding the Company or any subsidiaries, the Company shall simultaneously file such notice with the Commission pursuant to a Current Report on Form 8-K.

(i) Limitation of Liability . No provision hereof, in the absence of any affirmative action by the Holder to exercise this Warrant to purchase Warrant Shares, and no enumeration herein of the rights or privileges of the Holder, shall give rise to any liability of the Holder for the purchase price of any Common Stock or as a stockholder of the Company, whether such liability is asserted by the Company or by creditors of the Company.

(j) Remedies . The Holder, in addition to being entitled to exercise all rights granted by law, including recovery of damages, will be entitled to specific performance of its rights under this Warrant. The Company agrees that monetary damages would not be adequate compensation for any loss incurred by reason of a breach by it of the provisions of this Warrant and hereby agrees to waive and not to assert the defense in any action for specific performance that a remedy at law would be adequate.

(k) Successors and Assigns . Subject to applicable securities laws, this Warrant and the rights and obligations evidenced hereby shall inure to the benefit of and be binding upon the successors and permitted assigns of the Company and the successors and permitted assigns of Holder. The provisions of this Warrant are intended to be for the benefit of any Holder from time to time of this Warrant and shall be enforceable by the Holder or holder of Warrant Shares.

(l) Amendment . This Warrant may be modified or amended or the provisions hereof waived with the written consent of the Company and the Holder.

(m) Severability . Wherever possible, each provision of this Warrant shall be interpreted in such manner as to be effective and valid under applicable law, but if any provision of this Warrant shall be prohibited by or invalid under applicable law, such provision shall be ineffective to the extent of such prohibition or invalidity, without invalidating the remainder of such provisions or the remaining provisions of this Warrant.

(n) Headings . The headings used in this Warrant are for the convenience of reference only and shall not, for any purpose, be deemed a part of this Warrant.

********************

(Signature Page Follows)

IN WITNESS WHEREOF, the Company has caused this Warrant to be executed by its officer thereunto duly authorized as of the date first above indicated.

	VAXART, INC.

	By:
		Name:
		Title:

NOTICE OF EXERCISE

TO: VAXART, INC.

(1) The undersigned hereby elects to purchase Warrant Shares of the Company pursuant to the terms of the attached Warrant (only if exercised in full), and tenders herewith payment of the exercise price in full, together with all applicable transfer taxes, if any.

(2) Payment shall take the form of (check applicable box):

o in lawful money of the United States; or

o if permitted the cancellation of such number of Warrant Shares as is necessary, in accordance with the formula set forth in subsection 2(c), to exercise this Warrant with respect to the maximum number of Warrant Shares purchasable pursuant to the cashless exercise procedure set forth in subsection 2(c).

(3) Please issue said Warrant Shares in the name of the undersigned or in such other name as is specified below:

The Warrant Shares shall be delivered to the following DWAC Account Number:

[SIGNATURE OF HOLDER]

Name of Investing Entity:
Signature of Authorized Signatory of Investing Entity :
Name of Authorized Signatory:
Title of Authorized Signatory:
Date:

EXHIBIT B

ASSIGNMENT FORM

(To assign the foregoing Warrant, execute this form and supply required information. Do not use this form to purchase shares.)

FOR VALUE RECEIVED, the foregoing Warrant and all rights evidenced thereby are hereby assigned to

Name:
	(Please Print)
Address:
	(Please Print)

Phone Number:

Email Address:

Dated:

Holder’s Signature:

Holder’s Address:

Exhibit 4.5

REPRESENTATIVE COMMON STOCK PURCHASE WARRANT

VAXART, INC.

Warrant Shares:
	Issue Date:

THIS WARRANT TO PURCHASE COMMON STOCK (the “ Warrant ”) certifies that, for value received, (the “ Holder ”) is entitled, upon the terms and subject to the limitations on exercise and the conditions hereinafter set forth, at any time on or after the date hereof (the “ Initial Exercise Date ”) and on or prior to 5:00 p.m. (New York City time) on , 2024 (the “ Termination Date ”), but not thereafter, to subscribe for and purchase from Vaxart, Inc., a Delaware corporation (the “ Company ”), up to shares (as subject to adjustment hereunder, the “ Warrant Shares ”) of Common Stock. The purchase price of one share of Common Stock under this Warrant shall be equal to the Exercise Price, as defined in Section 2(b). This Warrant is issued pursuant to that certain Underwriting Agreement, by and between the Company and H.C. Wainwright & Co., LLC as representative of the several underwriters listed in Schedule A thereto, dated as of , 2019 (the “Underwriting Agreement”).

Section 1 . Definitions . In addition to the terms defined elsewhere in this Warrant, the following terms have the meanings indicated in this Section 1:

“ Commission ” means the United States Securities and Exchange Commission.

“ Common Stock ” means the common stock of the Company, par value $0.10 per share, and any other class of securities into which such securities may hereafter be reclassified or changed.

“ Exchange Act ” means the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder.

“ Securities Act ” means the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder.

“ Trading Day ” means a day on which the Common Stock is traded on a Trading Market.

“ Warrants ” means this Warrant.

Section 2 . Exercise .

number of Warrant Shares purchasable hereunder in an amount equal to the applicable number of Warrant Shares purchased. The Holder and the Company shall maintain records showing the number of Warrant Shares purchased and the date of such purchases. The Company shall deliver any objection to any Notice of Exercise within one (1) Business Day of receipt of such notice. The Holder and any assignee, by acceptance of this Warrant, acknowledge and agree that, by reason of the provisions of this paragraph, following the purchase of a portion of the Warrant Shares hereunder, the number of Warrant Shares available for purchase hereunder at any given time may be less than the amount stated on the face hereof.

(b) Exercise Price . The exercise price per Warrant Share under this Warrant shall be $ , subject to adjustment hereunder (the “Exercise Price”).

(B) = the Exercise Price, as adjusted hereunder; and

(d) Mechanics of Exercise .

(“ DWAC ”) if the Company is then a participant in such system and either (A) there is an effective registration statement permitting the issuance of the Warrant Shares to or resale of the Warrant Shares by the Holder or (B) this Warrant is being exercised via cashless exercise and otherwise by physical delivery of a certificate, registered in the Company’s share register in the name of the Holder or its designee, for the number of Warrant Shares to which the Holder is entitled pursuant to such exercise to the address specified by the Holder in the Notice of Exercise by the date that is the earlier of (i) two (2) Trading Days and (ii) the number of Trading Days comprising the Standard Settlement Period after the delivery to the Company of the Notice of Exercise (such date, the “ Warrant Share Delivery Date ”). Upon delivery of the Notice of Exercise, the Holder shall be deemed for all corporate purposes to have become the holder of record of the Warrant Shares with respect to which this Warrant has been exercised, irrespective of the date of delivery of the Warrant Shares, provided that payment of the aggregate Exercise Price (other than in the case of a cashless exercise) is received within the earlier of (i) two (2) Trading Days and (ii) the number of Trading Days comprising the Standard Settlement Period following delivery of the Notice of Exercise. The Company agrees to maintain a transfer agent that is a participant in the FAST program so long as this Warrant remains outstanding and exercisable. As used herein, “ Standard Settlement Period ” means the standard settlement period, expressed in a number of Trading Days, on the Company’s primary Trading Market with respect to the Common Stock as in effect on the date of delivery of the Notice of Exercise.

pay the Holder $1,000. The Holder shall provide the Company written notice indicating the amounts payable to the Holder in respect of the Buy-In and, upon request of the Company, evidence of the amount of such loss. Nothing herein shall limit a Holder’s right to pursue any other remedies available to it hereunder, at law or in equity including, without limitation, a decree of specific performance and/or injunctive relief with respect to the Company’s failure to timely deliver shares of Common Stock upon exercise of the Warrant as required pursuant to the terms hereof.

v. No Fractional Shares or Scrip . No fractional shares or scrip representing fractional shares shall be issued upon the exercise of this Warrant. As to any fraction of a share which the Holder would otherwise be entitled to purchase upon such exercise, the Company shall, at its election, either pay a cash adjustment in respect of such final fraction in an amount equal to such fraction multiplied by the Exercise Price or round up to the next whole share.

vii. Closing of Books . The Company will not close its stockholder books or records in any manner which prevents the timely exercise of this Warrant, pursuant to the terms hereof.

be the Holder’s determination of whether this Warrant is exercisable (in relation to other securities owned by the Holder together with any Affiliates and Attribution Parties) and of which portion of this Warrant is exercisable, in each case subject to the Beneficial Ownership Limitation, and the Company shall have no obligation to verify or confirm the accuracy of such determination. In addition, a determination as to any group status as contemplated above shall be determined in accordance with Section 13(d) of the Exchange Act and the rules and regulations promulgated thereunder. For purposes of this Section 2(e), in determining the number of outstanding shares of Common Stock, a Holder may rely on the number of outstanding shares of Common Stock as reflected in (A) the Company’s most recent periodic or annual report filed with the Commission, as the case may be, (B) a more recent public announcement by the Company or (C) a more recent written notice by the Company or the Transfer Agent setting forth the number of shares of Common Stock outstanding. Upon the written or oral request of a Holder, the Company shall within two (2) Trading Days confirm orally and in writing to the Holder the number of shares of Common Stock then outstanding. In any case, the number of outstanding shares of Common Stock shall be determined after giving effect to the conversion or exercise of securities of the Company, including this Warrant, by the Holder or its Affiliates or Attribution Parties since the date as of which such number of outstanding shares of Common Stock was reported. The “ Beneficial Ownership Limitation ” shall be 4.99% of the number of shares of the Common Stock outstanding immediately after giving effect to the issuance of shares of Common Stock issuable upon exercise of this Warrant. The Holder, upon notice to the Company, may increase or decrease the Beneficial Ownership Limitation provisions of this Section 2(e), provided that the Beneficial Ownership Limitation in no event exceeds 9.99% of the number of shares of the Common Stock outstanding immediately after giving effect to the issuance of shares of Common Stock upon exercise of this Warrant held by the Holder and the provisions of this Section 2(e) shall continue to apply. Any increase in the Beneficial Ownership Limitation will not be effective until the 61 st day after such notice is delivered to the Company. The provisions of this paragraph shall be construed and implemented in a manner otherwise than in strict conformity with the terms of this Section 2(e) to correct this paragraph (or any portion hereof) which may be defective or inconsistent with the intended Beneficial Ownership Limitation herein contained or to make changes or supplements necessary or desirable to properly give effect to such limitation. The limitations contained in this paragraph shall apply to a successor holder of this Warrant.

Section 3 . Certain Adjustments .

Ownership Limitation) immediately before the date on which a record is taken for the grant, issuance or sale of such Purchase Rights, or, if no such record is taken, the date as of which the record holders of shares of Common Stock are to be determined for the grant, issue or sale of such Purchase Rights (provided, however, to the extent that the Holder’s right to participate in any such Purchase Right would result in the Holder exceeding the Beneficial Ownership Limitation, then the Holder shall not be entitled to participate in such Purchase Right to such extent (or beneficial ownership of such shares of Common Stock as a result of such Purchase Right to such extent) and such Purchase Right to such extent shall be held in abeyance for the Holder until such time, if ever, as its right thereto would not result in the Holder exceeding the Beneficial Ownership Limitation).

(c) Pro Rata Distributions . During such time as this Warrant is outstanding, if the Company shall declare or make any dividend (other than cash) or other distribution of its assets (or rights to acquire its assets) to holders of shares of Common Stock other than as set forth in Section 3(a), by way of return of capital or otherwise (including, without limitation, any distribution of stock or other securities, property or options by way of a dividend, spin off, reclassification, corporate rearrangement, scheme of arrangement or other similar transaction) (a “ Distribution ”), at any time after the issuance of this Warrant, then, in each such case, the Holder shall be entitled to participate in such Distribution to the same extent that the Holder would have participated therein if the Holder had held the number of shares of Common Stock acquirable upon complete exercise of this Warrant (without regard to any limitations on exercise hereof, including without limitation, the Beneficial Ownership Limitation) immediately before the date of which a record is taken for such Distribution, or, if no such record is taken, the date as of which the record holders of shares of Common Stock are to be determined for the participation in such Distribution ( provided , however , to the extent that the Holder’s right to participate in any such Distribution would result in the Holder exceeding the Beneficial Ownership Limitation, then the Holder shall not be entitled to participate in such Distribution to such extent (or in the beneficial ownership of any shares of Common Stock as a result of such Distribution to such extent) and the portion of such Distribution shall be held in abeyance for the benefit of the Holder until such time, if ever, as its right thereto would not result in the Holder exceeding the Beneficial Ownership Limitation).

Consideration issuable in respect of one share of Common Stock in such Fundamental Transaction, and the Company shall apportion the Exercise Price among the Alternate Consideration in a reasonable manner reflecting the relative value of any different components of the Alternate Consideration. If holders of Common Stock are given any choice as to the securities, cash or property to be received in a Fundamental Transaction, then the Holder shall be given the same choice as to the Alternate Consideration it receives upon any exercise of this Warrant following such Fundamental Transaction. The Company shall cause any successor entity in a Fundamental Transaction in which the Company is not the survivor (the “ Successor Entity ”) to assume in writing all of the obligations of the Company under this Warrant in accordance with the provisions of this Section 3(d) pursuant to written agreements in form and substance reasonably satisfactory to the Holder and approved by the Holder (without unreasonable delay) prior to such Fundamental Transaction and shall, at the option of the Holder, deliver to the Holder in exchange for this Warrant a security of the Successor Entity evidenced by a written instrument substantially similar in form and substance to this Warrant which is exercisable for a corresponding number of shares of capital stock of such Successor Entity (or its parent entity) equivalent to the shares of Common Stock acquirable and receivable upon exercise of this Warrant (without regard to any limitations on the exercise of this Warrant) prior to such Fundamental Transaction, and with an Exercise price which applies the Exercise price hereunder to such shares of capital stock (but taking into account the relative value of the shares of Common Stock pursuant to such Fundamental Transaction and the value of such shares of capital stock, such number of shares of capital stock and such exercise price being for the purpose of protecting the economic value of this Warrant immediately prior to the consummation of such Fundamental Transaction), and which is reasonably satisfactory in form and substance to the Holder. Upon the occurrence of any such Fundamental Transaction, the Successor Entity shall succeed to, and be substituted for (so that from and after the date of such Fundamental Transaction, the provisions of this Warrant referring to the “Company” shall refer instead to the Successor Entity), and may exercise every right and power of the Company and shall assume all of the obligations of the Company under this Warrant with the same effect as if such Successor Entity had been named as the Company herein.

(f) Notice to Holder .

redemption, rights or warrants, or if a record is not to be taken, the date as of which the holders of the Common Stock of record to be entitled to such dividend, distributions, redemption, rights or warrants are to be determined or (y) the date on which such reclassification, consolidation, liquidation, merger, sale, transfer or share exchange is expected to become effective or close, and the date as of which it is expected that holders of the Common Stock of record shall be entitled to exchange their shares of the Common Stock for securities, cash or other property deliverable upon such reclassification, consolidation, liquidation, merger, sale, transfer or share exchange; provided that the failure to deliver such notice or any defect therein or in the delivery thereof shall not affect the validity of the corporate action required to be specified in such notice. Nothing in this Warrant shall be construed as to require the Company to deliver a notice to the Holder which constitutes or contains material, non-public information regarding the Company or any subsidiaries. The Holder shall remain entitled to exercise this Warrant during the period commencing on the date of such notice to the effective date of the event triggering such notice except as may otherwise be expressly set forth herein.

Section 4 . Transfer of Warrant .

(a) Transferability . Pursuant to FINRA Rule 5110(g)(1), neither this Warrant nor any Warrant Shares issued upon exercise of this Warrant shall be sold, transferred, assigned, pledged or hypothecated, or be the subject of any hedging, short sale, derivative, put or call transaction that would result in the effective economic disposition of the securities by any person for a period of 180 days immediately following the date of effectiveness or commencement of sales of the offering pursuant to which this Warrant is being issued, except the transfer of any security:

i. by operation of law or by reason of reorganization of the Company;

ii. to any FINRA member firm participating in the offering and the officers and partners thereof, if all securities so transferred remain subject to the lock-up restriction in this Section 4(a) for the remainder of the time period;

iii. if the aggregate amount of securities of the Company held by the underwriter and related persons do not exceed 1% of the securities being offered;

iv. that is beneficially owned on a pro-rata basis by all equity owners of an investment fund, provided that no participating member manages or otherwise directs investments by the fund, and participating members in the aggregate do not own more than 10% of the equity in the fund; or

v. the exercise or conversion of any security, if all securities received remain subject to the lock-up restriction in this Section 4(a) for the remainder of the time period.

Subject to the foregoing restriction and subject to compliance with any applicable securities laws and the conditions set forth in Section 4(d) hereof, this Warrant and all rights hereunder are transferable , this Warrant and all rights hereunder (including, without limitation, any registration rights) are transferable, in whole or in part, upon surrender of this Warrant at the principal office of the Company or its designated agent, together with a written assignment of this Warrant substantially in the form attached hereto duly executed by the Holder or its agent or attorney and funds sufficient to pay any transfer taxes payable upon the making of such transfer. Upon such surrender and, if required, such payment, the Company shall execute and deliver a new Warrant or Warrants in the name of the assignee or assignees, as applicable, and in the denomination or denominations specified in such instrument of assignment, and shall issue to the assignor a new Warrant evidencing the portion of this Warrant not so assigned, and this Warrant shall promptly be cancelled. Notwithstanding anything herein to the contrary, the Holder shall not be required to physically surrender this Warrant to the Company unless the Holder has assigned this Warrant in full, in which case, the Holder shall surrender this Warrant to the Company within two (2) Trading Days of the date on which the Holder delivers an assignment form to the Company assigning this Warrant in full. The Warrant, if properly assigned in accordance herewith, may be exercised by a new holder for the purchase of Warrant Shares without having a new Warrant issued.

(d) Transfer Restrictions . If, at the time of the surrender of this Warrant in connection with any transfer of this Warrant, the transfer of this Warrant shall not be either (i) registered pursuant to an effective registration statement under the Securities Act and under applicable state securities or blue sky laws or (ii) eligible for resale without volume or manner-of-sale restrictions or current public information requirements pursuant to Rule 144, the Company may require, as a condition of allowing such transfer, the transferor thereof to provide to the Company an opinion of counsel selected by the transferor and reasonably acceptable to the Company, the form and substance of which opinion shall be reasonably satisfactory to the Company, to the effect that such transfer does not require registration of this Warrant or Warrant Shares under the Securities Act. As a condition of transfer, any such transferee shall agree in writing to be bound by the terms of this Agreement and shall have the rights and obligations of a Holder under this Agreement.

e) Representation by the Holder . The Holder, by the acceptance hereof, represents and warrants that it is acquiring this Warrant and, upon any exercise hereof, will acquire the Warrant Shares issuable upon such exercise, for its own account and not with a view to or for distributing or reselling such Warrant Shares or any part thereof in violation of the Securities Act or any applicable state securities law, except pursuant to sales registered or exempted under the Securities Act.

Section 5 . Miscellaneous .

(d) Authorized Shares .

The Company covenants that during the period the Warrant is outstanding, it will reserve from its authorized and unissued Common Stock a sufficient number of shares to provide for the issuance of the

Warrant Shares upon the exercise of any purchase rights under this Warrant. The Company further covenants that its issuance of this Warrant shall constitute full authority to its officers who are charged with the duty of issuing the necessary Warrant Shares upon the exercise of the purchase rights under this Warrant. The Company will take all such reasonable action as may be necessary to assure that such Warrant Shares may be issued as provided herein without violation of any applicable law or regulation, or of any requirements of the Trading Market upon which the Common Stock may be listed. The Company covenants that all Warrant Shares which may be issued upon the exercise of the purchase rights represented by this Warrant will, upon exercise of the purchase rights represented by this Warrant and payment for such Warrant Shares in accordance herewith, be duly authorized, validly issued, fully paid and nonassessable and free from all taxes, liens and charges created by the Company in respect of the issue thereof (other than taxes in respect of any transfer occurring contemporaneously with such issue).

(l) Amendment . This Warrant may be modified or amended or the provisions hereof waived with the written consent of the Company and the Holder.

prohibition or invalidity, without invalidating the remainder of such provisions or the remaining provisions of this Warrant.

(n) Headings . The headings used in this Warrant are for the convenience of reference only and shall not, for any purpose, be deemed a part of this Warrant.

********************

(Signature Page Follows)

IN WITNESS WHEREOF, the Company has caused this Warrant to be executed by its officer thereunto duly authorized as of the date first above indicated.

	VAXART, INC.

	By:
		Name: Wouter W. Latour, M.D.
		Title: President and Chief Executive Officer

NOTICE OF EXERCISE

TO: VAXART, INC.

(2) Payment shall take the form of (check applicable box):

o in lawful money of the United States; or

(3) Please issue said Warrant Shares in the name of the undersigned or in such other name as is specified below:

The Warrant Shares shall be delivered to the following DWAC Account Number:

(4) The undersigned is an “accredited investor” as defined in Regulation D promulgated under the Securities Act of 1933, as amended.

[SIGNATURE OF HOLDER]

Name of Investing Entity:
Signature of Authorized Signatory of Investing Entity :
Name of Authorized Signatory:
Title of Authorized Signatory:
Date:

EXHIBIT B

ASSIGNMENT FORM

(To assign the foregoing Warrant, execute this form and supply required information. Do not use this form to purchase shares.)

FOR VALUE RECEIVED, the foregoing Warrant and all rights evidenced thereby are hereby assigned to

Name:
			(Please Print)

Address:
			(Please Print)

Phone Number:

Email Address:

Dated: ,

Holder’s Signature:

Holder’s Address:

Exhibit 5.1

John T. McKenna

+1 650 843 5059

jmckenna@cooley.com

April 8, 2019

Vaxart, Inc.

290 Utah Ave

Suite 200

South San Francisco, CA 94080

Ladies and Gentlemen:

We have acted as counsel to Vaxart, Inc., a Delaware corporation, (the “ Company ”), in connection with the filing of a registration statement (No. 333-229536) on Form S-1 (the “ Registration Statement ”) with the Securities and Exchange Commission, including a related prospectus filed with the Registration Statement (the “ Prospectus ”), covering an underwritten public offering of:

(i) up to an aggregate of 6,095,000 shares (the “ Shares ”) of common stock of the Company, par value $0.10 per share (the “ Common Stock ”);

(ii) pre-funded warrants to purchase up to an aggregate of 5,300,000 shares of Common Stock (the “ Pre-Funded Warrants ”) and the shares of Common Stock issuable upon exercise thereunder; and

(iii) warrants to purchase up to 6,095,000 shares of Common Stock (the “ Common Warrants ”) and the shares of Common Stock issuable upon exercise thereunder;

including additional Shares and Common Warrants that may be sold pursuant to the exercise of an option to purchase additional Shares and Common Warrants. The Registration Statement also covers the issuance of warrants to purchase up to 426,650 shares of Common Stock being issued to the underwriters of the offering (the “ Representative Warrants ”) and the shares of Common Stock issuable upon exercise thereunder. The Pre-Funded Warrants, the Common Warrants, and the Representative Warrants are collectively referred to herein as the “ Warrants ” and the shares of Common Stock issuable upon exercise of the Warrants are referred to as the “ Warrants Shares . ” The Shares, the Warrants and the Warrant Shares are to be issued by the Company as described in the Registration Statement and the Prospectus.

In connection with this opinion, we have examined and relied upon the Registration Statement and Prospectus, the form of Pre-Funded Warrant, the form of Common Warrant, the form of Representative Warrant, the Company’s Certificate of Incorporation, as amended, its Restated Bylaws and the originals or copies certified to our satisfaction of such records, documents, certificates, memoranda and other instruments as in our judgment are necessary or appropriate to enable us to render the opinion expressed below. We have assumed the genuineness and authenticity of all documents submitted to us as originals, and the conformity to originals of all documents submitted to us as copies thereof and the due execution and delivery of all documents by all persons other than the Company where due execution and delivery are a prerequisite to the effectiveness thereof. In addition, we have assumed that the Board of Directors of the Company or a pricing committee thereof has taken action to set the sale price of the Shares and Warrants and the exercise price of the Warrants.

With regard to our opinion regarding the Warrants and the Warrant Shares, we express no opinion to the extent that, notwithstanding its current reservation of shares of Common Stock, future issuances of securities, including the Warrant Shares, of the Company and/or antidilution adjustments to outstanding

Cooley LLP 3175 Hanover Street Palo Alto, CA 94304
t: (650) 843-5000 f: (650) 849-7400 cooley.com

Vaxart, Inc.

April 8, 2019

Page Two

securities, including the Warrants, of the Company cause the Warrants to be exercisable for more shares of Common Stock than the number that then remain authorized but unissued.

With regard to our opinion concerning the Warrants constituting valid and binding obligations of the Company:

(i) Our opinion is subject to, and may be limited by, (a) applicable bankruptcy, reorganization, insolvency, moratorium, fraudulent conveyance, debtor and creditor, and similar laws which relate to or affect creditors’ rights generally, and (b) general principles of equity (including, without limitation, concepts of materiality, reasonableness, good faith and fair dealing) regardless of whether considered in a proceeding in equity or at law.

(ii) Our opinion is subject to the qualification that the availability of specific performance, an injunction or other equitable remedies is subject to the discretion of the court before which the request is brought.

(iii) We express no opinion as to any provision of the Warrants that: (a) provides for liquidated damages, buy-in damages, monetary penalties, prepayment or make-whole payments or other economic remedies to the extent such provisions may constitute unlawful penalties, (b) relates to advance waivers of claims, defenses, rights granted by law, or notice, opportunity for hearing, evidentiary requirements, statutes of limitations, trial by jury, or procedural rights, (c) restricts non-written modifications and waivers, (d) provides for the payment of legal and other professional fees where such payment is contrary to law or public policy, (e) relates to exclusivity, election or accumulation of rights or remedies, (f) authorizes or validates conclusive or discretionary determinations, or (g) provides that provisions of the Warrants are severable to the extent an essential part of the agreed exchange is determined to be invalid and unenforceable.

(iv) We express no opinion as to whether a state court outside of the State of New York or a federal court of the United States would give effect to the choice of New York law or jurisdiction provided for in the Warrants.

Our opinion herein is expressed solely with respect to the General Corporation Law of the State of Delaware and, as to the Warrants constituting valid and legally binding obligations of the Company, the laws of the State of New York. Our opinion is based on these laws as in effect on the date hereof. We express no opinion to the extent that any other laws are applicable to the subject matter hereof and express no opinion and provide no assurance as to compliance with any federal or state securities law, rule or regulation.

On the basis of the foregoing, and in reliance thereon, we are of the opinion that (i) the Shares, when sold in accordance with the Registration Statement and the Prospectus, will be validly issued, fully paid and nonassessable, (ii) provided that the Warrants have been duly executed and delivered by the Company to the purchasers thereof against payment therefor, the Warrants, when issued and sold as provided in the Registration Statement and the Prospectus will be valid and legally binding obligations of the Company, and (iii) the Warrant Shares, when issued and paid for in accordance with the terms of the Warrants, will be validly issued, fully paid and non-assessable.

Vaxart, Inc.

April 8, 2019

Page Three

We consent to the reference to our firm under the caption “Legal Matters” in the Prospectus included in the Registration Statement and to the filing of this opinion as an exhibit to the Registration Statement. This opinion is expressed as of the date hereof, and we disclaim any undertaking to advise you of any subsequent changes in the facts stated or assumed herein or of any subsequent changes in applicable law.

Sincerely,

Cooley LLP


By:	/s/ John T. McKenna
	John T. McKenna

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Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

The Board of Directors
Vaxart, Inc.:

We consent to the use of our report dated February 6, 2019, with respect to the consolidated balance sheets of Vaxart, Inc. as of December 31, 2018 and 2017, the related consolidated statements of operations and comprehensive loss, stockholders' equity (deficit), and cash flows for each of the years in the two-year period ended December 31, 2018, and the related notes (collectively, the "consolidated financial statements"), incorporated herein by reference and to the reference to our firm under the heading "Experts" in the prospectus.

Our report dated February 6, 2019 contains an explanatory paragraph that states that the Company has experienced losses and negative cash flows from operations since its inception, has an accumulated deficit, and has debt obligations which raise substantial doubt about its ability to continue as a going concern. The consolidated financial statements do not include any adjustments that might result from the outcome of that uncertainty.

/s/ KPMG LLP

San Francisco, California
April 7, 2019

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Exhibit 23.1

Consent of Independent Registered Public Accounting Firm