Vaxart, Inc. (Form: S-3, Received: 12/20/2018 06:04:27)

As filed with the U.S. Securities and Exchange Commission on December 19, 2018

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

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FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

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VAXART, INC.

(Exact name of registrant as specified in its charter)

Delaware

59-1212264

(State or other jurisdiction of

incorporation or organization)

(I.R.S. Employer

Identification Number)

_____________________

290 Utah Ave

Suite 200

South San Francisco, CA 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, CA 94080

(Name, address, including zip code, and telephone number, including area code, of agent for service)

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Copies to:

John T. McKenna

Josh Seidenfeld

Cooley LLP

3175 Hanover Street

Palo Alto, California 94304

(650) 843-5000

Approximate date of commencement of proposed sale to the public: From time to time after the effective date of this Registration Statement.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box: o

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, other than securities offered only in connection with dividend or interest reinvestment plans, 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, 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 registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. o

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. 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. o

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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 (2)	$25,000,000	$3,030

(1) The proposed maximum aggregate offering price has been calculated pursuant to Rule 457(o) under the Securities Act.

(2) There are being registered hereunder such indeterminate number of shares of common stock to be sold by the Registrant from time to time at unspecified prices which shall have an aggregate initial offering price not to exceed $25,000,000. The proposed maximum offering price per share will be determined, from time to time, by the Registrant in connection with the issuance by the Registrant of the securities registered hereunder.

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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.

EXPLANATORY NOTE

This registration statement contains two prospectuses:

• a base prospectus which covers the offering, issuance and sale by Vaxart of up to a maximum aggregate offering price of $25,000,000 of Vaxart’s common stock; and

• a sales agreement prospectus covering the offering, issuance and sale by Vaxart of up to a maximum aggregate offering price of $4,250,000 of Vaxart’s common stock that may be issued and sold under a sales agreement with B. Riley FBR, Inc.

The base prospectus immediately follows this explanatory note. The prospectus relating to the sales agreement immediately follows the base prospectus. The common stock that may be offered, issued and sold by Vaxart under the sales agreement prospectus is included in the $25,000,000 of securities that may be offered, issued and sold by Vaxart under the base prospectus. Upon termination of the sales agreement with B. Riley FBR, Inc., any portion of the $4,250,000 included in the sales agreement prospectus that is not sold pursuant to the sales agreement will be available for sale in other offerings pursuant to the base prospectus and a corresponding prospectus supplement, and if no shares are sold under the sales agreement, the full $25,000,000 of securities may be sold in other offerings pursuant to the base prospectus.

The information in this 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 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.

SUBJECT TO COMPLETION, DATED DECEMBER 19, 2018

PROSPECTUS

$25,000,000

Common Stock

From time to time, we may offer and sell up to an aggregate amount of $25,000,000 of common stock.

We will provide the specific terms of these offerings in one or more supplements to this prospectus. We may also authorize one or more free writing prospectuses to be provided to you in connection with these offerings. The prospectus supplement and any related free writing prospectus may also add, update or change information contained in this prospectus. You should carefully read this prospectus, the applicable prospectus supplement and any related free writing prospectus, as well as any documents incorporated by reference, before buying any of the shares of common stock being offered.

Our common stock is listed on the Nasdaq Capital Market under the trading symbol “VXRT.” On December 18, 2018, the last reported sale price of our common stock was $2.40 per share. The applicable prospectus supplement will contain information, where applicable, as to other listings, if any, on the Nasdaq Capital Market or other securities exchange of the shares of common stock covered by the applicable prospectus supplement.

Investing in shares of our common stock involves a high degree of risk. You should review carefully the risks and uncertainties described in the section titled “Risk Factors” on page 3 of this prospectus and any similar section contained in the applicable prospectus supplement and in any free writing prospectuses we have authorized for use in connection with a specific offering, and under similar headings in the documents that are incorporated by reference into this prospectus.

This prospectus may not be used to consummate a sale of shares of our common stock unless accompanied by a prospectus supplement.

As of December 19, 2018, the aggregate market value of our outstanding common stock held by non-affiliates, or public float, was $12,869,577, which was calculated based on 4,021,743 shares of outstanding common stock held by non-affiliates at a price of $3.20 per share, which was the closing price of our common stock on the Nasdaq Capital Market on November 28, 2018. Pursuant to General Instruction I.B.6 of Form S-3, in no event will we sell securities registered on the registration statement of which this prospectus is a part in a public primary offering with a value exceeding more than one-third of our public float in any 12-month period so long as our public float remains below $75.0 million. As of the date hereof, we have not offered any securities pursuant to General Instruction I.B.6 of Form S-3 during the 12 calendar months prior to and including the date of this prospectus.

The shares of our common stock may be sold directly by us to investors, through agents designated from time to time or to or through underwriters or dealers, on a continuous or delayed basis. For additional information on the methods of sale, you should refer to the section titled “Plan of Distribution” in this prospectus. If any agents or underwriters are involved in the sale of any shares of our common stock with respect to which this prospectus is being delivered, the names of such agents or underwriters and any applicable fees, commissions, discounts and over-allotment options will be set forth in a prospectus supplement. The price to the public of such shares of our common stock and the net proceeds we expect to receive from such sale will also be set forth in a prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

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The date of this prospectus is , 2018.

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ABOUT THIS PROSPECTUS		i
PROSPECTUS SUMMARY		1
RISK FACTORS		3
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS		4
USE OF PROCEEDS		6
DESCRIPTION OF CAPITAL STOCK		7
PLAN OF DISTRIBUTION		10
LEGAL MATTERS		12
EXPERTS		12
WHERE YOU CAN FIND ADDITIONAL INFORMATION		13
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE		14

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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission, or the SEC, using a “shelf” registration process. Under this shelf registration statement, we may, from time to time, offer and sell in one or more offerings, up to a total dollar amount of $25,000,000 of shares of our common stock as described in this prospectus.

Each time we offer shares of our common stock under this prospectus, we will provide a prospectus supplement that will contain more specific information about the terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. The prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change any of the information contained in this prospectus or in the documents that we have incorporated by reference into this prospectus. We urge you to read carefully this prospectus, any applicable prospectus supplement and any free writing prospectuses we have authorized for use in connection with a specific offering, together with the information incorporated herein by reference as described under the heading “Incorporation of Certain Information by Reference,” before buying any of the shares of our common stock being offered.

This prospectus may not be used to consummate a sale of shares of our common stock unless it is accompanied by a prospectus supplement.

You should rely only on the information contained in, or incorporated by reference into, this prospectus and any applicable prospectus supplement, along with the information contained in any free writing prospectuses we have authorized for use in connection with a specific offering. We have not authorized anyone to provide you with any information other than that contained or incorporated by reference in this prospectus and any applicable prospectus supplement, along with the information contained in any free writing prospectuses we have authorized for use in connection with a specific offering. You must not rely upon any information or representation not contained or incorporated by reference in this prospectus, the accompanying prospectus supplement or in any related free writing prospectus that we may authorize to be provided to 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 of our common stock offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so.

The information appearing in this prospectus, any applicable prospectus supplement or any related free writing prospectus is accurate only as of the date on the front of the document and that any information we have incorporated by reference is accurate only as of the date of the document incorporated by reference, regardless of the time of delivery of this prospectus, any applicable prospectus supplement or any related free writing prospectus, or any sale of shares of our common stock. Our business, financial condition, results of operations and prospects may have changed since those dates.

This prospectus contains and incorporates by reference 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 in this prospectus and the documents incorporated herein by reference, these estimates involve risks and uncertainties and are subject to change based on various factors, including those discussed in the section titled “Risk Factors” contained in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus. Accordingly, investors should not place undue reliance on this information.

This prospectus contains summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed, will be filed or will be incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described below under the section titled “Where You Can Find Additional Information.”

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PROSPECTUS SUMMARY

This summary highlights selected information contained elsewhere in this prospectus or incorporated by reference in this prospectus, and does not contain all of the information that you need to consider in making your investment decision. You should carefully read the entire prospectus, the applicable prospectus supplement and any related free writing prospectus, including the risks of investing in our shares of our common stock discussed in the section titled “Risk Factors” contained in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus. You should also carefully read the other information incorporated by reference into this prospectus, including our financial statements, and the exhibits to the registration statement of which this prospectus is a part.

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

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.

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.”

The Shares of Common Stock We May Offer

We may offer shares of our common stock up to a total dollar amount of $25,000,000, from time to time under this prospectus, together with the applicable prospectus supplement and any related free writing prospectus, at prices and on terms to be determined by market conditions at the time of any offering. Each time we offer shares of our common stock under this prospectus, we will provide a prospectus supplement that will describe the specific amounts, prices and other important terms of the offering.

The applicable prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change any of the information contained in this prospectus or in the documents we have incorporated by reference. However, no prospectus supplement or free writing prospectus will offer any security other than shares of our common stock.

THIS PROSPECTUS MAY NOT BE USED TO CONSUMMATE A SALE OF SHARES OF OUR COMMON STOCK UNLESS IT IS ACCOMPANIED BY A PROSPECTUS SUPPLEMENT.

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We may sell the shares of our common stock directly to investors or to or through agents, underwriters or dealers. We and our agents or underwriters, reserve the right to accept or reject all or part of any proposed purchase of shares of our common stock. If we do offer shares of our common stock to or through agents or underwriters, we will include in the applicable prospectus supplement:

•         the names of those agents or underwriters;

•         applicable fees, discounts and commissions to be paid to them;

•         details regarding over-allotment options, if any; and

•         the net proceeds to us.

We may issue shares of our common stock from time to time. The holders of our common stock are entitled to one vote for each share held of record on all matters submitted to a vote of stockholders. Subject to preferences that may be applicable to any outstanding shares of preferred stock, the holders of common stock are entitled to receive ratably such dividends as may be declared by our board of directors out of legally available funds. Upon our liquidation, dissolution or winding up, holders of our common stock are entitled to share ratably in all assets remaining after payment of liabilities and the liquidation preferences of any outstanding shares of preferred stock. Holders of common stock have no preemptive rights and no right to convert their common stock into any other securities. There are no redemption or sinking fund provisions applicable to our common stock. We urge you to read the applicable prospectus supplement (and any related free writing prospectus that we may authorize to be provided to you) related to any common stock being offered.

Use of Proceeds

Except as described in any applicable prospectus supplement or in any free writing prospectuses we have authorized for use in connection with a specific offering, we currently intend to use the net proceeds from the sale of the securities offered by us hereunder 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. See the section titled “Use of Proceeds” in this prospectus.

Nasdaq Capital Market Listing

Our common stock is listed on the Nasdaq Capital Market under the symbol “VXRT.” The applicable prospectus supplement will contain information, where applicable, as to other listings, if any, on the Nasdaq Capital Market or other securities exchange of the shares of our common stock covered by the applicable prospectus supplement.

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RISK FACTORS

Investing in shares of our common stock involves a high degree of risk. Before deciding whether to invest in shares of our common stock, you should consider carefully the risks and uncertainties described in the section titled “Risk Factors” contained in the applicable prospectus supplement and any related free writing prospectus, and discussed under the section titled “Risk Factors” contained in our most recent Annual Report on Form 10-K and in our most recent Quarterly Report on Form 10-Q, as well as any amendments thereto reflected in subsequent filings with the SEC, which are incorporated by reference into this prospectus in their entirety, together with other information in this prospectus, the documents incorporated by reference and any free writing prospectus that we may authorize for use in connection with this offering. The risks described in these documents are not the only ones we face, but those that we consider to be material. There may be other unknown or unpredictable economic, business, competitive, regulatory or other factors that could have material adverse effects on our future results. Past financial performance may not be a reliable indicator of future performance, and historical trends should not be used to anticipate results or trends in future periods. If any of these risks actually occurs, our business, financial condition, results of operations or cash flow could be harmed. This could cause the trading price of our common stock to decline, resulting in a loss of all or part of your investment. Please also read carefully the section below titled “Special Note Regarding Forward-Looking Statements.”

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and the documents we have filed with 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; and

• developments and projections relating to our competitors or our industry.

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” contained in the applicable prospectus supplement, in any free writing prospectuses we may authorize for use in connection with a specific offering, and in our most recent Annual Report on Form 10-K and in our most recent Quarterly Report on Form 10-Q, 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.

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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 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, any applicable prospectus supplement, 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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USE OF PROCEEDS

Except as described in any applicable prospectus supplement or in any free writing prospectuses we have authorized for use in connection with a specific offering, we currently intend to use the net proceeds from the sale of the securities offered by us hereunder 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 .

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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. As of September 30, 2018, there were 7,141,189 shares of common stock issued and outstanding, and no shares of preferred stock outstanding.

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 in the election of directors each stockholder has cumulative voting rights and is entitled to a number of votes equal to the number of shares held by such stockholder multiplied by the number of directors to be elected, and each stockholder may cast all of such votes for a single director or may distribute them among the number to be voted for, or for any two or more of them as the stockholder may see fit.

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 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.

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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 September 30, 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;

• 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:

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• 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 and not be 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;

• provide that special meetings of our stockholders may be called only by the chairman of the board, our Chief Executive Officer, 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); and

• provide that the Court of Chancery of the State of Delaware will be the sole and exclusive forum for (i) any derivative action or proceeding brought on our behalf, (ii) any action asserting a claim of breach of a fiduciary duty owed by any of our directors or officers to our or its stockholders, (iii) any action asserting a claim against us arising pursuant to any provision of the DGCL or our certificate of incorporation or bylaws, (iv) any action to interpret, apply, enforce or determine the validity of our certificate of incorporation or bylaws or (v) any action asserting a claim against us governed by the internal affairs doctrine.

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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PLAN OF DISTRIBUTION

We may sell the shares of our common stock from time to time pursuant to underwritten public offerings, direct sales to the public, negotiated transactions, block trades or a combination of these methods. We may sell the shares of our common stock to or through underwriters or dealers, through agents, or directly to one or more purchasers. We may distribute the shares from time to time in one or more transactions:

• at a fixed price or prices, which may be changed;

• at market prices prevailing at the time of sale;

• at prices related to such prevailing market prices; or

• at negotiated prices.

A prospectus supplement or supplements (and any related free writing prospectus that we may authorize to be provided to you) will describe the terms of the offering of the shares of our common stock, including, to the extent applicable:

• the name or names of the underwriters, if any;

• the purchase price of the shares of our common stock or other consideration therefor, and the proceeds, if any, we will receive from the sale;

• any over-allotment options under which underwriters may purchase additional shares of our common stock from us;

• any agency fees or underwriting discounts and other items constituting agents’ or underwriters’ compensation;

• any public offering price;

• any discounts or concessions allowed or reallowed or paid to dealers; and

• any securities exchange or market on which the shares of our common stock may be listed.

Only underwriters named in the prospectus supplement will be underwriters of the shares of our common stock offered by the prospectus supplement.

If underwriters are used in the sale, they will acquire the shares of our common stock for their own account and may resell the shares of our common stock from time to time in one or more transactions at a fixed public offering price or at varying prices determined at the time of sale. The obligations of the underwriters to purchase the shares of our common stock will be subject to the conditions set forth in the applicable underwriting agreement. We may offer the shares of our common stock to the public through underwriting syndicates represented by managing underwriters or by underwriters without a syndicate. Subject to certain conditions, the underwriters will be obligated to purchase all of the shares of our common stock offered by the prospectus supplement, other than shares of our common stock covered by any over-allotment option. Any public offering price and any discounts or concessions allowed or reallowed or paid to dealers may change from time to time. We may use underwriters with whom we have a material relationship. We will describe in the prospectus supplement, naming the underwriter, the nature of any such relationship.

We may sell shares of our common stock directly or through agents we designate from time to time. We will name any agent involved in the offering and sale of shares of our common stock and we will describe any commissions we will pay the agent in the prospectus supplement. Unless the prospectus supplement states otherwise, our agent will act on a best-efforts basis for the period of its appointment.

We may authorize agents or underwriters to solicit offers by certain types of institutional investors to purchase shares of our common stock from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. We will describe the conditions to these contracts and the commissions we must pay for solicitation of these contracts in the prospectus supplement.

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We may provide agents and underwriters with indemnification against civil liabilities, including liabilities under the Securities Act, or contribution with respect to payments that the agents or underwriters may make with respect to these liabilities. Agents and underwriters may engage in transactions with, or perform services for us in the ordinary course of business.

Any underwriter may engage in over-allotment, stabilizing transactions, short-covering transactions and penalty bids in accordance with Regulation M under the Exchange Act. Over-allotment involves sales in excess of the offering size, which create a short position. Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum price. Syndicate-covering or other short-covering transactions involve purchases of the shares of our common stock, either through exercise of the over-allotment option or in the open market after the distribution is completed, to cover short positions. Penalty bids permit the underwriters to reclaim a selling concession from a dealer when the shares of our common stock originally sold by the dealer are purchased in a stabilizing or covering transaction to cover short positions. Those activities may cause the price of the shares of our common stock to be higher than it would otherwise be. If commenced, the underwriters may discontinue any of the activities at any time.

Any underwriters or agents that are qualified market makers on the Nasdaq Capital Market may engage in passive market making transactions in the common stock on the Nasdaq Capital Market in accordance with Regulation M under the Exchange Act, during the business day prior to the pricing of the offering, before the commencement of offers or sales of the common stock. Passive market makers must comply with applicable volume and price limitations and must be identified as passive market makers. In general, a passive market maker must display its bid at a price not in excess of the highest independent bid for such security; if all independent bids are lowered below the passive market maker’s bid, however, the passive market maker’s bid must then be lowered when certain purchase limits are exceeded. Passive market making may stabilize the market price of the shares of our common stock at a level above that which might otherwise prevail in the open market and, if commenced, may be discontinued at any time.

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LEGAL MATTERS

Cooley LLP, Palo Alto, California, will pass upon the validity of the shares of common stock offered hereby. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we name in the applicable prospectus supplement.

EXPERTS

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.

The consolidated financial statements of Aviragen Therapeutics, Inc. appearing in Aviragen Therapeutics, Inc.’s Annual Report on Form 10-K for the year ended June 30, 2017 have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their report thereon included therein, and incorporated herein by reference. Such financial statements are incorporated herein in reliance upon the report of Ernst & Young LLP pertaining to such financial statements (to the extent covered by consents filed with the Securities and Exchange Commission) given on the authority of such firm as experts in accounting and auditing.

The financial statements of Vaxart Biosciences, Inc. as of December 31, 2017 and 2016, and for each of the years in the two-year period ended December 31, 2017, have been incorporated by reference herein and in the registration statement 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, 2017 financial statements contains an explanatory paragraph that states that Vaxart Biosciences, Inc. has suffered recurring losses from operations, has an accumulated deficit, and has debt obligations which raise substantial doubt about its ability to continue as a going concern. The financial statements do not include any adjustments that might result from the outcome of that uncertainty.

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, t he 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 ADDITIONAL INFORMATION

This prospectus is part of the registration statement on Form S-3 we filed with the SEC under the Securities Act and does not contain all the information set forth in the registration statement. Whenever a reference is made in this prospectus to any of our contracts, agreements or other documents, the reference may not be complete and you should refer to the exhibits that are a part of the registration statement or the exhibits to the reports or other documents incorporated by reference into this prospectus for a copy of such contract, agreement or other document. Because we are subject to the information and reporting requirements of the Exchange Act, we file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s website at http://www.sec.gov.

We maintain a website at www.vaxart.com. Information contained in or accessible through our website does not constitute a 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):

• Aviragen’s Annual Report on Form 10-K, as amended by Form 10-K/A, for the year ended June 30, 2017, filed with the SEC on September 1, 2017, and October 20, 2017, respectively;

• Aviragen’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2017, filed with the SEC on November 7, 2017;

• Aviragen’s Quarterly Report on Form 10-Q for the quarter ended December 31, 2017, filed with the SEC on February 6, 2018;

• the information specifically incorporated by reference into Aviragen’s Annual Report on Form 10-K for the year ended June 30, 2017, from our definitive proxy statement relating to our 2018 annual meeting of stockholders, filed with the SEC on February 22, 2018;

• Vaxart’s Current Report on Form 8-K/A, filed with the SEC on April 2, 2018, which contains the audited financial statements of Private Vaxart for the years ended December 31, 2016 and 2017;

• Vaxart’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2018, filed with the SEC on May 15, 2018;

• Vaxart’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2018, filed with the SEC on August 10, 2018;

• Vaxart’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2018, filed with the SEC on November 13, 2018;

• our Current Reports on Form 8-K and Form 8-K/A (other than information furnished rather than filed) filed with the SEC on September 20, 2017, September 27, 2017, October 30, 2017 (excluding information furnished under Item 7.01) , October 31, 2017, November 30, 2017, December 19, 2017, January 5, 2018, January 12, 2018, January 17, 2018, January 24, 2018, January 26, 2018, February 1, 2018, February 6, 2018, February 7, 2018, February 9, 2018, February 20, 2018, April 13, 2018, April 27, 2018, June 6, 2018, June 8, 2018, November 20, 2018 and December 18, 2018; 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 .

All filings filed by us pursuant to the Exchange Act after the date of the initial filing of the registration statement of which this prospectus is a part and prior to effectiveness of the registration statement shall be deemed to be incorporated by reference into this prospectus.

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, including those made after the date of the initial filing of the registration statement of which this prospectus is a part and prior to effectiveness of such registration statement, until we file a post-effective amendment that indicates 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.

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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, CA 94080

Attn: Secretary

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SUBJECT TO COMPLETION, DATED DECEMBER 19, 2018

PROSPECTUS

$4,250,000

Common Stock

_____________________

We have entered into a Sales Agreement, or the Sales Agreement, with B. Riley FBR, Inc., or B. Riley FBR, dated December 19, 2018 , relating to shares of our common stock, par value $0.10 per share, offered by this prospectus. In accordance with the terms of the sales agreement, we may offer and sell shares of our common stock having an aggregate offering price of up to $4,250,000 from time to time through B. Riley FBR, acting as agent.

Our common stock is listed on the Nasdaq Capital Market under the symbol “VXRT.” On December 18, 2018, the last reported sale price of our common stock on the Nasdaq Capital Market was $2.40 per share.

Sales of our common stock, if any, under this prospectus supplement and the accompanying prospectus will be made in sales deemed to be “at the market offerings” as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, or the Securities Act. B. Riley FBR is not required to sell any specific amount of securities, but will act as our sales agent using commercially reasonable efforts consistent with its normal trading and sales practices, on mutually agreed terms between B. Riley FBR and us. There is no arrangement for funds to be received in any escrow, trust or similar arrangement.

As of December 19, 2018, the aggregate market value of our outstanding common stock held by non-affiliates, or public float, was $12,869,577, which was calculated based on 4,021,743 shares of outstanding common stock held by non-affiliates at a price of $3.20 per share, which was the closing price of our common stock on the Nasdaq Capital Market on November 28, 2018.Pursuant to General Instruction I.B.6 of Form S-3, in no event will we sell securities registered on the registration statement of which this prospectus is a part in a public primary offering with a value exceeding more than one-third of our public float in any 12-month period so long as our public float remains below $75.0 million. As of the date hereof, we have not offered any securities pursuant to General Instruction I.B.6 of Form S-3 during the 12 calendar months prior to and including the date of this prospectus.

B. Riley FBR will be entitled to compensation under the terms of the Sales Agreement at a fixed commission a rate of 3.0% of the gross sales price per share sold. In connection with the sale of the common stock on our behalf, B. Riley FBR will be deemed to be an “underwriter” within the meaning of the Securities Act and the compensation of B. Riley FBR will be deemed to be underwriting commissions or discounts. We have also agreed to provide indemnification and contribution to B. Riley FBR with respect to certain liabilities, including liabilities under the Securities Act or the Securities Exchange Act of 1934, as amended.

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Investing in our securities involves a high degree of risk. Before making an investment decision, please read the information in the section titled “Risk Factors” beginning on page S-3 of this prospectus and in the documents incorporated by reference into this prospectus.

B. Riley FBR

The date of this prospectus is , 2018

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ABOUT THIS PROSPECTUS		S-i
PROSPECTUS SUMMARY		S-1
THE OFFERING		S-2
RISK FACTORS		S-3
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS		S-5
USE OF PROCEEDS		S-7
DILUTION		S-8
DESCRIPTION OF CAPITAL STOCK		S-9
PLAN OF DISTRIBUTION		S-12
LEGAL MATTERS		S-13
EXPERTS		S-13
WHERE YOU CAN FIND ADDITIONAL INFORMATION		S-14
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE		S-15

_____________________

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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we have filed with the Securities and Exchange Commission, or the SEC, utilizing a “shelf” registration process. Under the shelf registration process, we may offer shares of our common stock having an aggregate offering price of up to $25,000,000. Under this prospectus, we may offer shares of our common stock having an aggregate offering price of up to $4,250,000 from time to time at prices and on terms to be determined by market conditions at the time of offering.

Before buying any of the common stock that we are offering, we urge you to carefully read this prospectus and all of the information incorporated by reference herein and therein, as well as the additional information described in the sections titled “Where You Can Find Additional Information” and “Incorporation of Certain Information by Reference.” These documents contain important information that you should consider when making your investment decision.

We provide information to you about this offering of shares of our common stock in this prospectus, which describes the specific details regarding this offering. If information in this prospectus is inconsistent with documents incorporated by reference in this prospectus filed prior to the date of this prospectus, you should rely on this prospectus. However, if any statement in one of these documents is inconsistent with a statement in another document having a later date-for example, a document incorporated by reference in this prospectus-the statement in the document having the later date modifies or supersedes the earlier statement as our business, financial condition, results of operations and prospects may have changed since the earlier dates.

You should rely only on the information contained in, or incorporated by reference into, this prospectus and in any free writing prospectus that we may authorize for use in connection with this offering. We have not, and B. Riley FBR has not, authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We and B. Riley FBR take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We are not, and B. Riley FBR is not, making an offer to sell or soliciting an offer to buy our securities in any jurisdiction in which an offer or solicitation is not authorized or in which the person making that offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation. You should assume that the information appearing in this prospectus, the documents incorporated by reference into this prospectus, and in any free writing prospectus that we may authorize for use in connection with this offering, is accurate only as of the date of those respective documents. Our business, financial condition, results of operations and prospects may have changed since those dates.

We are offering to sell, and seeking offers to buy, shares of common stock only in jurisdictions where offers and sales are permitted. The distribution of this prospectus and the offering of the common stock in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus must inform themselves about, and observe any restrictions relating to, the offering of the common stock and the distribution of this prospectus outside the United States. This prospectus does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

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” in this prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus supplement. Accordingly, investors should not place undue reliance on this information.

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PROSPECTUS SUMMARY

This summary highlights selected information contained elsewhere in this prospectus or incorporated by reference in this prospectus, and does not contain all of the information that you need to consider in making your investment decision. You should carefully read the entire prospectus and any related free writing prospectus, including the risks of investing in our securities discussed in the section titled “Risk Factors” contained in this prospectus and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus. You should also carefully read the information incorporated by reference into this prospectus, including our financial statements, and the exhibits to the registration statement of which this prospectus is a part.

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

Vaxart, Inc.

Overview

Corporate Background

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 by us	Shares of our common stock, par value $0.10 per share, with an aggregate sale price of up to $4,250,000.
Common stock to be outstanding after this offering	Up to 8,912,022 shares, assuming sales of 1,770,833 shares of our common stock in this offering at a public offering price of $2.40 per share, which was the last reported sale price of our common stock on the Nasdaq Capital Market on December 18, 2018. The actual number of shares issued will vary depending on the sales price under this offering.
Manner of offering	“At the market offering” that may be made from time to time through or to B. Riley FBR, Inc. , or B. Riley FBR , as sales agent. See the section titled “Plan of Distribution.”
Use of proceeds	We intend to use the net proceeds from this offering, if any, 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	Investment in our securities involves a high degree of risk. You should read the section titled “Risk Factors,” in this prospectus and in the documents incorporated by reference into this prospectus for a discussion of factors to consider before deciding to purchase shares of our common stock.
Nasdaq Capital Market symbol	“VXRT”
The number of shares of common stock outstanding is based on 7,141,189 shares of common stock outstanding as of September 30, 2018, and excludes: • 960,888 shares issuable upon the exercise of outstanding stock options with a weighted average exercise price of $8.82 per share; • 127,652 additional shares reserved for future issuance under our 2016 Equity Incentive Plan; and • 10,914 shares issuable upon the exercise of outstanding warrants with a weighted average exercise price of $22.99 per share.

Unless otherwise stated, information in this prospectus assumes no exercise of outstanding options or warrants.

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RISK FACTORS

You should consider carefully the risks described below and discussed under the section titled “Risk Factors” contained in our Quarterly Report on Form 10-Q for the three months ended September 30, 2018 as updated by our subsequent filings under the Securities Exchange Act of 1934, as amended, or the Exchange Act, each of which is incorporated by reference in this prospectus in their entirety, together with other information in this prospectus, and the information and documents incorporated by reference in this prospectus, and any free writing prospectus that we have authorized for use in connection with this offering before you make a decision to invest in our common stock. If any of the following events actually occur, our business, operating results, prospects or financial condition could be harmed. This could cause the trading price of our common stock to decline and you may lose all or part of your investment. The risks below and incorporated by reference in this prospectus are not the only ones we face. Additional risks not currently known to us or that we currently deem immaterial may also affect our business operations. Please also read carefully the section below titled “Special Note Regarding Forward-Looking Statements.”

Risks Relating to The Offering

Our stock price is and may continue to be volatile and you may not be able to resell our securities at or above the price you paid.

The market price for our common stock is volatile and may fluctuate significantly in response to a number of factors, most of which we cannot control, such as quarterly fluctuations in financial results, announcements of new technologies impacting our products, announcements by competitors or changes in securities analysts’ recommendations could cause the price of our stock to fluctuate substantially. Each of these factors, among others, could harm your investment in our common stock and could result in your being unable to resell the common stock that you purchase at a price equal to or above the price you paid.

Sales of a significant number of shares of our common stock in the public markets, or the perception that such sales could occur, could depress the market price of our common stock.

Sales of a substantial number of shares of our common stock in the public markets could depress the market price of our common stock and impair our ability to raise capital through the sale of additional equity securities. We cannot predict the effect that future sales of our common stock would have on the market price of our common stock.

Our management team may invest or spend the proceeds of this offering in ways with which you may not agree or in ways which may not yield a significant return.

Our management will have broad discretion over the use of proceeds from this offering. The net proceeds from this offering will be used to support the clinical and preclinical development of our product candidates, and 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 . We may also use a portion of the net proceeds to in-license, acquire or invest in complementary businesses or products; however, we have no current commitments or obligations to do so.

Our management will have considerable discretion in the application of the net proceeds, and you will not have the opportunity, as part of your investment decision, to assess whether the proceeds are being used appropriately. The net proceeds may be used for corporate purposes that do not increase our operating results or enhance the value of our common stock.

You may experience immediate and substantial dilution.

The offering price per share in this offering will exceed the net tangible book value per share of our common stock outstanding prior to this offering. Assuming that 1,770,833 shares of our common stock are sold in this offering, based on an assumed sale price of $2.40 per share, the last sale price of a share of our common stock on the Nasdaq Capital Market on December 18, 2018, you will experience immediate dilution, representing the difference between the price you pay and our as adjusted net tangible book value per share as of September 30, 2018, after giving effect to this offering, of $2.46 per share. The exercise of outstanding stock options or warrants may result in further dilution of your investment. See the section titled “Dilution” below for a more detailed illustration of the dilution you would incur if you participate in this offering.

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You may experience future dilution as a result of future equity offerings.

To raise additional capital, we may in the future offer additional shares of our common stock or other securities convertible into or exchangeable for our common stock at prices that may not be the same as the price per share in this offering. We may sell shares or other securities in any other offering at a price per share that is less 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. The price per share at which we sell additional shares of our common stock, or securities convertible or exchangeable into common stock, in future transactions may be higher or lower than the price per share paid by investors in this offering.

S-4

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and the documents we have filed with 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 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: