This report includes "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933, as amended (the "Securities Act"), and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). Those statements include statements regarding the intent, belief or current expectations of Seelos Therapeutics, Inc. and its subsidiaries ("we," "us," "our," the "Company" or "Seelos") and our management team. Any such forward-looking statements are not guarantees of future performance and involve risks and uncertainties, and actual results may differ materially from those projected in the forward-looking statements. These risks and uncertainties include but are not limited to those risks and uncertainties set forth in Item 1A of this Report. In light of the significant risks and uncertainties inherent in the forward-looking statements included in this Report, the inclusion of such statements should not be regarded as a representation by us or any other person that our objectives and plans will be achieved. Further, these forward-looking statements reflect our view only as of the date of this report. Except as required by law, we undertake no obligations to update any forward-looking statements and we disclaim any intent to update forward-looking statements after the date of this report to reflect subsequent developments. Accordingly, you should also carefully consider the factors set forth in other reports or documents that we file from time to time with the Securities and Exchange Commission ("SEC").

We have common law trademark rights in the unregistered marks "Seelos Therapeutics, Inc.," "Seelos" and the Seelos logo in certain jurisdictions. Vitaros is a registered trademark of Ferring International Center S.A. ("Ferring") in certain countries outside of the United States. This Annual Report on Form 10-K also includes trademarks, tradenames and service marks that are the property of other organizations. Solely for convenience, trademarks and tradenames referred to in this Annual Report on Form 10-K appear without the ^® and ^™ symbols, but those references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or that the applicable owner will not assert its rights, to these trademarks and tradenames.

We are a clinical-stage biopharmaceutical company focused on achieving efficient development of products that address significant unmet needs in Central Nervous System ("CNS") disorders and other rare disorders.

Our business model is to advance multiple late-stage therapeutic candidates as well as earlier stage assets with proven mechanisms of action or with strong scientific rationale that address large markets with unmet medical needs and for which there is a strong economic and scientific rationale for development.

Our product development pipeline is as follows:

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Lead Programs

Our lead programs are currently SLS-002 for the treatment of acute suicidal ideation and behavior ("ASIB") in major depressive disorder ("MDD"), and SLS-005 for the potential treatment of Amyotrophic Lateral Sclerosis ("ALS"). SLS-005 for the potential treatment of Sanfilippo Syndromes currently requires additional natural history data, which is being explored.

SLS-002 is intranasal racemic ketamine with two investigational new drug applications ("INDs"), the lead program is focused on the treatment of ASIB in MDD. SLS-002 was originally derived from a Javelin Pharmaceuticals, Inc./Hospira, Inc. program with 16 clinical studies involving approximately 500 subjects. SLS-002 addresses an unmet need for an efficacious drug to treat suicidality in the United States. Traditionally, anti-depressants have been used in this setting but many of the existing treatments are known to contribute to an increased risk of suicidal thoughts in some circumstances, and if and when they are effective, it often takes weeks for the full therapeutic effect to be manifested. We believe there is a large opportunity in the United States and European markets for products in this space. Based on information gathered from the databases of the Agency for Healthcare Research and Quality, there were more than 500,000 visits to emergency rooms for suicide attempts in 2013 in the United States alone. Experimental studies suggest ketamine has the potential to be a rapid, effective treatment for refractory depression and suicidality. The clinical development program for SLS-002 includes two parallel healthy volunteer studies (Phase I). We announced interim data from our Phase I study of SLS-002 during the quarterly period ended March 31, 2020. The study demonstrated that 90mg of SLS-002, when administered as a monotherapy and in combination with an oral antidepressant, was generally safe and well-tolerated. Further, in March 2020, we completed a Type C meeting with the U.S. Food and Drug Administration (the "FDA") and received guidance to conduct a Phase II proof of concept study of SLS-002 for ASIB in patients with MDD, to support the further clinical development of this product candidate, together with nonclinical data under development. As a result of the Type C meeting and the Fast Track designation for SLS-002 for the treatment of ASIB in patients with MDD, we believe we are well positioned to pursue the FDA's expedited programs for drug development and review. On June 23, 2020, we announced the final safety data from our Phase I pharmacokinetics/pharmacodynamics study of intranasal racemic ketamine (SLS-002) as well as the planned design of a Phase II, double blind, placebo-controlled Proof of Concept ("PoC") study for ASIB in patients with MDD. We initiated this PoC study in two parts: Part A is an open-label study of 16 patients, and will be followed by Part B, which is a double blind, placebo-controlled study of approximately 120 patients. On January 15, 2021, we announced dosing of the first patients in Part A of the PoC study.

SLS-005 is IV Trehalose, a protein stabilizer that crosses the blood-brain-barrier, activates autophagy and lysosomal biogenesis. Based on the pre-clinical and in-vitro studies, there is a sound scientific rationale for developing Trehalose for the treatment of ALS and other indications such as Sanfilippo syndromes. Trehalose is a low molecular weight disaccharide (.342 kDa) that protects against pathological processes in cells. It has been shown to penetrate muscle and cross the blood-brain-barrier. In animal models of several diseases associated with abnormal cellular-protein aggregation, it has been shown to reduce pathological aggregation of misfolded proteins as well as to activate autophagy pathways through the activation of Transcription Factor EB ("TFEB"), a key factor in lysosomal and autophagy gene expression. Activation of TFEB is an emerging therapeutic target for a number of diseases with pathologic accumulation of storage material.

Trehalose 90 mg/mL IV solution has demonstrated promising clinical potential in prior Phase II clinical development for oculopharyngeal muscular dystrophy ("OPMD") and spinocerebellar ataxia type 3 ("SCA3"), also known as Machado Joseph disease, with a good safety profile and encouraging efficacy results. Pathological accumulation of protein aggregates within cells, whether in the CNS or in muscle, eventually leads to loss of function and ultimately cell death. Prior preclinical studies indicate that this platform has the potential to prevent mutant protein aggregation in other devastating PolyA/PolyQ diseases.

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We own two United States patents for parenteral administration of trehalose for patients with OPMD and SCA3, both of which are expected to expire in 2034. In addition, Orphan Drug Designation for OPMD and SCA3 has been secured in the United States and in the European Union ("EU"). In February 2019, we assumed a collaborative agreement, turned subsequently into a research grant, with Team Sanfilippo Foundation ("TSF"), a nonprofit medical research foundation founded by parents of children with Sanfilippo syndrome. On April 30, 2020, we were granted Orphan Drug Designation ("ODD") for SLS-005 in Sanfilippo syndrome from the FDA. SLS-005 was previously granted ODD from the FDA and European Medicines Agency for SCA3 and OPMD as well as Fast Track designation for OPMD. On April 22, 2020, we received a Notice of Allowance from the United States Patent and Trademark Office for our U.S. patent number 10,751,353 (application number 16/263,707) titled "COMPOSITIONS AND METHODS FOR TREATING AN AGGREGATION DISEASE OR DISORDER" for trehalose (SLS-005). The allowed claims cover the composition of matter and method of use for trehalose (SLS-005) for treating a disease or disorder selected from any one of the following: Spinal and bulbar muscular atrophy; Dentatombral-pallidoluysian atrophy; Pick's disease; corticobasal degeneration; progressive supranuclear palsy; frontotemporal dementia; or parkinsonism linked to chromosome 17. On May 15, 2020, we were granted Rare Pediatric Disease Designation ("RPDD") for SLS-005 in Sanfilippo syndrome from the FDA. RPDD is an incentive program created under the Federal Food, Drug, and Cosmetic Act to encourage the development of new therapies for the prevention and treatment of certain rare pediatric diseases. At present, we are initiating the startup activities for a clinical study in ALS. In December 2020, we announced the selection of SLS-005 for the Healey ALS platform trial led by the Harvard Medical School, Massachusetts. The Healey ALS platform trial is designed to study multiple potential treatments for ALS simultaneously. The platform trial model aims to greatly accelerate the study access, reduce costs and shorten development timelines.

Additionally, we are developing several preclinical programs, most of which have well-defined mechanisms of action, including: SLS-004, licensed from Duke University, and SLS-007, licensed from The Regents of the University of California, for the potential treatment of Parkinson's Disease ("PD"), SLS-008, targeted at chronic inflammation in asthma and orphan indications such as pediatric esophagitis, SLS-010 in narcolepsy and related disorders and SLS-012, an injectable therapy for post-operative pain management.

SLS-002: The clinical development program for SLS-002 includes two parallel healthy volunteer studies (Phase I). Following these Phase I studies, we completed a Type C meeting with the FDA in March 2020 and received guidance to conduct a Phase II proof of concept study of SLS-002 for ASIB in patients with MDD. The startup activities are underway and have enrolled several patients in Part A of our open-label study.

SLS-005 is undergoing startup activities for a clinical study in ALS. In December 2020, we announced the selection of SLS-005 for the Healey ALS platform trial led by the Harvard Medical School, Massachusetts. The Healey ALS platform trial is designed to study multiple potential treatments for ALS simultaneously. The platform trial model aims to greatly accelerate the study access, reduce costs, and shorten development timelines. We are continuing to explore trials in Sanfilippo syndromes and are seeking more natural history data based on the guidance from regulatory agencies.

SLS-004 is an all-in-one lentiviral vector, targeted for gene editing through DNA methylation within intron 1 of the SNCA gene responsible for expressing alpha-synuclein protein. SLS-004, when delivered to dopaminergic neurons derived from human induced pluripotent stem cells (hiPSCs) of a PD patient, modified the expression on alpha-synuclein and exhibited reversal of the disease-related cellular-phenotypes characteristics of the neurons. The role of mutated SNCA in PD pathogenesis and the need to maintain the normal physiological levels of alpha-synuclein protein emphasize the so-far unmet need to develop new therapeutic strategies, such as SLS-004, targeting the regulatory mechanism of alpha-synuclein expression.

On May 28, 2020, we announced the initiation of a preclinical study of SLS-004 in PD through an all-in-one lentiviral vector targeting the synuclein alpha gene. We are constructing a bimodular viral system harboring an endogenous alpha-synuclein (α-synuclein) transgene and inducible regulated repressive CRISPR/Cas9-unit to achieve constitutive activation and inducible suppression of PD-related pathologies.

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SLS-006 is a true partial dopamine agonist, originally developed by Wyeth Pharmaceuticals, Inc., with previous clinical studies on 340 subjects in various Phase I and Phase II studies. It is a potent D2/D3 agonist/antagonist that has shown promising efficacy with statistical significance in Phase II studies in early stage PD patients and an attractive safety profile. Moreover, it has also shown synergistic effect with reduced doses of L-DOPA. We are evaluating studies to advance the product candidate into late stage trials.

SLS-008 is an orally available antagonist for Chemoattractant Receptor-homologous molecules expressed on TH2 cells ("CRTh2"), targeted at chronic inflammation in asthma and a pediatric orphan indication. We have a "family" of compounds under our SLS-008 program. We intend to file an IND after completion of IND-enabling studies, which are currently in progress, in an undisclosed pediatric orphan indication where there is a high unmet need for an effective oral therapy.

Additionally, we are developing several preclinical programs, most of which have well-defined mechanisms of action, including:

• SLS-010, an oral histamine H3A receptor antagonist that shows promising activity in narcolepsy and related disorders; and
• SLS-012, an injectable therapy for post-operative pain management.

In March 2020, we began taking precautionary measures to protect the health and safety of our employees and contractors and further assessing the actual and potential impact of the coronavirus ("COVID-19") pandemic on our business, financial condition and operations. COVID-19 infections have been reported throughout the United States, along with other jurisdictions in which our suppliers, partners and collaborators operate. In addition, COVID-19 has caused disruption and volatility in the global capital markets, and has led to an economic slowdown. Certain national, provincial, state and local governmental authorities have issued proclamations and/or directives aimed at minimizing the spread of COVID-19 and additional, more restrictive proclamations and/or directives may be issued in the future. Before the recent COVID-19 outbreak, most of our employees worked remotely. In addition, our clinical trial for SLS-002 in ASIB in MDD completed the clinical testing phase in February 2020. On June 23, 2020, we released the final pharmacokinetics/pharmacodynamics portion of the data. Also, we did not experience any significant delays with opening our clinical sites for SLS-002 during the fourth quarter of 2020 and have not experienced any such delays during the first quarter of 2021 to date. Accordingly, the impact of the travel restrictions and shelter-in-place orders have not had a material impact on our operations to date. Additionally, the pandemic has not materially affected our liquidity as we maintain our resources in the form of cash.

In addition, although we do not currently expect the preventative measures taken to date to have a material adverse impact on our business for the first half of 2021, the ultimate impact of the COVID-19 pandemic on our business, financial condition and results of operations is unknown and will depend on future developments and risks, which are highly uncertain and cannot be predicted. These developments and risks include, among others, the duration and severity of the COVID-19 pandemic, the impact on capital markets, the impact on our partners and the regulatory agencies that oversee our sector and any additional

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preventative and protective actions that governmental authorities, or we, may implement, any of which may result in an extended period of business disruption, including potential delays in commencing future clinical trials, or in completing enrollment for any clinical trials we may commence or in the FDA or other regulatory agencies conducting in-person inspections or accommodations for alternatives to in-person inspections. Any resulting financial impact cannot be reasonably estimated at this time, but the COVID-19 pandemic may force us to make adjustments to our business, our plans and our timeline for developing assets, including our programs. In addition, the pandemic is currently not anticipated to have a material adverse impact on our business, financial condition and results of operations, including our ability to raise additional capital, although, if the pandemic continues at its current rate into the first quarter of 2021, it could have a material adverse impact on our business.

On January 24, 2019, Apricus Biosciences, Inc., a Nevada corporation ("Apricus"), completed a business combination with Seelos Therapeutics, Inc., a Delaware corporation ("STI"), in accordance with the terms of the Agreement and Plan of Merger and Reorganization (the "Merger Agreement") entered into on July 30, 2018. Pursuant to the Merger Agreement, (i) a subsidiary of Apricus merged with and into STI, with STI (renamed as "Seelos Corporation") continuing as a wholly-owned subsidiary of Apricus and the surviving corporation of the merger and (ii) Apricus was renamed as "Seelos Therapeutics, Inc." (the "Merger"). Upon completion of the Merger, our business became primarily the business conducted by STI, which was a clinical-stage biopharmaceutical company focused on the development and commercialization of CNS therapeutics with known mechanisms of action in areas with a highly unmet medical need. Also, on January 23, 2019, in connection with, and prior to the completion of, the Merger, we effected a reverse stock split of our common stock at a ratio of 1-for-30 (the "Reverse Stock Split"). Our previous ticker symbol was "APRI". Shares of our common stock commenced trading on the Nasdaq Capital Market under the ticker symbol "SEEL" as of market open on January 24, 2019. See Note 1 to our consolidated financial statements for more information regarding the Merger.

On February 15, 2019, we entered into an Asset Purchase Agreement (the "Bioblast Asset Purchase Agreement") with Bioblast. Pursuant to the Bioblast Asset Purchase Agreement, we acquired all of the assets of Bioblast relating to a therapeutic platform known as Trehalose (the "Bioblast Asset Purchase"). At the closing of the Bioblast Asset Purchase (the "Bioblast Closing"), we paid to Bioblast $1.5 million in cash in February 2019 and an additional $2.0 million in cash in February 2020. Accordingly, we recognized a $3.5 million charge to research and development expense during the three months ended March 31, 2019. Under the terms of the Bioblast Asset Purchase Agreement, we agreed to pay additional consideration to Bioblast upon the achievement of certain milestones in the future, as follows: (1) within 15 days following the completion of our or our affiliate's first Phase II(b) clinical trial of Trehalose satisfying certain criteria, we will pay to Bioblast $8.5 million in cash; and (2) within 15 days following the approval for commercialization by the FDA or the Health Products and Food Branch of Health Canada of the first new drug application (an "NDA") or New Drug Submission, respectively, of Trehalose filed by us or our affiliates, we will pay to Bioblast $8.5 million in cash. In addition, we agreed to pay Bioblast a cash royalty equal to 1% of the net sales of Trehalose. Under the terms of the Bioblast Asset Purchase, we assumed a collaborative agreement with TSF, a nonprofit medical research foundation founded by parents of children with Sanfilippo syndrome. TSF, upon approval by the FDA, plans to begin a Phase II(b)/III clinical trial in up to 24 patients with Sanfilippo syndrome, which is now known under the study name SLS-005. We will provide the clinical supply of Trehalose. The terms of the Bioblast Asset Purchase Agreement entitle us to access all clinical data from this trial. On July 15, 2019, we amended the agreement whereby we agreed to assume responsibility for the Phase II(b)/III clinical trial and TSF agreed to provide a grant of up to $1.5 million towards the funding of the trial.

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Acquisition of Assets from Vyera Pharmaceuticals, AG ("Vyera")

As consideration for the Vyera Assets, we paid to Vyera a non-refundable cash payment of $150,000 on May 21, 2018. As further consideration for the Vyera Assets, upon public announcement of the entry by Apricus and STI into the Merger Agreement, we paid to Vyera a non-refundable cash payment of $150,000. As further consideration for the Vyera Assets, we issued to Vyera 191,529 shares of common stock and paid Vyera a non-refundable cash payment $1,000,000 on January 29, 2019.

Pursuant to the amendment to the asset purchase agreement entered into with Vyera on October 15, 2019, we issued Vyera 1,809,845 registered shares of our common stock on January 2, 2020 and made cash payments to Vyera in the amounts of $750,000, $750,000, $1.0 million and $1.0 million in October 2019, January 2020, April 2020 and July 2020, respectively.

Pursuant to the amendment to the asset purchase agreement entered into with Vyera on February 15, 2021, we agreed to make cash payments to Vyera in the amount of $3.0 million in each of February 2021, June 2021 and September 2021 in exchange for a lower royalty percentage on potential net sales of SLS-002.

In the event that we sell, directly or indirectly, all or substantially all of the Vyera Assets to a third party, then we must pay Vyera an amount equal to 4% of the net proceeds actually received by us as an upfront payment in such sale.

We agreed to pay to Vyera certain one-time, non-refundable milestone payments consisting of (i) $10.0 million upon approval by the FDA of an NDA, with respect to SLS-002, (ii) $5.0 million upon approval by the European Medicines Agency (the "EMA") of the foreign equivalent to an NDA with respect to SLS-002 in the EU (either in its entirety or including at least one of France, Germany or, if at the time the United Kingdom is a member of the EU, the United Kingdom), the United Kingdom, if at the time the United Kingdom is not a member of the EU, Japan or the People's Republic of China (each, a "Major Market"), (iii) $2.5 million upon approval by the EMA of the foreign equivalent to an NDA with respect to SLS-002 in a second Major Market, (iv) $5.0 million upon the achievement of $250.0 million in net sales of SLS-002, (v) $10.0 million upon the achievement of $500.0 million in net sales of SLS-002, (vi) $15.0 million upon the achievement of $1.0 billion in net sales of SLS-002, (vii) $20.0 million upon the achievement of $1.5 billion in net sales of SLS-002, and (viii) $25.0 million upon the achievement of $2.0 billion in net sales of SLS-002. We will also pay to Vyera a royalty percentage in the mid-single digits on aggregate annual net sales of SLS-002.

On August 29, 2019, we entered into an amended and restated exclusive license agreement with Stuart Weg, M.D. (the "Weg License Agreement"), pursuant to which we were granted an exclusive worldwide license to certain intellectual property and regulatory materials related to SLS-002. Under the terms of the Weg License Agreement, we paid an upfront license fee of $75,000 upon execution of the agreement. We agreed to pay additional consideration to Dr. Weg as follows: (i) $0.1 million on January 2, 2020, (ii) $0.125 million on January 2, 2021, and (iii) in the event the FDA has not approved an NDA for a product containing ketamine in any dosage on or before December 31, 2021, $0.2 million on January 2, 2022. We paid the required $0.1 million on January 2, 2020 and $0.125 million on January 2, 2021. As further consideration, we agreed to pay Dr. Weg certain milestone payments consisting of (i) $0.1 million and shares of common stock equal to $0.15 million divided by the closing sales price of our common stock upon the issuance of the first patent directed to an anxiety indication, (ii) $0.5 million after the locking of the database and unblinding the data for the statistically significant readout of a Phase III trial of an intranasal racemic ketamine product that has been conducted for the submission under an NDA or equivalent seeking regulatory approval in the United States, the United Kingdom, France, Germany, Italy, Spain, China or Japan, or seeking regulatory from the EMA in the EU, for such product (the "Milestone Product"), (iii) $3.0 million upon FDA approval of an NDA for the

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Milestone Product, (iv) $2.0 million upon regulatory approval by the EMA for the Milestone Product, and (v) $1.5 million upon regulatory approval in Japan for the Milestone Product; provided, however, that the maximum amount to be paid by us under milestones (i)-(v) will be $6.6 million. We will also pay to Dr. Weg a royalty percentage equal to 2.25% on the sale of each product containing ketamine in any dosage.

On June 27, 2019, we entered into an exclusive license agreement (the "Duke License Agreement") with Duke University pursuant to which we were granted an exclusive license to a gene therapy program targeting the regulation of the SNCA gene, which encodes alpha-synuclein expression. We plan to study this initial approach in PD and will further evaluate the potential clinical approach in other disorders affecting the CNS. This program is now known as SLS-004. Upon entry into the Duke License Agreement, we paid to Duke University $0.1 million. We agreed to pay additional consideration to Duke University upon the achievement of certain milestones in the future, as follows: (i) within 30 days following filing of an IND following the completion of preclinical studies including comprehensive validation of the platform, we will pay $0.1 million; (ii) within 30 days following dosing of the first patient in a Phase I clinical trial, we will pay $0.2 million; (iii) within 30 days following dosing of the first patient in a Phase II clinical trial, we will pay $0.5 million; (iv) within 30 days following dosing of the first patient in a Phase III clinical trial, we will pay $1.0 million; and (v) within 30 days following an NDA approval, we will pay $2.0 million. We are also obligated to pay a single digit royalty on sales of the product, if any. In addition, if we fail to achieve certain milestones within a specified timeframe, Duke University may terminate the agreement.

On September 21, 2016, we entered into a License Agreement (the "License Agreement") with Ligand Pharmaceuticals Incorporated ("Ligand"), Neurogen Corporation and CyDex Pharmaceuticals, Inc. (collectively, the "Licensors"), pursuant to which, among other things, the Licensors granted to us an exclusive, perpetual, irrevocable, worldwide, royalty-bearing, nontransferable right and license under (i) patents related to a product known as Aplindore, which is now known as SLS-006, acetaminophen (as it may have been or may be modified for use in a product to be administered by any method in any form including, without limitation injection and intravenously, the sole active pharmaceutical ingredient of which is acetaminophen), which is now known as SLS-012, an H3 receptor antagonist, which is now known as SLS-010, and either or both of the Licensors' two proprietary CRTh2 antagonists, which are now known collectively as SLS-008 (collectively, the "Licensed Products"), and (ii) copyrights, trade secrets, moral rights and all other intellectual and proprietary rights related thereto. We are obligated to use commercially reasonable efforts to (a) develop the Licensed Products, (b) obtain regulatory approval for the

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Licensed Products in the United States or a Major Market, and (c) commercialize the Licensed Products in each country where regulatory approval is obtained. We have the exclusive right and sole responsibility and decision-making authority to research and develop any Licensed Products and to conduct all clinical trials and non-clinical studies we believe appropriate to obtain regulatory approvals for commercialization of the Licensed Products. We also have the exclusive right and sole responsibility and decision-making authority to commercialize any of the Licensed Products.

As partial consideration for the grant of the rights and licenses under the License Agreement, we paid to Ligand a nominal option fee. As further partial consideration for the grant of the rights and licenses to us under the License Agreement, we are obligated to pay to Ligand an aggregate of $1.3 million within 30 days after the closing of the issuance and sale by us of debt and/or equity securities for gross proceeds to us of at least $7.5 million. In connection with the closing of the Merger, we issued 392,307 shares of common stock to settle this obligation. As further partial consideration for the grant of the rights and licenses to us by Ligand under the License Agreement, we agreed to pay to Ligand certain one-time, non-refundable milestone payments upon the achievement of certain financing milestones, consisting of (i) the lesser of $3.5 million or 10% of the net proceeds to us in the event of our initial public offering or a financing transaction consummated in connection with a transaction as a result of which our business becomes owned or controlled by an existing issuer with a class of securities registered under the Exchange Act and immediately after such transaction, the security holders of us as of immediately before such transaction own, as a result of such transaction, at least 35% of the equity securities or voting power of such issuer, or (ii) the lesser of $3.5 million or 10% of the net proceeds to us in the event we are acquired. In connection with the closing of the Merger, we issued 408,946 shares of common stock to settle this obligation.

As further partial consideration for the grant of the rights and licenses under the License Agreement, we agreed to pay to Ligand certain one-time, non-refundable regulatory milestone payments in connection with the Licensed Products, other than in connection with Aplindore for the indication of PD or Restless Leg Syndrome, consisting of (i) $750,000 upon submission of an application with the FDA or equivalent foreign body for a particular Licensed Product, (ii) $3.0 million upon FDA approval of an application for a particular Licensed Product, (iii) $1.125 million upon regulatory approval in a Major Market for a particular Licensed Product, and (iv) $1.125 million upon regulatory approval in a second Major Market for a particular Licensed Product.

As further partial consideration for the grant of the rights and licenses under the License Agreement, we agreed to pay to Ligand certain one-time, non-refundable regulatory milestone payments in connection with the Licensed Products in connection with Aplindore for the indication of PD or Restless Leg Syndrome, consisting of (i) $100,000 upon submission of an application with the FDA or equivalent foreign body for such a particular Licensed Product, (ii) $350,000 upon FDA approval of an application for such a particular Licensed Product, (iii) $125,000 upon regulatory approval in a Major Market for such a particular Licensed Product, and (iv) $125,000 upon regulatory approval in a second Major Market for such a particular Licensed Product.

As further partial consideration for the grant of the rights and licenses under the License Agreement, we agreed to pay to Ligand certain one-time, non-refundable commercial milestone payments in connection with the Licensed Products, consisting of (i) $10.0 million upon the achievement of $1.0 billion of cumulative worldwide net sales of Licensed Products based upon Aplindore, (ii) $10.0 million upon the achievement of $1.0 billion of cumulative worldwide net sales of Licensed Products based upon an H3 receptor antagonist, (iii) $10.0 million upon the achievement of $1.0 billion of cumulative worldwide net sales of Licensed Products based upon acetaminophen (as it may have been or may be modified for use in a product to be administered by any method in any form including, without limitation injection and intravenously, the sole active pharmaceutical ingredient of which is acetaminophen), (iv) $10.0 million upon the achievement of $1.0 billion of cumulative worldwide net sales of Licensed Products based upon CRTh2 antagonists, (v) $20.0 million upon the achievement of $2.0 billion of cumulative worldwide net sales of Licensed Products based upon Aplindore, (vi) $20.0 million upon the achievement of $2.0 billion of cumulative worldwide net sales of Licensed Products based upon an H3 receptor antagonist, (vii) $20.0 million upon the achievement of $2.0 billion of cumulative worldwide net sales of Licensed Products based upon acetaminophen (as it may have been or may be modified for use in a product to be administered by any method in any form including, without limitation injection and intravenously, the sole active pharmaceutical ingredient of which is acetaminophen),

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and (viii) $20.0 million upon the achievement of $2.0 billion of cumulative worldwide net sales of Licensed Products based upon CRTh2 antagonists.

We will also pay to Ligand middle single-digit royalties on aggregate annual net sales of Licensed Products other than in connection with Aplindore for the indication of PD or Restless Leg Syndrome in a country where such Licensed Products are covered under a licensed patent and a tiered incremental royalty in the upper single digit to lower double digit range on aggregate annual net sales of Licensed Products in connection with Aplindore for the indication of PD or Restless Leg Syndrome in a country where such Licensed Products are covered under a licensed patent. Additionally, we will pay to Ligand low single digit royalties on aggregate annual net sales of Licensed Products other than in connection with Aplindore for the indication of PD or Restless Leg Syndrome in a country where such Licensed Products are not covered under a licensed patent and a tiered incremental royalty in the lower single digit to middle single digit range on aggregate annual net sales of Licensed Products in connection with Aplindore for the indication of PD or Restless Leg Syndrome in a country where such Licensed Products are not covered under a licensed patent.

As a result of the Merger, our going-forward operations are primarily those of STI. Pursuant to the Merger, we retained certain assets and technologies that were Apricus' assets and technologies before the consummation of the Merger. Despite our expectation that our primary operations will be those of STI on a going-forward basis, we may choose to monetize legacy Apricus assets in the future. We may also seek to monetize such assets pursuant to certain contractual obligations. Prior to the closing of the Merger, in addition to strategic efforts, we had been historically focused on the development of innovative product candidates in the areas of urology and rheumatology. We have two legacy product candidates: a product candidate in the United States intended for the topical treatment of erectile dysfunction ("ED"), which we in-licensed from Warner Chilcott Company, Inc., now a subsidiary of Allergan plc ("Allergan") (the "CVR Product Candidate"); and a product candidate which has completed a Phase IIa clinical trial for the treatment of Raynaud's Phenomenon, secondary to scleroderma, for which we own worldwide rights. At the closing of the Merger, we entered into a Contingent Value Rights Agreement (the "CVR Agreement") with STI, Richard Pascoe, as representative of holders of the contingent value rights ("CVRs"), and a rights agent. Pursuant to the CVR Agreement, each of the Apricus pre-Merger stockholders received one CVR for each share of Apricus common stock held of record immediately prior to the closing of the Merger. Each CVR represents the right to receive payments based on the CVR Product Candidate and certain related assets and technologies. In particular, the holders of the CVRs will be entitled to receive 90% of any cash payments (or the fair market value of any non-cash payments) exceeding $500,000 received, during a period of ten years from the closing of the Merger, based on the sale or out-licensing of the CVR Product Candidate or related assets and technologies, including any milestone payments, less reasonable transaction expenses.

As of March 4, 2021, we owned or in-licensed approximately 38 issued patents that relate to our core programs, which will expire from 2021 through 2034, approximately. Also, as of that same date, we owned or in-licensed approximately 47 patent applications that relate to our core programs, which if ultimately issued would expire as late as approximately 2041, based upon the potential expiration date of the last to expire of those patent applications.

To further strengthen our global patent position on our proprietary products under development and to expand the patent protection to other markets, we have filed foreign patent applications, many of which correspond to our issued United States patents and pending United States patent applications. These foreign filings have resulted in numerous issued patents and currently pending patent applications.

While we have obtained patents and have patent applications pending, the extent of effective patent protection in the United States and other countries is highly uncertain. No consistent policy addresses the breadth of claims allowed in or the degree of protection afforded under patents of medical and pharmaceutical companies. Patents we currently own or may obtain might not be sufficiently broad to protect us against competitors with similar technology. Any of our patents could be invalidated or circumvented.

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The holders of competing patents could determine to commence a lawsuit against us and may even prevail in any such lawsuit. Litigation could result in substantial cost to and diversion of effort by us, which may harm our business. In addition, our efforts to protect or defend our proprietary rights may not be successful or, even if successful, may result in substantial cost to us.

As of March 4, 2021, we owned approximately 5 registered trademarks and 2 pending trademark applications worldwide. We have common law trademark rights in the unregistered marks "Seelos Therapeutics, Inc.," "Seelos" and the Seelos logo in certain jurisdictions. Vitaros is a registered trademark of Ferring in certain countries outside of the United States.

While we have obtained registered trademarks, have trademark applications pending and may have common law trademark rights where applicable, the extent of effective trademark protection in the United States and other countries is highly uncertain. Trademarks we currently own or may obtain might not be sufficiently broad to protect us against competitors. Any of our trademarks could be invalidated or circumvented.

Even where we have registered trademarks, competitors could seek to invalidate these registrations. Any such litigation could result in substantial cost to and diversion of effort by us, which may harm our business. In addition, our efforts to protect or defend our proprietary rights may not be successful or, even if successful, may result in substantial cost to us.

Government authorities in the United States (including federal, state and local authorities) and in other countries, extensively regulate, among other things, the manufacturing, research and clinical development, marketing, labeling and packaging, storage, distribution, post-approval monitoring and reporting, advertising and promotion, pricing and export and import of pharmaceutical products, such as our products and product candidates. The process of obtaining regulatory approvals and the subsequent compliance with appropriate federal, state, local and foreign statutes and regulations require the expenditure of substantial time and financial resources. Moreover, failure to comply with applicable regulatory requirements may result in, among other things, warning letters, clinical holds, civil or criminal penalties, recall or seizure of products, injunction, disbarment, partial or total suspension of production or withdrawal of the product from the market. Any agency or judicial enforcement action could have a material adverse effect on us.

In the United States, the FDA regulates drugs and medical devices under the Federal Food, Drug, and Cosmetic Act ("FDCA"), and its implementing regulations. Drugs and devices are also subject to other federal, state and local statutes and regulations. Our product candidates are subject to regulation as combination products, which means that they are composed of both a drug product and device product. If marketed individually, each component would be subject to different regulatory pathways and reviewed by different Centers within the FDA. A combination product, however, is assigned to a Center that will have primary jurisdiction over its regulation based on a determination of the combination product's primary mode of action, which is the single mode of action that provides the most important therapeutic action. In the case of our product candidates, we believe the primary mode of action is attributable to the drug component of the product, which means that the FDA's Center for Drug Evaluation and Research would have primary jurisdiction over the premarket development, review and approval of our product candidates. Accordingly, we have and plan to continue to investigate our products through the IND framework and seek approval through the NDA pathway. Based on our discussions with the FDA to date, we do not anticipate that the FDA will require a separate medical device authorization for the unit-dose dispenser to be marketed together with our product candidates, though the device component will need to comply with certain requirements applicable to devices. The process required by the FDA before our product candidates may be marketed in the United States generally involves the following:

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• submission to the FDA of an IND which must become effective before human clinical trials may begin and must be updated annually;
• completion of extensive preclinical laboratory tests and preclinical animal studies, all performed in accordance with the FDA's Good Laboratory Practice regulations;
• performance of adequate and well-controlled human clinical trials to establish the safety and efficacy of the product candidate for each proposed indication in accordance with good clinical practices ("GCPs");
• submission to the FDA of an NDA after completion of all pivotal clinical trials;
• a determination by the FDA within 60 days of its receipt of an NDA to file the NDA for review;
• satisfactory completion of an FDA pre-approval inspection of the manufacturing facilities at which the active pharmaceutical ingredient ("API"), and finished drug product are produced and tested to assess compliance with good manufacturing Practices ("cGMP") regulations; and
• FDA review and approval of an NDA prior to any commercial marketing or sale of the drug in the United States.

An IND is a request for authorization from the FDA to administer an investigational drug product to humans. The central focus of an IND submission is on the general investigational plan and the protocol(s) for human studies. The IND also includes results of animal studies or other human studies, as appropriate, as well as manufacturing information, analytical data and any available clinical data or literature to support the use of the investigational new drug. An IND must become effective before human clinical trials may begin. An IND will automatically become effective 30 days after receipt by the FDA, unless before that time the FDA raises concerns or questions related to the proposed clinical trials. In such a case, the IND may be placed on clinical hold and the IND sponsor and the FDA must resolve any outstanding concerns or questions before clinical trials can begin. Accordingly, submission of an IND may or may not result in the FDA allowing clinical trials to commence.

Clinical trials involve the administration of the investigational drug to human subjects under the supervision of qualified investigators in accordance with GCPs, which include the requirement that all research subjects provide their informed consent for their participation in any clinical trial. Clinical trials are conducted under protocols detailing, among other things, the objectives of the study, the parameters to be used in monitoring safety, and the efficacy criteria to be evaluated. A protocol for each clinical trial and any subsequent protocol amendments must be submitted to the FDA as part of the IND. Additionally, approval must also be obtained from each clinical trial site's institutional review board ("IRB") before the trials may be initiated, and the IRB must monitor the study until completed. There are also requirements governing the reporting of ongoing clinical trials and clinical trial results to public registries.

The clinical investigation of a drug is generally divided into three phases. Although the phases are usually conducted sequentially, they may overlap or be combined. The three phases of an investigation are as follows:

• Phase I. Phase I includes the initial introduction of an investigational new drug into humans. Phase I clinical trials are typically closely monitored and may be conducted in patients with the target disease or condition or in healthy volunteers. These studies are designed to evaluate the safety, dosage tolerance, metabolism and pharmacologic actions of the investigational drug in humans, the side effects associated with increasing doses, and if possible, to gain early evidence on effectiveness. During Phase I clinical trials, sufficient information about the investigational drug's pharmacokinetics and pharmacological effects may be obtained to permit the design of well-controlled and scientifically valid Phase II clinical trials. The total number of participants included in Phase I clinical trials varies, but is generally in the range of 20 to 80.
• Phase II. Phase II includes controlled clinical trials conducted to preliminarily or further evaluate the effectiveness of the investigational drug for a particular indication(s) in patients with the disease or condition under study, to determine dosage tolerance and optimal dosage, and to identify possible adverse side effects and safety risks associated with the drug. Phase II clinical trials are typically well-controlled, closely monitored, and conducted in a limited patient population, usually involving no more than several hundred participants.
• Phase III. Phase III clinical trials are generally controlled clinical trials conducted in an expanded patient population generally at geographically dispersed clinical trial sites. They are performed after preliminary evidence suggesting effectiveness of the drug has been obtained, and are intended to further evaluate dosage, clinical effectiveness and safety, to establish the overall benefit-risk relationship of the investigational drug product, and to provide an adequate basis for product approval. Phase III clinical trials usually involve several hundred to several thousand participants.

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A pivotal study is a clinical study which adequately meets regulatory agency requirements for the evaluation of a drug candidate's efficacy and safety such that it can be used to justify the approval of the product. Generally, pivotal studies are also Phase III studies but may be Phase II studies if the trial design provides a well-controlled and reliable assessment of clinical benefit, particularly in situations where there is an unmet medical need.

The FDA, the IRB or the clinical trial sponsor may suspend or terminate a clinical trial at any time on various grounds, including a finding that the research subjects are being exposed to an unacceptable health risk. Additionally, some clinical trials are overseen by an independent group of qualified experts organized by the clinical trial sponsor, known as a data safety monitoring board or committee. This group provides authorization for whether or not a trial may move forward at designated check points based on access to certain data from the study. We may also suspend or terminate a clinical trial based on evolving business objectives and/or competitive climate.

Assuming successful completion of all required testing in accordance with all applicable regulatory requirements, detailed investigational drug product information is submitted to the FDA in the form of an NDA requesting approval to market the product for one or more indications. The application includes all relevant data available from pertinent preclinical and clinical trials, including negative or ambiguous results as well as positive findings, together with detailed information relating to the product's chemistry, manufacturing, controls and proposed labeling, among other things. Data can come from company-sponsored clinical trials intended to test the safety and effectiveness of a use of a product, or from a number of alternative sources, including studies initiated by investigators. To support marketing approval, the data submitted must be sufficient in quality and quantity to establish the safety and effectiveness of the investigational drug product to the satisfaction of the FDA.

Once the NDA submission has been accepted for filing, within 60 days following submission, the FDA's goal is to review applications for new molecular entities within ten months of the filing date or, if the application relates to a serious or life-threatening indication and demonstrates the potential to provide a significant improvement in safety or effectiveness over currently marketed therapies, six months from the filing date. The review process is often significantly extended by FDA requests for additional information or clarification. The FDA may refer the application to an advisory committee for review, evaluation and recommendation as to whether the application should be approved. The FDA is not bound by the recommendation of an advisory committee, but it typically follows such recommendations.

After the FDA evaluates the NDA and conducts inspections of manufacturing facilities where the drug product and/or its active pharmaceutical ingredient will be produced, it may issue an approval letter or a complete response letter. An approval letter authorizes commercial marketing of the drug with specific prescribing information for specific indications. A complete response letter indicates that the review cycle of the application is complete and the application is not ready for approval. A complete response letter may require additional clinical data and/or an additional pivotal Phase III clinical trial(s), and/or other significant, expensive and time-consuming requirements related to clinical trials, preclinical studies or manufacturing. Even if such additional information is submitted, the FDA may ultimately decide that the NDA does not satisfy the criteria for approval. The FDA could also approve the NDA with a risk evaluation and mitigation strategy to mitigate risks, which could include medication guides, physician communication plans, or elements to assure safe use, such as restricted distribution methods, patient registries and other risk minimization tools. The FDA also may condition approval on, among other things, changes to proposed labeling, development of adequate controls and specifications, or a commitment to conduct one or more post-market studies or clinical trials. Such post-market testing may include Phase IV clinical trials and surveillance to further assess and monitor the product's safety and effectiveness after commercialization. Regulatory approval of oncology products often requires that patients in clinical trials be followed for long periods to determine the overall survival benefit of the drug.

After regulatory approval of a drug product is obtained, manufacturers are required to comply with a number of post-approval requirements. The holder of an approved NDA must report, among other things, certain adverse reactions and production problems to the FDA, to provide updated safety and efficacy information, and to comply with requirements concerning advertising and promotional labeling for the approved product. Also, quality control and manufacturing procedures must

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continue to conform to cGMP after approval to ensure and preserve the long-term stability of the drug product and compliance with relevant manufacturing requirements applicable to the device component. The FDA periodically inspects manufacturing facilities to assess compliance with cGMP, which imposes extensive procedural, substantive and record keeping requirements. In addition, changes to the manufacturing process are strictly regulated, and, depending on the significance of the change, may require prior FDA approval before being implemented. FDA regulations also require investigation and correction of any deviations from cGMP and impose reporting and documentation requirements upon us and any third-party manufacturers that we may decide to use. Accordingly, manufacturers must continue to expend time, money and effort in the area of production and quality control to maintain compliance with cGMP and other aspects of regulatory compliance.

We rely, and expect to continue to rely, on third parties for the production of clinical and commercial quantities of our product candidates. Future FDA and state inspections may identify compliance issues at our facilities or at the facilities of our contract manufacturers that may disrupt production or distribution, or require substantial resources to correct. In addition, discovery of previously unknown problems with a product or the failure to comply with applicable requirements may result in restrictions on a product, manufacturer or holder of an approved NDA, including withdrawal or recall of the product from the market or other voluntary, FDA-initiated or judicial action that could delay or prohibit further marketing. Newly discovered or developed safety or effectiveness data may require changes to a product's approved labeling, including the addition of new warnings and contraindications, and also may require the implementation of other risk management measures. Also, new government requirements, including those resulting from new legislation, may be established, or the FDA's policies may change, which could delay or prevent regulatory approval of our products under development.

The Hatch-Waxman Act, established abbreviated FDA approval procedures for drugs that are shown to be equivalent to proprietary drugs previously approved by the FDA through its NDA process. Approval to market and distribute these drugs is obtained by filing an abbreviated new drug application ("ANDA") with the FDA. An ANDA is a comprehensive submission that contains, among other things, data and information pertaining to the active pharmaceutical ingredient, drug product formulation, specifications and stability of the generic drug, as well as analytical methods, manufacturing process validation data and quality control procedures. Premarket applications for generic drugs are termed abbreviated because they generally do not include preclinical and clinical data to demonstrate safety and effectiveness. Instead, a generic applicant must demonstrate that its product is bioequivalent to the innovator drug.

In certain situations, an applicant may obtain ANDA approval of a generic product with a strength or dosage form that differs from a referenced innovator drug pursuant to the filing and approval of an ANDA Suitability Petition. The FDA will approve the generic product as suitable for an ANDA application if it finds that the generic product does not raise new questions of safety and effectiveness as compared to the innovator product. A product is not eligible for ANDA approval if the FDA determines that it is not equivalent to the referenced innovator drug, if it is intended for a different use, or if it is not subject to an approved Suitability Petition. However, such a product might be approved under an NDA, with supportive data from clinical trials.

As an alternative path to FDA approval for modifications to formulations or uses of products previously approved by the FDA, an applicant may submit an NDA under Section 505(b)(2) of the FDCA. Section 505(b)(2) was enacted as part of the Hatch-Waxman Amendments and permits the filing of an NDA where at least some of the information required for approval comes from studies not conducted by, or for, the applicant or for which the applicant has not obtained a right of reference. If the 505(b)(2) applicant can establish that reliance on FDA's previous findings of safety and effectiveness is scientifically appropriate, it may eliminate the need to conduct certain preclinical or clinical studies of the new product. The FDA may also require companies to perform additional studies or measurements, including clinical trials, to support the change from the approved branded reference drug. The FDA may then approve the new product candidate for all, or some, of the label

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indications for which the branded reference drug has been approved, as well as for any new indication sought by the 505(b)(2) applicant. We anticipate filing 505(b)(2) NDAs for our lead product candidates, which would rely, in part, on the FDA's previous findings of safety and efficacy of the active ingredient.

In seeking approval for a drug through an NDA, including a 505(b)(2) NDA, applicants are required to list with the FDA certain patents whose claims cover the applicant's product. Upon approval of an NDA, each of the patents listed in the application for the drug is then published in the Orange Book. Any applicant who files an ANDA seeking approval of a generic equivalent version of a drug listed in the Orange Book or a 505(b)(2) NDA referencing a drug listed in the Orange Book must certify to the FDA that (1) no patent information on the drug product that is the subject of the application has been submitted to the FDA; (2) such patent has expired; (3) the date on which such patent expires; or (4) such patent is invalid or will not be infringed upon by the manufacture, use or sale of the drug product for which the application is submitted. This last certification is known as a paragraph IV certification. A notice of the paragraph IV certification must be provided to each owner of the patent that is the subject of the certification and to the holder of the approved NDA to which the ANDA or 505(b)(2) application refers. The applicant may also elect to submit a ``section viii'' statement certifying that its proposed label does not contain (or carves out) any language regarding the patented method-of-use rather than certify to a listed method-of-use patent. If the reference NDA holder and patent owners assert a patent challenge directed to one of the Orange Book listed patents within 45 days of the receipt of the paragraph IV certification notice, the FDA is prohibited from approving the application until the earlier of 30 months from the receipt of the paragraph IV certification expiration of the patent, settlement of the lawsuit or a decision in the infringement case that is favorable to the applicant. The ANDA or 505(b)(2) application also will not be approved until any applicable non-patent exclusivity listed in the Orange Book for the branded reference drug has expired as described in further detail below.

In addition to patent exclusivity, the holder of the NDA for the listed drug may be entitled to a period of non-patent exclusivity, during which the FDA cannot approve an ANDA or 505(b)(2) application that relies on the listed drug. For example, a pharmaceutical manufacturer may obtain five years of non-patent exclusivity upon NDA approval of a new chemical entity ("NCE"), which is a drug that contains an active moiety that has not been approved by FDA in any other NDA. An ``active moiety'' is defined as the molecule or ion responsible for the drug substance's physiological or pharmacologic action. During the five-year exclusivity period, the FDA cannot accept for filing any ANDA seeking approval of a generic version of that drug or any 505(b)(2) NDA for the same active moiety and that relies on the FDA's findings regarding that drug, except that FDA may accept an application for filing after four years if the follow-on applicant makes a paragraph IV certification. A drug, including one approved under Section 505(b)(2), may obtain a three-year period of exclusivity for a particular condition of approval, or change to a marketed product, such as a new formulation for a previously approved product, if one or more new clinical studies (other than bioavailability or bioequivalence studies) was essential to the approval of the application and was conducted/sponsored by the applicant. Should this occur, the FDA would be precluded from approving any ANDA or 505(b)(2) application for the protected modification until after that three-year exclusivity period has run. However, unlike NCE exclusivity, the FDA can accept an application and begin the review process during the exclusivity period.

In addition to regulations in the United States, we may be subject to a variety of regulations in other jurisdictions governing, among other things, clinical trials and any commercial sales and distribution of our product candidates.

Whether or not we obtain FDA approval for a product, we must obtain the requisite approvals from regulatory authorities in foreign countries prior to the commencement of clinical trials or marketing of the product in those countries. Certain countries outside of the United States have a similar process that requires the submission of a clinical trial application much like the IND prior to the commencement of human clinical trials. In Europe, for example, a clinical trial application ("CTA") must be

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submitted to each country's national health authority and an independent ethics committee, much like the FDA and IRB, respectively. Once the CTA is approved in accordance with a country's requirements, clinical trial development may proceed. The requirements and process governing the conduct of clinical trials, product licensing, pricing and reimbursement vary from country to country. In all cases, the clinical trials are conducted in accordance with cGCPs and the applicable regulatory requirements and the ethical principles that have their origin in the Declaration of Helsinki.

To obtain regulatory approval of an investigational drug under EU regulatory systems, we must submit a marketing authorization application. The application used to file the NDA in the United States is similar to that required in Europe, with the exception of, among other things, country-specific document requirements.

For other countries outside of the EU, such as countries in Eastern Europe, Latin America or Asia, the requirements governing the conduct of clinical trials, product licensing, pricing and reimbursement vary from country to country. In all cases, again, the clinical trials are conducted in accordance with cGCPs and the applicable regulatory requirements and the ethical principles that have their origin in the Declaration of Helsinki.

If we fail to comply with applicable foreign regulatory requirements, we may be subject to, among other things, fines, suspension or withdrawal of regulatory approvals, product recalls, seizure of products, operating restrictions and criminal prosecution.

Medicines can be authorized in the EU by using either the centralized authorization procedure or national authorization procedures.

• Centralized Procedure. Under the Centralized Procedure a so-called Community Marketing Authorization is issued by the European Commission, based on the opinion of the Committee for Medicinal Products for Human Use of the EMA. The Community Marketing Authorization is valid throughout the entire territory of the European Economic Area ("EEA") (which includes the 27 Member States of the EU plus Norway, Liechtenstein and Iceland). The Centralized Procedure is mandatory for certain types of products, such as biotechnology medicinal products, orphan medicinal products, and medicinal products indicated for the treatment of AIDS, cancer, neurodegenerative disorders, diabetes, auto-immune and viral diseases. The Centralized Procedure is optional for products containing a new active substance not yet authorized in the EEA, or for products that constitute a significant therapeutic, scientific or technical innovation or which are in the interest of public health in the EU.
• For medicines that do not fall within these categories, an applicant has the option of submitting an application for a centralized marketing authorization to the EMA, as long as the medicine concerned is a significant therapeutic, scientific or technical innovation, or if its authorization would be in the interest of public health.
• National Authorization Procedures. There are also two other possible routes to authorize medicinal products in several countries, which are available for investigational drug products that fall outside the scope of the centralized procedure:
• Decentralized Procedure. Using the Decentralized Procedure, an applicant may apply for simultaneous authorization in more than one EU country of medicinal products that have not yet been authorized in any EU country and that do not fall within the mandatory scope of the centralized procedure. Under the Decentralized Procedure the applicant chooses one country as Reference Member State. The regulatory authority of the Reference Member State will then be in charge of leading the assessment of the marketing authorization application.
• Mutual Recognition Procedure. In the Mutual Recognition Procedure, a medicine is first authorized in one EU Member State, in accordance with the national procedures of that country. Following this, further marketing authorizations can be sought from other EU countries in a procedure whereby the countries concerned agree to recognize the validity of the original, national marketing authorization.

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In the EU, upon receiving marketing authorization, new chemical entities generally receive eight years of data exclusivity and an additional two years of market exclusivity. If granted, data exclusivity prevents regulatory authorities in the EU from referencing the innovator's data to assess a generic application. During the additional two-year period of market exclusivity, a generic marketing authorization can be submitted, and the innovator's data may be referenced, but no generic product can be marketed until the expiration of the market exclusivity. However, there is no guarantee that a product will be considered by the EU's regulatory authorities to be a new chemical entity, and products may not qualify for data exclusivity.

We may also be subject to healthcare regulation and enforcement by the federal government and the states and foreign governments where we may market our product candidates, if approved.  These laws include, without limitation, state and federal anti-kickback, fraud and abuse, false claims, physician sunshine and privacy and security laws and regulations.

The federal Anti-Kickback Statute prohibits, among other things, any person from knowingly and willfully offering, soliciting, receiving or providing remuneration, directly or indirectly, to induce either the referral of an individual, for an item or service or the purchasing or ordering of a good or service, for which payment may be made under federal healthcare programs such as the Medicare and Medicaid programs.  The Anti-Kickback Statute is subject to evolving interpretations. In the past, the government has enforced the Anti-Kickback Statute to reach large settlements with healthcare companies based on sham consulting and other financial arrangements with physicians. A person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation. In addition, the government may assert that a claim including items or services resulting from a violation of the federal Anti-Kickback Statute constitutes a false or fraudulent claim for purposes of the federal False Claims Act. The majority of states also have anti-kickback laws which establish similar prohibitions and in some cases may apply to items or services reimbursed by any third-party payor, including commercial insurers.

Additionally, the civil False Claims Act prohibits knowingly presenting or causing the presentation of a false, fictitious or fraudulent claim for payment to the United States government. Actions under the False Claims Act may be brought by the Attorney General or as a qui tam action by a private individual in the name of the government. Violations of the False Claims Act can result in very significant monetary penalties and treble damages. The federal government is using the False Claims Act, and the accompanying threat of significant liability, in its investigation and prosecution of pharmaceutical and biotechnology companies throughout the United States, for example, in connection with the promotion of products for unapproved uses and other sales and marketing practices.  The government has obtained multi-million and multi-billion dollar settlements under the False Claims Act in addition to individual criminal convictions under applicable criminal statutes. Given the significant size of actual and potential settlements, it is expected that the government will continue to devote substantial resources to investigating healthcare providers' and manufacturers' compliance with applicable fraud and abuse laws.

The federal Health Insurance Portability and Accountability Act of 1996 ("HIPAA") also created new federal criminal statutes that prohibit among other actions, knowingly and willfully executing, or attempting to execute, a scheme to defraud any healthcare benefit program, including private third-party payors, knowingly and willfully embezzling or stealing from a healthcare benefit program, willfully obstructing a criminal investigation of a healthcare offense, and knowingly and willfully falsifying, concealing or covering up a material fact or making any materially false, fictitious or fraudulent statement in connection with the delivery of or payment for healthcare benefits, items or services. Similar to the federal Anti-Kickback Statute, a person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation.

There has also been a recent trend of increased federal and state regulation of payments made to physicians and other healthcare providers. The Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, (collectively, "the Affordable Care Act"), among other things, imposed new reporting requirements on drug manufacturers for payments made by them to physicians and teaching hospitals, as well as ownership and investment interests held by physicians and their immediate family members.  Failure to submit timely, accurately and completely the required information may result in civil monetary penalties of up to an aggregate of approximately $0.2 million per year (or up to an aggregate of $1.1 million per year for "knowing failures"), for all payments, transfers of value or ownership or investment interests that are not timely,

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accurately and completely reported in an annual submission.  Drug manufacturers are required to submit reports to the government by the 90th day of each calendar year.  Certain states also mandate implementation of compliance programs, impose restrictions on drug manufacturer marketing practices and/or require the tracking and reporting of marketing expenditures and pricing information as well as gifts, compensation and other remuneration to physicians.

We may also be subject to data privacy and security regulation by both the federal government and the states in which we conduct our business. HIPAA, as amended by the Health Information Technology and Clinical Health Act ("HITECH"), and their respective implementing regulations, including the final omnibus rule published on January 25, 2013, imposes specified requirements relating to the privacy, security and transmission of individually identifiable health information. Among other things, HITECH makes HIPAA's privacy and security standards directly applicable to "business associates," defined as independent contractors or agents of covered entities that create, receive, maintain or transmit protected health information in connection with providing a service for or on behalf of a covered entity. HITECH also increased the civil and criminal penalties that may be imposed against covered entities, business associates and possibly other persons, and gave state attorneys general new authority to file civil actions for damages or injunctions in federal courts to enforce the federal HIPAA laws and seek attorney's fees and costs associated with pursuing federal civil actions. In addition, state laws govern the privacy and security of health information in certain circumstances, many of which differ from each other in significant ways, thus complicating compliance efforts.

Sales of our product candidates, once approved, will depend, in part, on the extent to which the costs of our products will be covered by third-party payors, such as government health programs, private health insurers and managed care organizations. Third-party payors generally decide which drugs they will cover and establish certain reimbursement levels for such drugs. In particular, in the United States, private health insurers and other third-party payors often provide reimbursement for products and services based on the level at which the government (through the Medicare or Medicaid programs) provides reimbursement for such treatments. Patients who are prescribed treatments for their conditions and providers performing the prescribed services generally rely on third-party payors to reimburse all or part of the associated healthcare costs. Patients are unlikely to use our products unless coverage is provided and reimbursement is adequate to cover a significant portion of the cost of our products. Sales of our products and product candidates, if approved, will therefore depend substantially on the extent to which the costs of products and our product candidates will be paid by third-party payors. Additionally, the market for our products and product candidates will depend significantly on access to third-party payors' formularies without prior authorization, step therapy, or other limitations such as approved lists of treatments for which third-party payors provide coverage and reimbursement. Additionally, coverage and reimbursement for therapeutic products can differ significantly from payor to payor. One third-party payor's decision to cover a particular medical product or service does not ensure that other payors will also provide coverage for the medical product or service, or will provide coverage at an adequate reimbursement rate. As a result, the coverage determination process will require us to provide scientific and clinical support for the use of our products to each payor separately and will be a time-consuming process.

In addition, the United States government, state legislatures and foreign governments have continued implementing cost-containment programs, including price controls, restrictions on coverage and reimbursement and requirements for substitution of generic products. Adoption of price controls and cost-containment measures, and adoption of more restrictive policies in jurisdictions with existing controls and measures, could further limit our future net revenue and results. Decreases in third-party reimbursement for our products and product candidates or a decision by a third-party payor to not cover our products or product candidates could reduce physician usage of our products and product candidates, if approved, and have a material adverse effect on our sales, results of operations and financial condition.

In the United States and foreign jurisdictions, there have been a number of legislative and regulatory changes to the healthcare system that could affect our future results of operations. There have been and continue to be a number of initiatives at the United States federal and state levels that seek to reduce healthcare costs.

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In particular, in the United States, the Affordable Care Act has had, and is expected to continue to have, a significant impact on the healthcare industry. The Affordable Care Act was designed to expand coverage for the uninsured while at the same time containing overall healthcare costs. The Affordable Care Act, among other things, addressed a new methodology by which rebates owed by manufacturers under the Medicaid Drug Rebate Program are calculated for drugs that are inhaled, infused, instilled, implanted or injected, increased the minimum Medicaid rebates owed by manufacturers under the Medicaid Drug Rebate Program and extended the rebate program to individuals enrolled in Medicaid managed care organizations, established annual fees and taxes on manufacturers of certain branded prescription drugs, and established a new Medicare Part D coverage gap discount program, in which manufacturers must agree to offer 50% point-of-sale discounts, which, through subsequent legislative amendments, was increased to 70%, off negotiated prices of applicable brand drugs to eligible beneficiaries during their coverage gap period, as a condition for the manufacturer's outpatient drugs to be covered under Medicare Part D. Substantial new provisions affecting compliance were also enacted, which may require us to modify our business practices with healthcare providers and entities.

Since its enactment, there have been judicial and Congressional challenges to certain aspects of the Affordable Care Act. We expect that the current presidential administration and U.S. Congress will likely continue to seek to modify, repeal, or otherwise invalidate all, or certain provisions of, the Affordable Care Act. Most recently, the Tax Cuts and Jobs Act was enacted, which, among other things, removes penalties for not complying with Affordable Care Act's individual mandate to carry health insurance. There is still uncertainty with respect to the impact President Biden's administration and the U.S. Congress may have, if any, and any changes will likely take time to unfold, and could have an impact on coverage and reimbursement for healthcare items and services covered by plans that were authorized by the Affordable Care Act.

In addition, other legislative changes have been proposed and adopted since the Affordable Care Act was enacted. These changes include aggregate reductions to Medicare payments to providers of 2% per fiscal year, which went into effect on April 1, 2013 and, due to subsequent legislative amendments to the statute, will stay in effect through 2025 unless additional Congressional action is taken. Additionally, in January 2013, the American Taxpayer Relief Act of 2012 was signed into law, which, among other things, further reduced Medicare payments to several types of providers and increased the statute of limitations period for the government to recover overpayments to providers from three to five years. Recently there has been heightened governmental scrutiny over the manner in which manufacturers set prices for their marketed products, which has resulted in several Congressional inquiries and proposed bills designed to, among other things, reform government program reimbursement methodologies. Individual states in the United States have also become increasingly active in implementing regulations designed to control pharmaceutical product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing. We expect that additional state and federal healthcare reform measures will be adopted in the future, any of which could limit the amounts that federal and state governments will pay for healthcare products and services, which could result in reduced demand for our product candidates or additional pricing pressures.

As of March 4, 2021, we had 10 employees, 9 of which are full-time employees, and all of whom are in the United States. Our organization will rely primarily on outsourcing research, development and clinical trial activities, and manufacturing operations, as well as other functions critical to our business. We believe this approach enhances our ability to focus on our core product opportunities, allocate resources efficiently to different projects and allocate internal resources more effectively. None of our employees are represented by a collective bargaining agreement. We believe that we have a good relationship with our employees.

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Corporate Information

We were incorporated under the laws of the State of Nevada in 1987, as NexMed, Inc. On September 10, 2010, we changed our name to "Apricus Biosciences, Inc." On January 24, 2019, we completed the Merger with STI (formerly known as Seelos Therapeutics, Inc.), a Delaware corporation, and, upon completion of the Merger, we changed our name to "Seelos Therapeutics, Inc." Shares of our common stock commenced trading on the Nasdaq Capital Market under the ticker symbol "SEEL" as of market open on January 24, 2019.

We file annual, quarterly and current reports, proxy statements and other information with the SEC, and we have an Internet website address at http://www.seelostherapeutics.com. We make available free of charge on our Internet website address our annual report 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 Sections 13(a) or 15(d) of the Exchange Act as well as our proxy statements as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. You may also obtain copies of such documents from the SEC's website at http://www.sec.gov.

Below is a summary of the principal factors that make an investment in our securities speculative or risky. This summary does not address all of the risks that we face. Additional discussion of the risks summarized in this risk factor summary, and other risks that we face, can be found below and should be carefully considered, together with all of the other information appearing in or incorporated by reference into this prospectus, the applicable prospectus supplement and any related free writing prospectus before making investment decisions regarding the offered securities.

• We are a clinical-stage company, we have a very limited operating history, are not currently profitable, do not expect to become profitable in the near future and may never become profitable.
• We are dependent on the success of one or more of our current product candidates and we cannot be certain that any of them will receive regulatory approval or be commercialized.
• If development of our product candidates does not produce favorable results, or encounters challenges, we and our collaborators, if any, may be unable to commercialize these products.
• We expect to continue to incur significant research and development expenses, which may make it difficult for us to attain profitability.
• Given our lack of current cash flow, we will need to raise additional capital; however, it may be unavailable to us or, even if capital is obtained, may cause dilution or place significant restrictions on our ability to operate our business. If we fail to raise the necessary additional capital, we may be unable to complete the development and commercialization of our product candidates, or continue our development programs.
• Our product candidates may cause undesirable side effects that could delay or prevent their regulatory approval or commercialization or have other significant adverse implications on our business, financial condition and results of operations.
• Delays in the commencement or completion of clinical trials could result in increased costs to us and delay our ability to establish strategic collaborations.
• A pandemic, epidemic or outbreak of an infectious disease, such as COVID-19, may materially and adversely affect our business and operations.
• Results of earlier clinical trials may not be predictive of the results of later-stage clinical trials.
• We intend to rely on third parties to conduct our preclinical studies and clinical trials and perform other tasks. If these third parties do not successfully carry out their contractual duties, meet expected deadlines, or comply with regulatory requirements, we may not be able to obtain regulatory approval for or commercialize our product candidates and our business, financial condition and results of operations could be substantially harmed.

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• Our product candidates are subject to extensive regulation under the FDA, the EMA or comparable foreign authorities, which can be costly and time consuming, cause unanticipated delays or prevent the receipt of the required approvals to commercialize our product candidates.
• If our competitors have product candidates that are approved faster, marketed more effectively, are better tolerated, have a more favorable safety profile or are demonstrated to be more effective than ours, our commercial opportunity may be reduced or eliminated.
• We rely completely on third parties to manufacture our preclinical and clinical drug supplies, and our business, financial condition and results of operations could be harmed if those third parties fail to provide us with sufficient quantities of drug product, or fail to do so at acceptable quality levels or prices.
• The commercial success of our product candidates depends upon their market acceptance among physicians, patients, healthcare payors and the medical community.
• If we fail to retain current members of our senior management and scientific personnel, or to attract and keep additional key personnel, we may be unable to successfully develop or commercialize our product candidates.
• We may not be successful in obtaining or maintaining necessary rights to our product candidates through acquisitions and in-licenses.
• If we fail to comply with our obligations in the agreements under which we in-license intellectual property and other rights from third parties or otherwise experience disruptions to our business relationships with our licensors, we could lose intellectual property rights that are important to our business.
• We may not be able to protect our proprietary or licensed technology in the marketplace.
• The market price of our common stock is expected to be volatile.

We are a clinical-stage biopharmaceutical company. Since our incorporation, we have focused primarily on the development and acquisition of clinical-stage therapeutic candidates, which has not changed as a result of the completion of the business combination between Apricus Biosciences, Inc., a Nevada corporation ("Apricus"), and Seelos Therapeutics, Inc., a Delaware corporation ("STI"), in accordance with the terms of the Agreement and Plan of Merger and Reorganization entered into on July 30, 2018, pursuant to which (i) a subsidiary of Apricus merged with and into STI, with STI (renamed as "Seelos Corporation") continuing as a wholly owned subsidiary of Apricus and the surviving corporation of the merger and (ii) Apricus was renamed as "Seelos Therapeutics, Inc." (the "Merger"). All of our therapeutic candidates are in the clinical development stage and none of our pipeline therapeutic candidates have been approved for marketing or are being marketed or commercialized.

As a result, we have no meaningful historical operations upon which to evaluate our business and prospects and have not yet demonstrated an ability to obtain marketing approval for any of our product candidates or successfully overcome the risks and uncertainties frequently encountered by companies in the biopharmaceutical industry. We also have generated minimal revenues from collaboration and licensing agreements and no revenues from product sales to date and continue to incur significant research and development and other expenses. As a result, we have not been profitable and have incurred significant operating losses in every reporting period since our inception. We have incurred an accumulated deficit of $75.2 million from our inception through December 31, 2020.

For the foreseeable future, we expect to continue to incur losses, which will increase significantly from historical levels as we expand our drug development activities, seek partnering and/or regulatory approvals for our product candidates and begin to commercialize them if they are approved by the U.S. Food and Drug Administration (the "FDA") the European Medicines Agency (the "EMA") or comparable foreign authorities. Even if we succeed in developing and commercializing one or more product candidates, we may never become profitable.

We have spent significant time, money and effort on the licensing and development of our core assets, SLS-002, SLS-005 and SLS-006 and our other earlier-stage assets, SLS- 004, SLS-007, SLS-008, SLS-010 and SLS-012. To date, no pivotal clinical trials designed to provide clinically and statistically significant proof of efficacy, or to provide sufficient evidence of safety to justify approval, have been completed with any of our pipeline product candidates. All of our product candidates will require

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additional development, including clinical trials as well as further preclinical studies to evaluate their toxicology, carcinogenicity and pharmacokinetics and optimize their formulation, and regulatory clearances before they can be commercialized. Positive results obtained during early development do not necessarily mean later development will succeed or that regulatory clearances will be obtained. Our drug development efforts may not lead to commercial drugs, either because our product candidates may fail to be safe and effective or because we have inadequate financial or other resources to advance our product candidates through the clinical development and approval processes. If any of our product candidates fail to demonstrate safety or efficacy at any time or during any phase of development, we would experience potentially significant delays in, or be required to abandon, development of the product candidate.

We do not anticipate that any of our current product candidates will be eligible to receive regulatory approval from the FDA, the EMA or comparable foreign authorities and begin commercialization for a number of years, if ever. Even if we ultimately receive regulatory approval for any of these product candidates, we or our potential future partners, if any, may be unable to commercialize them successfully for a variety of reasons. These include, for example, the availability of alternative treatments, lack of cost-effectiveness, the cost of manufacturing the product on a commercial scale and competition with other drugs. The success of our product candidates may also be limited by the prevalence and severity of any adverse side effects. If we fail to commercialize one or more of our current product candidates, we may be unable to generate sufficient revenues to attain or maintain profitability, and our financial condition and stock price may decline.

To receive regulatory approval for the commercialization of our core assets, SLS-002, SLS-005 and SLS-006 and our earlier-stage assets, SLS-004, SLS-007, SLS-008, SLS- 010 and SLS-012, or any other product candidates that we may develop, adequate and well-controlled clinical trials must be conducted to demonstrate safety and efficacy in humans to the satisfaction of the FDA, the EMA and comparable foreign authorities. In order to support marketing approval, these agencies typically require successful results in one or more Phase III clinical trials, which our current product candidates have not yet reached and may never reach. The development process is expensive, can take many years and has an uncertain outcome. Failure can occur at any stage of the process. We may experience numerous unforeseen events during, or as a result of, the development process that could delay or prevent commercialization of our current or future product candidates, including the following:

• clinical trials may produce negative or inconclusive results;
• preclinical studies conducted with product candidates during clinical development to, among other things, evaluate their toxicology, carcinogenicity and pharmacokinetics and optimize their formulation may produce unfavorable results;
• we our or contract manufacturers may encounter manufacturing challenges or FDA may raise concerns regarding Chemistry, Manufacturing, and Controls (CMC) data or GMP compliance, or biocompatibility or drug-device interaction concerns for our combination product candidates;
• patient recruitment and enrollment in clinical trials may be slower than we anticipate;
• costs of development may be greater than we anticipate;
• our product candidates may cause undesirable side effects that delay or preclude regulatory approval or limit their commercial use or market acceptance, if approved;
• collaborators who may be responsible for the development of our product candidates may not devote sufficient resources to these clinical trials or other preclinical studies of these candidates or conduct them in a timely manner; or
• we may face delays in obtaining regulatory approvals to commence one or more clinical trials.

Success in early development does not mean that later development will be successful because, for example, product candidates in later-stage clinical trials may fail to demonstrate sufficient safety and efficacy despite having progressed through initial clinical trials.

We have licensed or acquired all of the intellectual property related to our product candidates from third parties. All clinical trials, preclinical studies and other analyses performed to date with respect to our product candidates have been conducted by their original owners. Therefore, as a company, we have limited experience in conducting clinical trials for our product candidates. Since our experience with our product candidates is limited, we will need to train our existing personnel and hire additional personnel in order to successfully administer and manage our clinical trials and other studies as planned, which may result in delays in completing such planned clinical trials and preclinical studies. Moreover, to date our product candidates have been tested in less than the number of patients that will likely need to be studied to obtain regulatory approval. The data collected from clinical trials with larger patient populations may not demonstrate sufficient safety and efficacy to support regulatory approval of these product candidates.

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We currently do not have strategic collaborations in place for clinical development of any of our current product candidates, except for our collaborative agreement with Team Sanfilippo Foundation ("TSF"), which we assumed in connection with the asset purchase agreement with Bioblast Pharma Ltd. for IV Trehalose, which is now known as SLS-005. Therefore, in the future, we or any potential future collaborative partner will be responsible for establishing the targeted endpoints and goals for development of our product candidates. These targeted endpoints and goals may be inadequate to demonstrate the safety and efficacy levels required for regulatory approvals. Even if we believe data collected during the development of our product candidates are promising, such data may not be sufficient to support marketing approval by the FDA, the EMA or comparable foreign authorities. Further, data generated during development can be interpreted in different ways, and the FDA, the EMA or comparable foreign authorities may interpret such data in different ways than us or our collaborators. Our failure to adequately demonstrate the safety and efficacy of our product candidates would prevent our receipt of regulatory approval, and ultimately the potential commercialization of these product candidates.

Since we do not currently possess the resources necessary to independently develop and commercialize our product candidates or any other product candidates that we may develop, we may seek to enter into collaborative agreements to assist in the development and potential future commercialization of some or all of these assets as a component of our strategic plan. However, our discussions with potential collaborators may not lead to the establishment of collaborations on acceptable terms, if at all, or it may take longer than expected to establish new collaborations, leading to development and potential commercialization delays, which would adversely affect our business, financial condition and results of operations.

We expect to expend substantial funds in research and development, including preclinical studies and clinical trials of our product candidates, and to manufacture and market any product candidates in the event they are approved for commercial sale. We also may need additional funding to develop or acquire complementary companies, technologies and assets, as well as for working capital requirements and other operating and general corporate purposes. Moreover, our planned increases in staffing will dramatically increase our costs in the near and long-term.

However, our spending on current and future research and development programs and product candidates for specific indications may not yield any commercially viable products. Due to our limited financial and managerial resources, we must focus on a limited number of research programs and product candidates and on specific indications. Our resource allocation decisions may cause us to fail to capitalize on viable commercial products or profitable market opportunities.

Because the successful development of our product candidates is uncertain, we are unable to precisely estimate the actual funds we will require to develop and potentially commercialize them. In addition, we may not be able to generate sufficient revenue, even if we are able to commercialize any of our product candidates, to become profitable.

Since we will be unable to generate sufficient, if any, cash flow to fund our operations for the foreseeable future, we will need to seek additional equity or debt financing to provide the capital required to maintain or expand our operations.

As of December 31, 2020, we had a cash balance of approximately $15.7 million. On January 28, 2021, we completed an underwritten public offering pursuant to which we sold 17,530,488 shares of our common stock at a price to the public of $2.05 per share, which included the exercise in full by the underwriter of its option to purchase up to 2,286,585 additional shares of common stock. The net proceeds to us from the offering were approximately $33.5 million, after deducting underwriting discounts and commissions and other estimated offering expenses payable by us. We used $3.8 million of the net proceeds from the offering for the partial repayment of certain outstanding convertible promissory notes.

As a result of our recurring losses from operations, there is uncertainty regarding our ability to maintain liquidity sufficient to operate our business effectively, which raises substantial doubt about our ability to continue as a going concern. If we are unsuccessful in our efforts to raise outside financing, we may be required to significantly reduce or cease operations. The report of our independent registered public accounting firm on our audited financial statements for the year ended December 31, 2020 included a "going concern" explanatory paragraph indicating that our recurring losses from operations raise substantial doubt about our ability to continue as a going concern.

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We currently have an effective shelf registration statement on Form S-3 filed with the SEC. We may use the shelf registration statement on Form S-3 of which this prospectus forms a part to offer from time to time any combination of debt securities, common and preferred stock and warrants, and, as of the date hereof, a total of $168.7 million of securities remains available for issuance pursuant to the shelf registration statement.

In addition, the impact of the COVID-19 pandemic on the global financial markets may reduce our ability to access capital, which could negatively affect our liquidity and ability to continue as a going concern.

There can be no assurance that we will be able to raise sufficient additional capital on acceptable terms or at all. If such additional financing is not available on satisfactory terms, or is not available in sufficient amounts, we may be required to delay, limit or eliminate the development of business opportunities and our ability to achieve our business objectives, our competitiveness, and our business, financial condition and results of operations will be materially adversely affected. In addition, we may be required to grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves. Our inability to fund our business could lead to the loss of your investment.

Our future capital requirements will depend on many factors, including, but not limited to:

• the scope, rate of progress, results and cost of our clinical trials, preclinical studies and other related activities;
• our ability to establish and maintain strategic collaborations, licensing or other arrangements and the financial terms of such arrangements;
• the timing of, and the costs involved in, obtaining regulatory approvals for any of our current or future product candidates;
• the number and characteristics of the product candidates we seek to develop or commercialize;
• the cost of manufacturing clinical supplies, and establishing commercial supplies, of our product candidates;
• the cost of commercialization activities if any of our current or future product candidates are approved for sale, including marketing, sales and distribution costs;
• the expenses needed to attract and retain skilled personnel;
• the costs associated with being a public company;
• the amount of revenue, if any, received from commercial sales of our product candidates, should any of our product candidates receive marketing approval; and
• the costs involved in preparing, filing, prosecuting, maintaining, defending and enforcing possible patent claims, including litigation costs and the outcome of any such litigation.

If we raise additional capital by issuing equity securities, the percentage ownership of our existing stockholders may be reduced, and accordingly these stockholders may experience substantial dilution. We may also issue equity securities that provide for rights, preferences and privileges senior to those of our common stock. Given our need for cash and that equity issuances are the most common type of fundraising for similarly situated companies, the risk of dilution is particularly significant for our stockholders. In addition, debt financing may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends and may be secured by all or a portion of our assets.  Our inability to raise capital when needed would harm our business, financial condition and results of operations, and could cause our stock price to decline or require that we wind down our operations altogether.

Undesirable side effects observed in clinical trials or in supportive preclinical studies with our product candidates could interrupt, delay or halt their development and could result in the denial of regulatory approval by the FDA, the EMA or comparable foreign authorities for any or all targeted indications or adversely affect the marketability of any such product candidates that receive regulatory approval. In turn, this could eliminate or limit our ability to commercialize our product candidates.

Our product candidates may exhibit adverse effects in preclinical toxicology studies and adverse interactions with other drugs. There are also risks associated with additional requirements the FDA, the EMA or comparable foreign authorities may impose for marketing approval with regard to a particular disease.

Our product candidates may require a risk management program that could include patient and healthcare provider education, usage guidelines, appropriate promotional activities, a post-marketing observational study, and ongoing safety and reporting mechanisms, among other requirements. Prescribing could be limited to physician specialists or physicians trained in the use of

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the drug, or could be limited to a more restricted patient population. Any risk management program required for approval of our product candidates could potentially have an adverse effect on our business, financial condition and results of operations.

Undesirable side effects involving our product candidates may have other significant adverse implications on our business, financial condition and results of operations. For example:

• we may be unable to obtain additional financing on acceptable terms, if at all;
• our collaborators may terminate any development agreements covering these product candidates;
• if any development agreements are terminated, we may determine not to further develop the affected product candidates due to resource constraints and may not be able to establish additional collaborations for their further development on acceptable terms, if at all;
• if we were to later continue the development of these product candidates and receive regulatory approval, earlier findings may significantly limit their marketability and thus significantly lower our potential future revenues from their commercialization;
• we may be subject to product liability or stockholder litigation; and
• we may be unable to attract and retain key employees.

In addition, if any of our product candidates receive marketing approval and we or others later identify undesirable side effects caused by the product:

• regulatory authorities may withdraw their approval of the product, or we or our partners may decide to cease marketing and sale of the product voluntarily;
• we may be required to change the way the product is administered, conduct additional clinical trials or preclinical studies regarding the product, change the labeling of the product, or change the product's manufacturing facilities; and
• our reputation may suffer.

Any of these events could prevent us from achieving or maintaining market acceptance of the affected product and could substantially increase the costs and expenses of commercializing the product, which in turn could delay or prevent us from generating significant revenues from the sale of the product.

We intend to use our technology, including our licensed technology, knowledge and expertise to develop novel drugs to address some of the world's most widespread and costly central nervous system, respiratory and other disorders, including orphan indications. We intend to expand our existing pipeline of core assets by advancing drug compounds from current ongoing discovery programs into clinical development. However, the process of researching and discovering drug compounds is expensive, time-consuming and unpredictable. Data from our current preclinical programs may not support the clinical development of our lead compounds or other compounds from these programs, and we may not identify any additional drug compounds suitable for recommendation for clinical development. Moreover, any drug compounds we recommend for clinical development may not demonstrate, through preclinical studies, indications of safety and potential efficacy that would support advancement into clinical trials. Such findings would potentially impede our ability to maintain or expand our clinical development pipeline. Our ability to identify new drug compounds and advance them into clinical development also depends upon our ability to fund our research and development operations, and we cannot be certain that additional funding will be available on acceptable terms, or at all.

Delays in the commencement or completion of clinical trials could significantly impact our drug development costs. We do not know whether planned clinical trials will begin on time or be completed on schedule, if at all. The commencement of clinical trials can be delayed for a variety of reasons, including, but not limited to, delays related to:

• obtaining regulatory approval to commence one or more clinical trials;
• reaching agreement on acceptable terms with prospective third-party contract research organizations ("CROs") and clinical trial sites;
• manufacturing sufficient quantities of a product candidate or other materials necessary to conduct clinical trials;
• obtaining institutional review board approval to conduct one or more clinical trials at a prospective site;
• recruiting and enrolling patients to participate in one or more clinical trials; and

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• the failure of our collaborators to adequately resource our product candidates due to their focus on other programs or as a result of general market conditions.

In addition, once a clinical trial has begun, it may be suspended or terminated by us, our collaborators, the institutional review boards or data safety monitoring boards charged with overseeing our clinical trials, the FDA, the EMA or comparable foreign authorities due to a number of factors, including:

• failure to conduct the clinical trial in accordance with regulatory requirements or clinical protocols;
• inspection of the clinical trial operations or clinical trial site by the FDA, the EMA or comparable foreign authorities resulting in the imposition of a clinical hold;
• unforeseen safety issues; or
• lack of adequate funding to continue the clinical trial.

If we experience delays in the completion, or termination, of any clinical trial of our product candidates, the commercial prospects of our product candidates will be harmed, and our ability to commence product sales and generate product revenues from any of our product candidates will be delayed. In addition, any delays in completing our clinical trials will increase our costs and slow down our product candidate development and approval process. Delays in completing our clinical trials could also allow our competitors to obtain marketing approval before we do or shorten the patent protection period during which we may have the exclusive right to commercialize our product candidates. Any of these occurrences may harm our business, financial condition and prospects significantly. In addition, many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval of our product candidates.

On March 11, 2020, the World Health Organization declared COVID-19 a pandemic. The COVID-19 pandemic is affecting the United States and global economies and may affect our operations and those of third parties on which we rely, including by causing disruptions in the supply of our product candidates and the conduct of future clinical trials. In addition, the COVID-19 pandemic may affect the operations of the FDA and other health authorities, which could result in delays of reviews and approvals, including with respect to our product candidates. Additionally, while the potential economic impact brought by, and the duration of the COVID-19 pandemic is difficult to assess or predict, the impact of the COVID-19 pandemic on the global financial markets may reduce our ability to access capital, which could negatively impact our short-term and long-term liquidity. In addition, the loss of any of our employees as a result of COVID-19 or another pandemic, may have a material adverse effect on our operations. The ultimate impact of the COVID-19 pandemic is highly uncertain and subject to change. We do not yet know the full extent of potential delays or impacts on our business, financing or clinical trial activities or on healthcare systems or the global economy as a whole. However, these effects could have a material impact on our liquidity, capital resources, operations and business and those of the third parties on which we rely.

The results of preclinical studies and early clinical trials of product candidates may not be predictive of the results of later-stage clinical trials. Product candidates in later stages of clinical trials may fail to show the desired safety and efficacy results despite having progressed through preclinical studies and initial clinical trials. Many companies in the biopharmaceutical industry have suffered significant setbacks in advanced clinical trials due to adverse safety profiles or lack of efficacy, notwithstanding promising results in earlier studies. Similarly, our future clinical trial results may not be successful for these or other reasons.

This product candidate development risk is heightened by any changes in the planned clinical trials compared to the completed clinical trials. As product candidates are developed through preclinical to early to late stage clinical trials towards approval and commercialization, it is customary that various aspects of the development program, such as manufacturing and methods of administration, are altered along the way in an effort to optimize processes and results. While these types of changes are common and are intended to optimize the product candidates for late stage clinical trials, approval and commercialization, such changes carry the risk that they will not achieve these intended objectives. In addition, nonclinical studies may be requested or required even after clinical trials have been commenced or completed.

Any of these changes could make the results of our planned clinical trials or other future clinical trials we may initiate less predictable and could cause our product candidates to perform differently, including causing toxicities, which could delay completion of our clinical trials, delay approval of our product candidates, and/or jeopardize our ability to commence product sales and generate revenues.

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If we experience delays in the enrollment of patients in our clinical trials, our receipt of necessary regulatory approvals could be delayed or prevented.

We may not be able to initiate or continue clinical trials for our product candidates if we are unable to locate and enroll a sufficient number of eligible patients to participate in these trials as required by the FDA or other regulatory authorities. In addition, the COVID-19 pandemic may result in a reduction of patient enrollment, a loss of patient enrollment and other delays affecting our clinical trials.  Patient enrollment, a significant factor in the timing of clinical trials, is affected by many factors, including the size and nature of the patient population, the proximity of patients to clinical sites, the eligibility criteria for the trial, the design of the clinical trial, competing clinical trials and clinicians' and patients' perceptions as to the potential advantages of the drug being studied in relation to other available therapies, including any new drugs that may be approved for the indications we are investigating.

If we fail to enroll and maintain the number of patients for which the clinical trial was designed, the statistical power of that clinical trial may be reduced, which would make it harder to demonstrate that the product candidate being tested in such clinical trial is safe and effective. Additionally, enrollment delays in our clinical trials may result in increased development costs for our product candidates, which would cause the value of our company to decline and limit our ability to obtain additional financing. Our inability to enroll a sufficient number of patients for any of our current or future clinical trials would result in significant delays or may require us to abandon one or more clinical trials altogether.

We intend to rely upon third-party CROs, medical institutions, clinical investigators and contract laboratories to monitor and manage data for our ongoing preclinical and clinical programs. Nevertheless, we maintain responsibility for ensuring that each of our clinical trials and preclinical studies is conducted in accordance with the applicable protocol, legal, regulatory, and scientific standards and our reliance on these third parties does not relieve us of our regulatory responsibilities. We and our CROs and other vendors are required to comply with current requirements on good manufacturing practices ("cGMP") good clinical practices ("GCP") and good laboratory practice ("GLP"), which are a collection of laws and regulations enforced by the FDA, the EMA and comparable foreign authorities for all of our product candidates in clinical development. Regulatory authorities enforce these regulations through periodic inspections of preclinical study and clinical trial sponsors, principal investigators, preclinical study and clinical trial sites, and other contractors. If we or any of our CROs or vendors fails to comply with applicable regulations, the data generated in our preclinical studies and clinical trials may be deemed unreliable and the FDA, the EMA or comparable foreign authorities may require us to perform additional preclinical studies and clinical trials before approving our marketing applications. We cannot assure you that upon inspection by a given regulatory authority, such regulatory authority will determine that any of our clinical trials comply with GCP regulations. In addition, our clinical trials must be conducted with products produced consistent with cGMP regulations. Our failure to comply with these regulations may require us to repeat clinical trials, which would delay the development and regulatory approval processes.

We may not be able to enter into arrangements with CROs on commercially reasonable terms, or at all. In addition, our CROs will not be our employees, and except for remedies available to us under our agreements with such CROs, we will not be able to control whether or not they devote sufficient time and resources to our ongoing preclinical and clinical programs. If CROs do not successfully carry out their contractual duties or obligations or meet expected deadlines, if they need to be replaced or if the quality or accuracy of the data they obtain is compromised due to the failure to adhere to our protocols, regulatory requirements, or for other reasons, our clinical trials may be extended, delayed or terminated and we may not be able to obtain regulatory approval for or successfully commercialize our product candidates. CROs may also generate higher costs than anticipated. As a result, our business, financial condition and results of operations and the commercial prospects for our product candidates could be materially and adversely affected, our costs could increase, and our ability to generate revenue could be delayed.

Switching or adding additional CROs, medical institutions, clinical investigators or contract laboratories involves additional cost and requires management time and focus. In addition, there is a natural transition period when a new CRO commences work replacing a previous CRO. As a result, delays occur, which can materially impact our ability to meet our desired clinical development timelines. There can be no assurance that we will not encounter similar challenges or delays in the future or that these delays or challenges will not have a material adverse effect on our business, financial condition or results of operations.

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The clinical development, manufacturing, labeling, storage, record-keeping, advertising, promotion, export, marketing and distribution of our product candidates are subject to extensive regulation by the FDA and other U.S. regulatory agencies, the EMA or comparable authorities in foreign markets. In the U.S., neither we nor our collaborators are permitted to market our product candidates until we or our collaborators receive approval of a new drug application ("NDA") from the FDA or receive similar approvals abroad. The process of obtaining these approvals is expensive, often takes many years, and can vary substantially based upon the type, complexity and novelty of the product candidates involved. Approval policies or regulations may change and may be influenced by the results of other similar or competitive products, making it more difficult for us to achieve such approval in a timely manner or at all. Any guidance that may result from recent FDA advisory panel discussions may make it more expensive to develop and commercialize such product candidates. In addition, as a company, we have not previously filed NDAs with the FDA or filed similar applications with other foreign regulatory agencies. This lack of experience may impede our ability to obtain FDA or other foreign regulatory agency approval in a timely manner, if at all, for our product candidates for which development and commercialization is our responsibility.

Despite the time and expense invested, regulatory approval is never guaranteed. The FDA, the EMA or comparable foreign authorities can delay, limit or deny approval of a product candidate for many reasons, including:

• a product candidate may not be deemed safe or effective;
• agency officials of the FDA, the EMA or comparable foreign authorities may not find the data from non-clinical or preclinical studies and clinical trials generated during development to be sufficient;
• the FDA, the EMA or comparable foreign authorities may not approve our third-party manufacturers' processes or facilities; or
• the FDA, the EMA or a comparable foreign authority may change its approval policies or adopt new regulations.
• Our inability to obtain these approvals would prevent us from commercializing our product candidates.

For our lead product candidate (SLS-002) we are pursuing development in order to seek potential U.S. Food and Drug Administration (the "FDA") approval under an abbreviated regulatory pathway called a 505(b)(2) NDA, which permits the filing of an NDA where at least some of the information required for approval comes from studies that were not conducted by or for the applicant and for which the applicant has not obtained a right of reference. We may also pursue this pathway for other of our product candidates. Section 505(b)(2), if applicable to us for a particular product candidate, would allow an NDA we submit to the FDA to rely, in part, on data in the public domain or the FDA's prior conclusions regarding the safety and effectiveness of approved compounds, which could expedite the development program for a product candidate by potentially decreasing the amount of clinical data that we would need to generate in order to obtain FDA approval.

Even if the FDA allows us to rely on the 505(b)(2) regulatory pathway, there is no assurance that such marketing approval will be obtained in a timely manner, or at all. The FDA may require us to perform additional nonclinical studies and clinical trials, and conduct other development work, to support any change from the reference listed drug (including with respect to the route of administration and drug delivery method and device), which presents uncertainty about the data that may ultimately be necessary and could be time-consuming and substantially delay our application for or potential receipt of marketing approval.

Even if we are able to utilize the 505(b)(2) regulatory pathway, a drug approved via this pathway may be subject to the same post-approval limitations, conditions and requirements as any other drug, including, for example a Risk Evaluation and Mitigation Strategy ("REMS"), which we anticipate will be required for our lead product candidate.

Also, as has been the experience of others in our industry, our competitors may file citizens' petitions with the FDA to contest approval of our NDA, which may delay or even prevent the FDA from approving any NDA that we submit under the 505(b)(2) regulatory pathway. If an FDA decision or action relative to our product candidate, or the FDA's interpretation of Section 505(b)(2) more generally, is successfully challenged, it could result in delays or even prevent the FDA from approving a 505(b)(2) application for such product candidate.

In addition, we may face Hatch-Waxman litigation in relation to our NDAs submitted under the 505(b)(2) regulatory pathway, which may further delay or prevent the approval of our product candidate. The pharmaceutical industry is highly competitive, and 505(b)(2) NDAs are subject to special requirements designed to protect the patent rights of sponsors of previously approved drugs that are referenced in a 505(b)(2) NDA. If the previously approved drugs referenced in an applicant's 505(b)(2) NDA are protected by patent(s) listed in the FDA's Approved Drug Products with Therapeutic Equivalence Evaluations publication, or the Orange Book, the 505(b)(2) applicant is required to make a claim after filing its NDA that each such patent is invalid, unenforceable or will not be infringed. The patent holder may thereafter bring suit for patent infringement, which will

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trigger a mandatory 30-month delay (or the shorter of dismissal of the lawsuit or expiration of the patent(s)) in approval of the 505(b)(2) NDA application.

If the FDA determines that our 505(b)(2) regulatory pathway is not viable for SLS-002 or any other applicable product candidate for any reason, we would need to reconsider our plans and might not be able to commercialize any such product candidate in a cost-efficient manner, or at all. If we were to pursue approval under the 505(b)(1) NDA pathway, we would be subject to more extensive requirements and risks such as conducting additional clinical trials, providing additional data and information or meeting additional standards for marketing approval. As a result, the time and financial resources required to obtain marketing approval for our product candidates would likely increase substantially and further complications and risks associated with our product candidates may arise. Also, new competing products may reach the market faster than ours, which may materially and adversely affect our competitive position, business and prospects.

In order to market any products outside of the U.S., we must establish and comply with numerous and varying regulatory requirements of other countries regarding safety and efficacy. Approval procedures vary among countries and can involve additional product testing and additional administrative review periods. The time required to obtain approval in other countries might differ from that required to obtain FDA approval. The regulatory approval process in other countries may include all of the risks detailed above regarding FDA approval in the U.S. as well as other risks. Regulatory approval in one country does not ensure regulatory approval in another, but a failure or delay in obtaining regulatory approval in one country may have a negative effect on the regulatory process in others. Failure to obtain regulatory approval in other countries or any delay seeking or obtaining such approval would impair our ability to develop foreign markets for our product candidates.

If any of our product candidates receive regulatory approval, the FDA, the EMA or comparable foreign authorities may still impose significant restrictions on the indicated uses or marketing of the product candidates or impose ongoing requirements for potentially costly post-approval studies and trials. In addition, regulatory agencies subject a product, our manufacturer and the manufacturer's facilities to continual review and periodic inspections. If a regulatory agency discovers previously unknown problems with a product, including adverse events of unanticipated severity or frequency, or problems with the facility where the product is manufactured, a regulatory agency may impose restrictions on that product, our collaborators or us, including requiring withdrawal of the product from the market. Our product candidates will also be subject to ongoing FDA, the EMA or comparable foreign authorities' requirements for the labeling, packaging, storage, advertising, promotion, record-keeping and submission of safety and other post-market information on the drug. If our product candidates fail to comply with applicable regulatory requirements, a regulatory agency may:

• issue warning letters or other notices of possible violations;
• impose civil or criminal penalties or fines or seek disgorgement of revenue or profits;
• suspend any ongoing clinical trials;
• refuse to approve pending applications or supplements to approved applications filed by us or our collaborators;
• withdraw any regulatory approvals;
• impose restrictions on operations, including costly new manufacturing requirements, or shut down our manufacturing operations; or
• seize or detain products or require a product recall.

The FDA, the EMA and comparable foreign authorities strictly regulate the promotional claims that may be made about prescription products, such as our product candidates, if approved. In particular, a product may not be promoted for uses that are not approved by the FDA, the EMA or comparable foreign authorities as reflected in the product's approved labeling. If we receive marketing approval for our product candidates for our proposed indications, physicians may nevertheless use our products for their patients in a manner that is inconsistent with the approved label, if the physicians personally believe in their professional medical judgment that our products could be used in such manner. However, if we are found to have promoted our products for any off-label uses, the federal government could levy civil, criminal or administrative penalties, and seek fines against us. Such enforcement has become more common in the industry. The FDA, the EMA or comparable foreign authorities could also request that we enter into a consent decree or a corporate integrity agreement, or seek a permanent injunction against us under which specified promotional conduct is monitored, changed or curtailed. If we cannot successfully manage the

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promotion of our product candidates, if approved, we could become subject to significant liability, which would materially adversely affect our business, financial condition and results of operations.

The biopharmaceutical industry is characterized by rapidly advancing technologies, intense competition and a strong emphasis on proprietary products. While we believe that our technology, knowledge, experience and scientific resources provide us with competitive advantages, we face potential competition from many different sources, including commercial biopharmaceutical enterprises, academic institutions, government agencies and private and public research institutions. Any product candidates that we successfully develop and commercialize will compete with existing therapies and new therapies that may become available in the future.

Many of our competitors have significantly greater financial resources and expertise in research and development, manufacturing, preclinical studies, clinical trials, regulatory approvals and marketing approved products than we do. Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies. Our competitors may succeed in developing technologies and therapies that are more effective, better tolerated or less costly than any which we are developing, or that would render our product candidates obsolete and noncompetitive. Even if we obtain regulatory approval for any of our product candidates, our competitors may succeed in obtaining regulatory approvals for their products earlier than we do. We will also face competition from these third parties in recruiting and retaining qualified scientific and management personnel, in establishing clinical trial sites and patient registration for clinical trials, and in acquiring and in-licensing technologies and products complementary to our programs or advantageous to our business.

The key competitive factors affecting the success of each of our product candidates, if approved, are likely to be its efficacy, safety, tolerability, frequency and route of administration, convenience and price, the level of branded and generic competition and the availability of coverage and reimbursement from government and other third-party payors.

The pharmaceutical market for the treatment of major depressive disorder includes selective serotonin reuptake inhibitors ("SSRIs"), serotonin and norepinephrine reuptake inhibitors ("SNRIs") and atypical antipsychotics. A number of these marketed antidepressants will be generic, and would be key competitors to SLS-002. These products include Forest Laboratory's Lexapro/Cipralex (escitalopram) and Viibryd (vilazodone), Pfizer, Inc.'s Zoloft (sertraline), Effexor (venlafaxine) and Pristiq (desvenlafaxine), GlaxoSmithKline plc's Paxil/Seroxat (paroxetine), Eli Lilly and Company's Prozac (fluoxetine) and Cymbalta (duloxetine), AstraZeneca plc's Seroquel (quetiapine) and Bristol-Myers Squibb Company's Abilify (aripiprazole), among others.

Patients with treatment-resistant depression often require treatment with several antidepressants, such as an SSRI or SNRI, combined with an "adjunct" therapy such as an antipsychotic compound, such as AstraZeneca plc's Seroquel (quetiapine) and Bristol-Myers Squibb Company's Abilify (aripiprazole), or mood stabilizers, such as Janssen Pharmaceutica's Topamax (topiramate). In addition, Janssen's Spravato (intranasal esketamine), which has been approved for treatment-resistant depression and for depressive systems in adults with major depressive disorder with suicidal thoughts or actions, targets the NMDA receptor and is expected to have a faster onset of therapeutic effect as compared to currently available therapies.

Current treatments for Parkinson's Disease ("PD") are intended to improve the symptoms of patients. The cornerstone of PD therapy is levodopa, as it is the most effective therapy for reducing symptoms of PD. There are other drug therapies in development that will target the disease, such as gene and stem cell therapy and A2A receptor agonists.

Regulatory authorities in some jurisdictions, including the United States and Europe, may designate drugs for relatively small patient populations as orphan drugs. Under the Orphan Drug Act, the FDA may designate a product as an orphan drug if it is a drug intended to treat a rare disease or condition, which is generally defined as a patient population of fewer than 200,000 individuals annually in the United States. In the United States and Europe, obtaining orphan drug approval may allow us to obtain financial incentives, such as an extended period of exclusivity during which only we are allowed to market the orphan drug. While we plan to seek orphan drug designation from the FDA for SLS-008 for the treatment of a pediatric indication, we, or any future collaborators, may not be granted orphan drug designations for our product candidates in the U.S. or in other jurisdictions.

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Even if we, or any future collaborators, obtain orphan drug designation for a product candidate, we, or they, may not be able to obtain orphan drug exclusivity for that product candidate. Generally, a product with orphan drug designation only becomes entitled to orphan drug exclusivity if it receives the first marketing approval for the indication for which it has such designation, in which case the FDA or the EMA will be precluded from approving another marketing application for the same drug for that indication for the applicable exclusivity period. The applicable exclusivity period is seven years in the United States and ten years in Europe. The European exclusivity period can be reduced to six years if a drug no longer meets the criteria for orphan drug designation or if the drug is sufficiently profitable so that market exclusivity is no longer justified. Orphan drug exclusivity may be lost if the FDA or the EMA determines that the request for designation was materially defective or if the manufacturer is unable to assure sufficient quantity of the drug to meet the needs of patients with the rare disease or condition.

Even if we, or any future collaborators, obtain orphan drug exclusivity for a product, that exclusivity may not effectively protect the product from competition because FDA has taken the position that, under certain circumstances, another drug with the same active chemical and pharmacological characteristics, or moiety, can be approved for the same condition. Specifically, the FDA's regulations provide that it can approve another drug with the same active moiety for the same condition if the FDA concludes that the later drug is clinically superior in that it is shown to be safer, more effective or makes a major contribution to patient care.

Ketamine is listed by the Drug Enforcement Administration ("DEA") as a Schedule III controlled substance under the Controlled Substances Act. The DEA classifies substances as Schedule I, II, III, IV or V controlled substances, with Schedule I controlled substances considered to present the highest risk of substance abuse and Schedule V controlled substances the lowest risk. Scheduled controlled substances are subject to DEA regulations relating to supply, procurement, manufacturing, storage, distribution and physician prescription procedures. In addition to federal scheduling, some drugs may be subject to state-level controlled substance laws and regulations and in some cases more broadly applicable or more extensive requirements than those determined by the DEA and FDA. Federal and state-level controlled substance laws impose a broad range of registration and licensure requirements along with requirements for systems and controls intended to provide security and reduce the risk of diversion and misuse, and to identify suspicious activities.

Compliance with these laws can be expensive and time consuming. Failure to follow these requirements can lead to significant civil and/or criminal penalties and possibly even lead to a revocation of a DEA registration and state-level licenses.

If SLS-002 receives marketing approval from the FDA or other regulatory authority, we may be required to implement REMS to address the potential for abuse and misuse of our product candidate. As a result, our product candidate may only be available through a restricted or limited distribution system to which only certain prescribing healthcare professionals may have access for their patients or healthcare professionals may be limited in their prescribing.

Furthermore, product candidates containing controlled substances may generate public controversy. As a result, these products may be at risk of having their sale and distribution and marketing approvals further restricted or in extreme cases withdrawn in the event that regulators were to assess that the benefits of a product no longer outweigh emerging risks. Political pressures or adverse publicity could lead to delays in, and increased expenses for, and limit or restrict, the commercialization of our product or product candidates.

The process of manufacturing our product candidates is complex, highly regulated, and subject to several risks. For example, the process of manufacturing our product candidates is extremely susceptible to product loss due to contamination, equipment failure or improper installation or operation of equipment, or vendor or operator error. Even minor deviations from normal manufacturing processes for any of our product candidates could result in reduced production yields, product defects and other supply disruptions. If microbial, viral or other contaminations are discovered in our product candidates or in the manufacturing facilities in which our product candidates are made, such manufacturing facilities may need to be closed for an extended period of time to investigate and remedy the contamination. In addition, the manufacturing facilities in which our product candidates are made could be adversely affected by equipment failures, labor shortages, natural disasters, public health crises, pandemics and epidemics, such as the recent coronavirus disease 2019 (COVID-19), power failures and numerous other factors.

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In addition, any adverse developments affecting manufacturing operations for our product candidates may result in shipment delays, inventory shortages, lot failures, withdrawals or recalls or other interruptions in the supply of our product candidates. We also may need to take inventory write-offs and incur other charges and expenses for product candidates that fail to meet specifications, undertake costly remediation efforts or seek costlier manufacturing alternatives.

We do not currently have, nor do we plan to acquire, the infrastructure or capability internally to manufacture our preclinical and clinical drug supplies for use in our clinical trials, and we lack the resources and the capability to manufacture any of our product candidates on a clinical or commercial scale. We rely on our manufacturers to purchase from third-party suppliers the materials necessary to produce our product candidates for our clinical trials. There are a limited number of suppliers for raw materials that we use to manufacture our product candidates, and there may be a need to identify alternate suppliers to prevent a possible disruption of the manufacture of the materials necessary to produce our product candidates for our clinical trials, and, if approved, ultimately for commercial sale. We do not have any control over the process or timing of the acquisition of these raw materials by our manufacturers. Although we generally do not begin a clinical trial unless we believe we have a sufficient supply of a product candidate to complete such clinical trial, any significant delay or discontinuity in the supply of a product candidate, or the raw material components thereof, for an ongoing clinical trial due to the need to replace a third-party manufacturer could considerably delay completion of our clinical trials, product testing and potential regulatory approval of our product candidates, which could harm our business, financial condition and results of operations.

SLS-002 is delivered by an intranasal delivery device and considered a drug-device combination product (the device having been developed by a third party is subject to a pending license agreement). When evaluating products that utilize a specific drug delivery system or device, the FDA will evaluate the characteristics of that delivery system and its functionality, as well as the potential for undesirable interactions between the drug and the delivery system, including the potential to negatively impact the safety or effectiveness of the drug. The FDA review process can be more complicated for combination products, and may result in delays, particularly if novel delivery systems are involved. Additionally, quality or design concerns with the delivery system could delay or prevent regulatory approval and commercialization of our product candidates.

All entities involved in the preparation of therapeutics for clinical trials or commercial sale, including our contract manufacturers for our product candidates, are subject to extensive regulation. Components of a finished therapeutic product approved for commercial sale or used in late-stage clinical trials must be manufactured in accordance with cGMP. These regulations govern manufacturing processes and procedures and the implementation and operation of quality systems to control and assure the quality of investigational products and products approved for sale. Poor control of production processes can lead to the introduction of contaminants or to inadvertent changes in the properties or stability of our product candidates that may not be detectable in final product testing. We or our contract manufacturers must supply all necessary documentation in support of an NDA or marketing authorization application ("MAA") on a timely basis and must adhere to GLP and cGMP regulations enforced by the FDA, the EMA or comparable foreign authorities through their facilities inspection program. Some of our contract manufacturers may not have produced a commercially approved pharmaceutical product and therefore may not have obtained the requisite regulatory authority approvals to do so. The facilities and quality systems of some or all of our third-party contractors must pass a pre-approval inspection for compliance with the applicable regulations as a condition of regulatory approval of our product candidates or any of our other potential products. In addition, the regulatory authorities may, at any time, audit or inspect a manufacturing facility involved with the preparation of our product candidates or any of our other potential products or the associated quality systems for compliance with the regulations applicable to the activities being conducted. Although we plan to oversee the contract manufacturers, we cannot control the manufacturing process of, and are completely dependent on, our contract manufacturing partners for compliance with the regulatory requirements. If these facilities do not pass a pre-approval plant inspection, regulatory approval of the products may not be granted or may be substantially delayed until any violations are corrected to the satisfaction of the regulatory authority, if ever.

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The regulatory authorities also may, at any time following approval of a product for sale, audit the manufacturing facilities of our third-party contractors. If any such inspection or audit identifies a failure to comply with applicable regulations or if a violation of our product specifications or applicable regulations occurs independent of such an inspection or audit, we or the relevant regulatory authority may require remedial measures that may be costly or time consuming for us or a third party to implement, and that may include the temporary or permanent suspension of a clinical trial or commercial sales or the temporary or permanent closure of a facility. Any such remedial measures imposed upon us or third parties with whom we contract could materially harm our business, financial condition and results of operations.

If we or any of our third-party manufacturers fail to maintain regulatory compliance, the FDA, the EMA or comparable foreign authorities can impose regulatory sanctions including, among other things, refusal to approve a pending application for a product candidate, withdrawal of an approval or suspension of production. As a result, our business, financial condition and results of operations may be materially and adversely affected.

Additionally, if supply from one manufacturer is interrupted, an alternative manufacturer would need to be qualified through an NDA supplement or MAA variation, or equivalent foreign regulatory filing, which could result in further delay. The regulatory agencies may also require additional studies or trials if a new manufacturer is relied upon for commercial production. Switching manufacturers may involve substantial costs and is likely to result in a delay in our desired clinical and commercial timelines.

These factors could cause us to incur higher costs and could cause the delay or termination of clinical trials, regulatory submissions, required approvals, or commercialization of our product candidates. Furthermore, if our suppliers fail to meet contractual requirements and we are unable to secure one or more replacement suppliers capable of production at a substantially equivalent cost, our clinical trials may be delayed or we could lose potential revenue.

We may seek collaboration arrangements with biopharmaceutical companies for the development or commercialization of our current and potential future product candidates. To the extent that we decide to enter into collaboration agreements, we will face significant competition in seeking appropriate collaborators. Moreover, collaboration arrangements are complex and time consuming to negotiate, execute and implement. We may not be successful in our efforts to establish and implement collaborations or other alternative arrangements should we choose to enter into such arrangements, and the terms of the arrangements may not be favorable to us. If and when we collaborate with a third party for development and commercialization of a product candidate, we can expect to relinquish some or all of the control over the future success of that product candidate to the third party. The success of our collaboration arrangements will depend heavily on the efforts and activities of our collaborators. Collaborators generally have significant discretion in determining the efforts and resources that they will apply to these collaborations.

Disagreements between parties to a collaboration arrangement can lead to delays in developing or commercializing the applicable product candidate and can be difficult to resolve in a mutually beneficial manner. In some cases, collaborations with biopharmaceutical companies and other third parties are terminated or allowed to expire by the other party. Any such termination or expiration would adversely affect our business, financial condition and results of operations.

We do not have a sales and marketing organization, and we have no experience as a company in the sales, marketing and distribution of pharmaceutical products. If any of our product candidates are approved for commercialization, we may be required to develop our sales, marketing and distribution capabilities, or make arrangements with a third party to perform sales and marketing services. Developing a sales force for any resulting product or any product resulting from any of our other product candidates is expensive and time consuming and could delay any product launch. We may be unable to establish and manage an effective sales force in a timely or cost-effective manner, if at all, and any sales force we do establish may not be capable of generating sufficient demand for our product candidates. To the extent that we enter into arrangements with collaborators or other third parties to perform sales and marketing services, our product revenues are likely to be lower than if we marketed and sold our product candidates independently. If we are unable to establish adequate sales and marketing capabilities, independently or with others, we may not be able to generate significant revenues and may not become profitable.

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The commercial success of our product candidates depends upon their market acceptance among physicians, patients, healthcare payors and the medical community.

Even if our product candidates obtain regulatory approval, our products, if any, may not gain market acceptance among physicians, patients, healthcare payors and the medical community. The degree of market acceptance of any of our approved product candidates will depend on a number of factors, including:

• the effectiveness of our approved product candidates as compared to currently available products;
• patient willingness to adopt our approved product candidates in place of current therapies;
• our ability to provide acceptable evidence of safety and efficacy;
• relative convenience and ease of administration;
• the prevalence and severity of any adverse side effects;
• restrictions on use in combination with other products;
• availability of alternative treatments;
• pricing and cost-effectiveness assuming either competitive or potential premium pricing requirements, based on the profile of our product candidates and target markets;
• effectiveness of us or our partners' sales and marketing strategy;
• our ability to obtain sufficient third-party coverage or reimbursement; and
• potential product liability claims.

In addition, the potential market opportunity for our product candidates is difficult to precisely estimate. Our estimates of the potential market opportunity for our product candidates include several key assumptions based on our industry knowledge, industry publications, third-party research reports and other surveys. Independent sources have not verified all of our assumptions. If any of these assumptions proves to be inaccurate, then the actual market for our product candidates could be smaller than our estimates of the potential market opportunity. If the actual market for our product candidates is smaller than we expect, our product revenue may be limited, it may be harder than expected to raise funds and it may be more difficult for us to achieve or maintain profitability. If we fail to achieve market acceptance of our product candidates in the U.S. and abroad, our revenue will be limited and it will be more difficult to achieve profitability.

There will be no viable commercial market for our product candidates, if approved, without reimbursement from third-party payors. Reimbursement policies may be affected by future healthcare reform measures. We cannot be certain that reimbursement will be available for our current product candidates or any other product candidate we may develop. Additionally, even if there is a viable commercial market, if the level of reimbursement is below our expectations, our anticipated revenue and gross margins will be adversely affected.

Third-party payors, such as government or private healthcare insurers, carefully review and increasingly question and challenge the coverage of and the prices charged for drugs. Reimbursement rates from private health insurance companies vary depending on the company, the insurance plan and other factors. Reimbursement rates may be based on reimbursement levels already set for lower cost drugs and may be incorporated into existing payments for other services. There is a current trend in the U.S. healthcare industry toward cost containment.

Large public and private payors, managed care organizations, group purchasing organizations and similar organizations are exerting increasing influence on decisions regarding the use of, and reimbursement levels for, particular treatments. Such third-party payors, including Medicare, may question the coverage of, and challenge the prices charged for, medical products and services, and many third-party payors limit coverage of or reimbursement for newly approved healthcare products. In particular, third-party payors may limit the covered indications. Cost-control initiatives could decrease the price we might establish for products, which could result in product revenues being lower than anticipated. We believe our drugs will be priced significantly higher than existing generic drugs and consistent with current branded drugs. If we are unable to show a significant benefit relative to existing generic drugs, Medicare, Medicaid and private payors may not be willing to provide reimbursement for our drugs, which would significantly reduce the likelihood of our products gaining market acceptance.

We expect that private insurers will consider the efficacy, cost-effectiveness, safety and tolerability of our potential products in determining whether to approve reimbursement for such products and at what level. Obtaining these approvals can be a time consuming and expensive process. Our business, financial condition and results of operations would be materially adversely affected if we do not receive approval for reimbursement of our potential products from private insurers on a timely or satisfactory basis. Limitations on coverage could also be imposed at the local Medicare carrier level or by fiscal intermediaries. Medicare Part D, which provides a pharmacy benefit to Medicare patients as discussed below, does not require

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participating prescription drug plans to cover all drugs within a class of products. Our business, financial condition and results of operations could be materially adversely affected if Part D prescription drug plans were to limit access to, or deny or limit reimbursement of, our product candidates or other potential products.

Reimbursement systems in international markets vary significantly by country and by region, and reimbursement approvals must be obtained on a country-by-country basis. In many countries, the product cannot be commercially launched until reimbursement is approved. In some foreign markets, prescription pharmaceutical pricing remains subject to continuing governmental control even after initial approval is granted. The negotiation process in some countries can exceed 12 months. To obtain reimbursement or pricing approval in some countries, we may be required to conduct a clinical trial that compares the cost-effectiveness of our products to other available therapies.

If the prices for our potential products are reduced or if governmental and other third-party payors do not provide adequate coverage and reimbursement of our drugs, our future revenue, cash flows and prospects for profitability will suffer.

In the U.S. and some foreign jurisdictions, there have been a number of adopted and proposed legislative and regulatory changes regarding the healthcare system that could prevent or delay regulatory approval of our product candidates, restrict or regulate post-marketing activities and affect our ability to profitably sell any of our product candidates for which we obtain regulatory approval.

In the U.S., the Medicare Prescription Drug, Improvement, and Modernization Act of 2003 ("MMA") changed the way Medicare covers and pays for pharmaceutical products. Cost reduction initiatives and other provisions of this legislation could limit the coverage and reimbursement rate that we receive for any of our approved products. While the MMA only applies to drug benefits for Medicare beneficiaries, private payors often follow Medicare coverage policy and payment limitations in setting their own reimbursement rates. Therefore, any reduction in reimbursement that results from the MMA may result in a similar reduction in payments from private payors.

In March 2010, the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act of 2010 (collectively the "PPACA"), was enacted. The PPACA was intended to broaden access to health insurance, reduce or constrain the growth of healthcare spending, enhance remedies against healthcare fraud and abuse, add new transparency requirements for healthcare and health insurance industries, impose new taxes and fees on the health industry and impose additional health policy reforms. The PPACA increased manufacturers' rebate liability under the Medicaid Drug Rebate Program by increasing the minimum rebate amount for both branded and generic drugs and revised the definition of "average manufacturer price", which may also increase the amount of Medicaid drug rebates manufacturers are required to pay to states. The legislation also expanded Medicaid drug rebates and created an alternative rebate formula for certain new formulations of certain existing products that is intended to increase the rebates due on those drugs. The Centers for Medicare & Medicaid Services, which administers the Medicaid Drug Rebate Program, also has proposed to expand Medicaid rebates to the utilization that occurs in the territories of the U.S., such as Puerto Rico and the Virgin Islands. Further, beginning in 2011, the PPACA imposed a significant annual fee on companies that manufacture or import branded prescription drug products and required manufacturers to provide a 50% discount off the negotiated price of prescriptions filled by beneficiaries in the Medicare Part D coverage gap, referred to as the "donut hole." Legislative and regulatory proposals have been introduced at both the state and federal level to expand post-approval requirements and restrict sales and promotional activities for pharmaceutical products.

There have been public announcements by members of the U.S. Congress regarding plans to repeal and replace the PPACA and Medicare. For example, on December 22, 2017 the Tax Cuts and Jobs Act of 2017 was signed into law, which, among other things, eliminated the individual mandate requiring most Americans (other than those who qualify for a hardship exemption) to carry a minimum level of health coverage, effective January 1, 2019. We are not sure whether additional legislative changes will be enacted, or whether the FDA regulations, guidance or interpretations will be changed, or what the impact of such changes on the marketing approvals of our product candidates, if any, may be. In addition, increased scrutiny by the U.S. Congress of the FDA's approval process may significantly delay or prevent marketing approval, as well as subject us to more stringent product labeling and post-marketing approval testing and other requirements.

In addition to the PPACA, there will continue to be proposals by legislators at both the federal and state levels, regulators and third-party payers to reduce costs while expanding individual healthcare benefits. Certain of these changes could impose additional limitations on the prices we will be able to charge for our current and future solutions or the amounts of reimbursement available for our current and future solutions from governmental agencies or third-party payers. While in general it is difficult to predict specifically what effects the PPACA or any future healthcare reform legislation or policies will

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have on our business, current and future healthcare reform legislation and policies could have a material adverse effect on our business and financial condition.

In Europe, the United Kingdom withdrew from the European Union on January 31, 2020 and began a transition period that ended on December 31, 2020. Although the effects of Brexit have yet to be seen, and the UK is in the process of negotiating trade deals with other countries, Brexit has created additional uncertainties that may ultimately result in new regulatory costs and challenges for companies and increased restrictions on imports and exports throughout Europe, which could adversely affect our ability to conduct and expand our operations in Europe and which may have an adverse effect on our business, financial condition and results of operations. Additionally, Brexit may increase the possibility that other countries may decide to leave the EU in the future.

The ability of the FDA to review and approve new products can be affected by a variety of factors, including budget and funding levels, ability to hire and retain key personnel, and statutory, regulatory and policy changes. Average review times at the agency have fluctuated in recent years as a result. In addition, government funding of other agencies that fund research and development activities is subject to the political process, which is inherently fluid and unpredictable.

In December 2016, the 21^st Century Cures Act was signed into law. This new legislation is designed to advance medical innovation and empower the FDA with the authority to directly hire positions related to drug and device development and review. However, government proposals to reduce or eliminate budgetary deficits may include reduced allocations to the FDA and other related government agencies. These budgetary pressures may result in a reduced ability by the FDA to perform their respective roles; including the related impact to academic institutions and research laboratories whose funding is fully or partially dependent on both the level and timing of funding from government sources.

Disruptions at the FDA and other agencies may also slow the time necessary for our product candidates to be reviewed or approved by necessary government agencies, which could adversely affect our business, financial condition and results of operations.

In the U.S., we are subject to various federal and state healthcare "fraud and abuse" laws, including anti-kickback laws, false claims laws and other laws intended, among other things, to reduce fraud and abuse in federal and state healthcare programs. The federal Anti-Kickback Statute makes it illegal for any person, including a prescription drug manufacturer, or a party acting on its behalf, to knowingly and willfully solicit, receive, offer or pay any remuneration that is intended to induce the referral of business, including the purchase, order or prescription of a particular drug, or other good or service for which payment in whole or in part may be made under a federal healthcare program, such as Medicare or Medicaid. Although we seek to structure our business arrangements in compliance with all applicable requirements, these laws are broadly written, and it is often difficult to determine precisely how the law will be applied in specific circumstances. Accordingly, it is possible that our practices may be challenged under the federal Anti-Kickback Statute.

The federal False Claims Act prohibits anyone from, among other things, knowingly presenting or causing to be presented for payment to the government, including the federal healthcare programs, claims for reimbursed drugs or services that are false or fraudulent, claims for items or services that were not provided as claimed, or claims for medically unnecessary items or services. Under the Health Insurance Portability and Accountability Act of 1996, we are prohibited from knowingly and willfully executing a scheme to defraud any healthcare benefit program, including private payors, or knowingly and willfully falsifying, concealing or covering up a material fact or making any materially false, fictitious or fraudulent statement in connection with the delivery of or payment for healthcare benefits, items or services to obtain money or property of any healthcare benefit program. Violations of fraud and abuse laws may be punishable by criminal or civil sanctions, including penalties, fines or exclusion or suspension from federal and state healthcare programs such as Medicare and Medicaid and debarment from contracting with the U.S. government. In addition, private individuals have the ability to bring actions on behalf of the government under the federal False Claims Act as well as under the false claims laws of several states.

Many states have adopted laws similar to the federal Anti-Kickback Statute, some of which apply to the referral of patients for healthcare services reimbursed by any source, not just governmental payors. In addition, some states have passed laws that require pharmaceutical companies to comply with the April 2003 Office of Inspector General Compliance Program Guidance for Pharmaceutical Manufacturers or the Pharmaceutical Research and Manufacturers of America's Code on Interactions with Healthcare Professionals. Several states also impose other marketing restrictions or require pharmaceutical companies to make

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marketing or price disclosures to the state. There are ambiguities as to what is required to comply with these state requirements and if we fail to comply with an applicable state law requirement, we could be subject to penalties.

Neither the government nor the courts have provided definitive guidance on the application of fraud and abuse laws to our business. Law enforcement authorities are increasingly focused on enforcing these laws, and it is possible that some of our practices may be challenged under these laws. Efforts to ensure that our business arrangements with third parties will comply with applicable healthcare laws and regulations will involve substantial costs. If we are found in violation of one of these laws, we could be subject to significant civil, criminal and administrative penalties, damages, fines, exclusion from governmental funded federal or state healthcare programs and the curtailment or restructuring of our operations. If this occurs, our business, financial condition and results of operations may be materially adversely affected.

Any government investigation of alleged violations of law could require us to expend significant time and resources in response, and could generate negative publicity. Any failure to comply with ongoing regulatory requirements may significantly and adversely affect our ability to generate revenues from any of our product candidates that are ultimately approved for commercialization. If regulatory sanctions are applied or if regulatory approval is withdrawn, our business, financial condition and results of operations will be adversely affected. Additionally, if we are unable to generate revenues from product sales, our potential for achieving profitability will be diminished and our need to raise capital to fund our operations will increase.

Our success depends on our continued ability to attract, retain and motivate highly qualified management and scientific personnel. As of March 4, 2021, we have 11 employees. Our organization will rely primarily on outsourcing research, development and clinical trial activities, and manufacturing operations, as well as other functions critical to our business. We believe this approach enhances our ability to focus on our core product opportunities, allocate resources efficiently to different projects and allocate internal resources more effectively. We have filled several key open positions and are currently recruiting for a few remaining positions. However, competition for qualified personnel is intense. We may not be successful in attracting qualified personnel to fulfill our current or future needs and there is no guarantee that any of these individuals will join us on a full-time employment basis, or at all. In the event we are unable to fill critical open employment positions, we may need to delay our operational activities and goals, including the development of our product candidates, and may have difficulty in meeting our obligations as a public company. We do not maintain "key person" insurance on any of our employees.

In addition, competitors and others are likely in the future to attempt to recruit our employees. The loss of the services of any of our key personnel, the inability to attract or retain highly qualified personnel in the future or delays in hiring such personnel, particularly senior management and other technical personnel, could materially and adversely affect our business, financial condition and results of operations. In addition, the replacement of key personnel likely would involve significant time and costs, and may significantly delay or prevent the achievement of our business objectives.

From time to time, our management seeks the advice and guidance of certain scientific advisors and consultants regarding clinical and regulatory development programs and other customary matters. These scientific advisors and consultants are not our employees and may have commitments to, or consulting or advisory contracts with, other entities that may limit their availability to us. In addition, our scientific advisors may have arrangements with other companies to assist those companies in developing products or technologies that may compete with us.

We are a clinical-stage biopharmaceutical company with a small number of planned employees, and our management system currently in place is not likely to be adequate to support our future growth plans. Our ability to grow and to manage our growth effectively will require us to hire, train, retain, manage and motivate additional employees and to implement and improve our operational, financial and management systems. These demands also may require the hiring of additional senior management personnel or the development of additional expertise by our senior management personnel. Hiring a significant number of additional employees, particularly those at the management level, would increase our expenses significantly. Moreover, if we fail to expand and enhance our operational, financial and management systems in conjunction with our potential future growth, it could have a material adverse effect on our business, financial condition and results of operations.

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Our management's lack of public company experience could put us at greater risk of incurring fines or regulatory actions for failure to comply with federal securities laws and could put us at a competitive disadvantage, and could require our management to devote additional time and resources to ensure compliance with applicable corporate governance requirements.

Our executive officer does not have prior experience in managing and operating a public company, which could have an adverse effect on his ability to quickly respond to problems or adequately address issues and matters applicable to public companies. Any failure to comply with federal securities laws, rules or regulations could subject us to fines or regulatory actions, which may materially adversely affect our business, financial condition and results of operations. Further, since our executive officer does not have prior experience managing and operating a public company, we may need to dedicate additional time and resources to comply with legally mandated corporate governance policies relative to our competitors whose management teams have more public company experience.

Our business exposes us to potential product liability and other liability risks that are inherent in the testing, manufacturing and marketing of pharmaceutical formulations and products. In addition, the use in our clinical trials of pharmaceutical products and the subsequent sale of these products by us or our potential collaborators may cause us to bear a portion of or all product liability risks. A successful liability claim or series of claims brought against us could have a material adverse effect on our business, financial condition and results of operations.

We currently carry product liability insurance for our clinical development activities. On occasion, large judgments have been awarded in class action lawsuits based on drugs that had unanticipated adverse effects. A successful product liability claim or series of claims brought against us could cause our stock price to decline and, if judgments exceed our insurance coverage, could adversely affect our results of operations and business.

Our research and development activities involve the controlled use of hazardous materials and chemicals, and we will need to develop additional safety procedures for the handling and disposing of hazardous materials. If an accident occurs, we could be held liable for resulting damages, which could be substantial. We are also subject to numerous environmental, health and workplace safety laws and regulations, including those governing laboratory procedures, exposure to blood-borne pathogens and the handling of biohazardous materials. Additional federal, state and local laws and regulations affecting our operations may be adopted in the future. We may incur substantial costs to comply with, and substantial fines or penalties if we violate any of these laws or regulations.

Despite the implementation of security measures, our internal computer systems and those of third parties with which we contract are vulnerable to damage from cyber-attacks, computer viruses, unauthorized access, natural disasters, terrorism, war and telecommunication and electrical failures. System failures, accidents or security breaches could cause interruptions in our operations, and could result in a material disruption of our drug development and clinical activities and business operations, in addition to possibly requiring substantial expenditures of resources to remedy. The loss of drug development or clinical trial data could result in delays in our regulatory approval efforts and significantly increase our costs to recover or reproduce the data. To the extent that any disruption or security breach were to result in a loss of, or damage to, our data or applications, or inappropriate disclosure of confidential or proprietary information, we could incur liability and our development programs and the development of our product candidates could be delayed.

We are exposed to the risk of employee or consultant fraud or other misconduct. Misconduct by our employees or consultants could include intentional failures to comply with FDA regulations, provide accurate information to the FDA, comply with manufacturing standards, comply with federal and state healthcare fraud and abuse laws and regulations, report financial information or data accurately or disclose unauthorized activities to us. In particular, sales, marketing and business arrangements in the healthcare industry are subject to extensive laws and regulations intended to prevent fraud, kickbacks, self-dealing and other abusive practices. These laws and regulations may restrict or prohibit a wide range of pricing, discounting, marketing and promotion, sales commissions, customer incentive programs and other business arrangements. Employee and

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consultant misconduct also could involve the improper use of information obtained in the course of clinical trials, which could result in regulatory sanctions and serious harm to our reputation. It is not always possible to identify and deter such misconduct, and the precautions we take to detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses or in protecting us from governmental investigations or other actions or lawsuits stemming from a failure to be in compliance with such laws or regulations. If any such actions are instituted against us, and we are not successful in defending ourselves or asserting our rights, those actions could have a material adverse effect on our business, financial condition and results of operations, and result in the imposition of significant fines or other sanctions against us.

We and our suppliers may experience a disruption in our and their business as a result of natural disasters. A significant natural disaster, such as an earthquake, hurricane, flood or fire, could severely damage or destroy our headquarters or facilities or the facilities of our manufacturers or suppliers, which could have a material and adverse effect on our business, financial condition and results of operations. In addition, terrorist acts or acts of war targeted at the U.S., and specifically the greater New York, New York region, could cause damage or disruption to us, our employees, facilities, partners and suppliers, which could have a material adverse effect on our business, financial condition and results of operations.

From time to time, we may consider strategic transactions, such as acquisitions of companies, asset purchases and out-licensing or in-licensing of products, product candidates or technologies. Additional potential transactions that we may consider include a variety of different business arrangements, including spin-offs, strategic partnerships, joint ventures, restructurings, divestitures, business combinations and investments. Any such transaction may require us to incur non-recurring or other charges, may increase our near- and long-term expenditures and may pose significant integration challenges or disrupt our management or business, which could adversely affect our business, financial condition and results of operations. For example, these transactions may entail numerous operational and financial risks, including:

• exposure to unknown liabilities;
• disruption of our business and diversion of our management's time and attention in order to develop acquired products, product candidates or technologies;
• incurrence of substantial debt or dilutive issuances of equity securities to pay for any of these transactions;
• higher-than-expected transaction and integration costs;
• write-downs of assets or goodwill or impairment charges;
• increased amortization expenses;
• difficulty and cost in combining the operations and personnel of any acquired businesses or product lines with our operations and personnel;
• impairment of relationships with key suppliers or customers of any acquired businesses or product lines due to changes in management and ownership; and
• inability to retain key employees of any acquired businesses.

Accordingly, although there can be no assurance that we will undertake or successfully complete any transactions of the nature described above, any transactions that we do complete may be subject to the foregoing or other risks, and could have a material adverse effect on our business, financial condition and results of operations.

Because several of our programs require the use of proprietary rights held by third parties, the growth of our business will likely depend in part on our ability to maintain and exploit these proprietary rights. In addition, we may need to acquire or in-license additional intellectual property in the future. We may be unable to acquire or in-license any compositions, methods of use, processes or other intellectual property rights from third parties that we identify as necessary for our product candidates. We face competition with regard to acquiring and in-licensing third-party intellectual property rights, including from a number of more established companies. These established companies may have a competitive advantage over us due to their size, cash resources and greater clinical development and commercialization capabilities. In addition, companies that perceive us to be a competitor may be unwilling to assign or license intellectual property rights to us. We also may be unable to acquire or in-license third-party intellectual property rights on terms that would allow us to make an appropriate return on our investment.

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We may enter into collaboration agreements with U.S. and foreign academic institutions to accelerate development of our current or future preclinical product candidates. Typically, these agreements include an option for the company to negotiate a license to the institution's intellectual property rights resulting from the collaboration. Even with such an option, we may be unable to negotiate a license within the specified timeframe or under terms that are acceptable to us. If we are unable to license rights from a collaborating institution, the institution may offer the intellectual property rights to other parties, potentially blocking our ability to pursue our desired program.

If we are unable to successfully obtain required third-party intellectual property rights or maintain our existing intellectual property rights, we may need to abandon development of the related program and our business, financial condition and results of operations could be materially and adversely affected.

Our license agreement with Ligand Pharmaceuticals Incorporated, Neurogen Corporation and CyDex Pharmaceuticals, Inc. (the "Ligand License Agreement"), our license agreement with the Regents of the University of California (the "UC Regents License Agreement") and our license agreement with Duke University (the "Duke License Agreement", together with the Ligand License Agreement and the UC Regents License Agreement, the "License Agreements") are important to our business and we expect to enter into additional license agreements in the future. The License Agreements impose, and we expect that future license agreements will impose, various milestone payments, royalties and other obligations on us. If we fail to comply with our obligations under these agreements, or if we file for bankruptcy, we may be required to make certain payments to the licensor, we may lose the exclusivity of our license, or the licensor may have the right to terminate the license, in which event we would not be able to develop or market products covered by the license. Additionally, the milestone and other payments associated with these licenses could materially and adversely affect our business, financial condition and results of operations.

Pursuant to the terms of the Ligand License Agreement, the licensors each have the right to terminate the Ligand License Agreement with respect to the programs licensed by such licensor under certain circumstances, including, but not limited to: (i) if we do not pay an amount that is not disputed in good faith, (ii) if we willfully breach the Ligand License Agreement in a manner for which legal remedies would not be expected to make such licensor whole, or (iii) if we file or have filed against us a petition in bankruptcy or make an assignment for the benefit of creditors. In the event the Ligand License Agreement is terminated by a licensor, all licenses granted to us by such licensor will terminate immediately. Further, pursuant to the terms of the UC Regents License Agreement, the licensor has the right to terminate the UC Regents License Agreement or reduce our license to a nonexclusive license if we fail to achieve certain milestones within a specified timeframe. Similarly, pursuant to the terms of the Duke License Agreement, the licensor has the right to terminate the Duke License Agreement if we fail to achieve certain milestones within a specified timeframe.

In some cases, patent prosecution of our licensed technology may be controlled solely by the licensor. If our licensor fails to obtain and maintain patent or other protection for the proprietary intellectual property we in-license, then we could lose our rights to the intellectual property or our exclusivity with respect to those rights, and our competitors could market competing products using the intellectual property. In certain cases, we may control the prosecution of patents resulting from licensed technology. In the event we breach any of our obligations related to such prosecution, we may incur significant liability to our licensing partners. Licensing of intellectual property is of critical importance to our business and involves complex legal, business and scientific issues. Disputes may arise regarding intellectual property subject to a licensing agreement, including, but not limited to:

• the scope of rights granted under the license agreement and other interpretation-related issues;
• the extent to which our technology and processes infringe on intellectual property of the licensor that is not subject to the licensing agreement;
• the sublicensing of patent and other rights;
• our diligence obligations under the license agreement and what activities satisfy those diligence obligations;
• the ownership of inventions and know-how resulting from the joint creation or use of intellectual property by us, our licensors and our collaborators; and
• the priority of invention of patented technology.

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If disputes over intellectual property and other rights that we have in-licensed prevents or impairs our ability to maintain our current licensing arrangements on acceptable terms, we may be unable to successfully develop and commercialize the affected product candidates. If we fail to comply with any such obligations to our licensor, such licensor may terminate their licenses to us, in which case we would not be able to market products covered by these licenses. The loss of our licenses would have a material adverse effect on our business.

Under the terms of the Ligand License Agreement, we may be obligated to pay the licensors under the License Agreement up to an aggregate of approximately $135 million in development, regulatory and sales milestones. We will also be required to pay royalties on future worldwide net product sales. In addition pursuant to the asset purchase agreement, as amended, with Vyera Pharmaceuticals AG ("Vyera") we may be obligated to pay an aggregate of approximately $92.5 million in development, regulatory and sales milestones and we will be required to pay royalties to Vyera on any net sales of SLS-002. We will also be required to pay up to an aggregate of approximately $17 million in development and regulatory milestones and royalties on any net sales of SLS-005 pursuant to our asset purchase agreement with Bioblast Pharma Ltd. These cash, milestone and royalty payments could adversely affect the overall profitability for us of any products that we may seek to commercialize. Pursuant to the amended and restated license agreement with Stuart Weg, M.D., we will be required to make a $0.2 million cash payment to Dr. Weg in January 2022 if certain conditions are not met.

We depend on our ability to protect our proprietary or licensed technology. We rely on trade secret, patent, copyright and trademark laws, and confidentiality, licensing and other agreements with employees and third parties, all of which offer only limited protection. Our success depends in large part on our ability and any licensor's or licensee's ability to obtain and maintain patent protection in the U.S. and other countries with respect to our proprietary or licensed technology and products. We currently in-license some of our intellectual property rights to develop our product candidates and may in-license additional intellectual property rights in the future. We cannot be certain that patent enforcement activities by our current or future licensors have been or will be conducted in compliance with applicable laws and regulations or will result in valid and enforceable patents or other intellectual property rights. We also cannot be certain that our current or future licensors will allocate sufficient resources or prioritize their or our enforcement of such patents. Even if we are not a party to these legal actions, an adverse outcome could prevent us from continuing to license intellectual property that we may need to operate our business, which would have a material adverse effect on our business, financial condition and results of operations.

We believe we will be able to obtain, through prosecution of patent applications covering our owned technology and technology licensed from others, adequate patent protection for our proprietary drug technology, including those related to our in-licensed intellectual property. If we are compelled to spend significant time and money protecting or enforcing our licensed patents and future patents we may own, designing around patents held by others or licensing or acquiring, potentially for large fees, patents or other proprietary rights held by others, our business, financial condition and results of operations may be materially and adversely affected. If we are unable to effectively protect the intellectual property that we own or in-license, other companies may be able to offer the same or similar products for sale, which could materially adversely affect our business, financial condition and results of operations. The patents of others from whom we may license technology, and any future patents we may own, may be challenged, narrowed, invalidated or circumvented, which could limit our ability to stop competitors from marketing the same or similar products or limit the length of term of patent protection that we may have for our products.

Periodic maintenance fees, renewal fees, annuity fees and various other governmental fees on patents and/or patent applications will be due to be paid to the U.S. Patent and Trademark Office ("USPTO") and various governmental patent agencies outside of the U.S. in several stages over the lifetime of the applicable patent and/or patent application. The USPTO and various non-U.S. governmental patent agencies require compliance with a number of procedural, documentary, fee payment and other similar provisions during the patent application process. In many cases, an inadvertent lapse can be cured by payment of a late fee or by other means in accordance with the applicable rules. However, there are situations in which noncompliance can result in abandonment or lapse of the patent or patent application, resulting in partial or complete loss of patent rights in the relevant jurisdiction. If this occurs with respect to our in-licensed patents or patent applications we may file in the future, our competitors might be able to use our technologies, which would have a material adverse effect on our business, financial condition and results of operations.

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The patent positions of pharmaceutical products are often complex and uncertain. The breadth of claims allowed in pharmaceutical patents in the U.S. and many jurisdictions outside of the U.S. is not consistent. For example, in many jurisdictions, the support standards for pharmaceutical patents are becoming increasingly strict. Some countries prohibit method of treatment claims in patents. Changes in either the patent laws or interpretations of patent laws in the U.S. and other countries may diminish the value of our licensed or owned intellectual property or create uncertainty. In addition, publication of information related to our current product candidates and potential products may prevent us from obtaining or enforcing patents relating to these product candidates and potential products, including without limitation composition-of-matter patents, which are generally believed to offer the strongest patent protection.

Patents that we currently license and patents that we may own or license in the future do not necessarily ensure the protection of our licensed or owned intellectual property for a number of reasons, including, without limitation, the following:

• the patents may not be broad or strong enough to prevent competition from other products that are identical or similar to our product candidates;
• there can be no assurance that the term of a patent can be extended under the provisions of patent term extensions afforded by U.S. law or similar provisions in foreign countries, where available;
• the issued patents and patents that we may obtain or license in the future may not prevent generic entry into the market for our product candidates;
• we, or third parties from whom we in-license or may license patents, may be required to disclaim part of the term of one or more patents;
• there may be prior art of which we are not aware that may affect the validity or enforceability of a patent claim;
• there may be prior art of which we are aware, which we do not believe affects the validity or enforceability of a patent claim, but which, nonetheless, ultimately may be found to affect the validity or enforceability of a patent claim;
• there may be other patents issued to others that will affect our freedom to operate;
• if the patents are challenged, a court could determine that they are invalid or unenforceable;
• there might be a significant change in the law that governs patentability, validity and infringement of our licensed patents or any future patents we may own that adversely affects the scope of our patent rights;
• a court could determine that a competitor's technology or product does not infringe our licensed patents or any future patents we may own; and
• the patents could irretrievably lapse due to failure to pay fees or otherwise comply with regulations or could be subject to compulsory licensing.

If we encounter delays in our development or clinical trials, the period of time during which we could market our potential products under patent protection would be reduced.

Our competitors may be able to circumvent our licensed patents or future patents we may own by developing similar or alternative technologies or products in a non-infringing manner. Our competitors may seek to market generic versions of any approved products by submitting abbreviated new drug applications to the FDA in which our competitors claim that our licensed patents or any future patents we may own are invalid, unenforceable or not infringed. Alternatively, our competitors may seek approval to market their own products similar to or otherwise competitive with our products. In these circumstances, we may need to defend or assert our licensed patents or any future patents we may own, including by filing lawsuits alleging patent infringement. In any of these types of proceedings, a court or other agency with jurisdiction may find our licensed patents or any future patents we may own invalid or unenforceable. We may also fail to identify patentable aspects of our research and development before it is too late to obtain patent protection. Even if we own or in- license valid and enforceable patents, these patents still may not provide protection against competing products or processes sufficient to achieve our business objectives.

The issuance of a patent is not conclusive as to its inventorship, scope, ownership, priority, validity or enforceability. In this regard, third parties may challenge our licensed patents or any future patents we may own in the courts or patent offices in the U.S. and abroad. Such challenges may result in loss of exclusivity or freedom to operate or in patent claims being narrowed, invalidated or held unenforceable, in whole or in part, which could limit our ability to stop others from using or commercializing similar or identical technology and products, or limit the duration of the patent protection of our technology and potential products. In addition, given the amount of time required for the development, testing and regulatory review of new product candidates, patents protecting such product candidates might expire before or shortly after such product candidates are commercialized.

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We may infringe the intellectual property rights of others, which may prevent or delay our drug development efforts and prevent us from commercializing or increase the costs of commercializing our products.

Our commercial success depends significantly on our ability to operate without infringing the patents and other intellectual property rights of third parties. For example, there could be issued patents of which we are not aware that our current or potential future product candidates infringe. There also could be patents that we believe we do not infringe, but that we may ultimately be found to infringe.

Moreover, patent applications are in some cases maintained in secrecy until patents are issued. The publication of discoveries in the scientific or patent literature frequently occurs substantially later than the date on which the underlying discoveries were made and patent applications were filed. Because patents can take many years to issue, there may be currently pending applications of which we are unaware that may later result in issued patents that our product candidates or potential products infringe. For example, pending applications may exist that claim or can be amended to claim subject matter that our product candidates or potential products infringe. Competitors may file continuing patent applications claiming priority to already issued patents in the form of continuation, divisional, or continuation-in-part applications, in order to maintain the pendency of a patent family and attempt to cover our product candidates.

Third parties may assert that we are employing their proprietary technology without authorization and may sue us for patent or other intellectual property infringement. These lawsuits are costly and could adversely affect our business, financial condition and results of operations and divert the attention of managerial and scientific personnel. If we are sued for patent infringement, we would need to demonstrate that our product candidates, potential products or methods either do not infringe the claims of the relevant patent or that the patent claims are invalid, and we may not be able to do this. Proving invalidity is difficult. For example, in the U.S., proving invalidity requires a showing of clear and convincing evidence to overcome the presumption of validity enjoyed by issued patents. Even if we are successful in these proceedings, we may incur substantial costs and the time and attention of our management and scientific personnel could be diverted in pursuing these proceedings, which could have a material adverse effect on us. In addition, we may not have sufficient resources to bring these actions to a successful conclusion. If a court holds that any third-party patents are valid, enforceable and cover our products or their use, the holders of any of these patents may be able to block our ability to commercialize our products unless we acquire or obtain a license under the applicable patents or until the patents expire.

We may not be able to enter into licensing arrangements or make other arrangements at a reasonable cost or on reasonable terms. Any inability to secure licenses or alternative technology could result in delays in the introduction of our products or lead to prohibition of the manufacture or sale of products by us. Even if we are able to obtain a license, it may be non-exclusive, thereby giving our competitors access to the same technologies licensed to us. We could be forced, including by court order, to cease commercializing the infringing technology or product. In addition, in any such proceeding or litigation, we could be found liable for monetary damages, including treble damages and attorneys' fees, if we are found to have willfully infringed a patent. A finding of infringement could prevent us from commercializing our product candidates or force us to cease some of our business operations, which could materially and adversely affect our business, financial condition and results of operations. Any claims by third parties that we have misappropriated their confidential information or trade secrets could have a similar material and adverse effect on our business, financial condition and results of operations. In addition, any uncertainties resulting from the initiation and continuation of any litigation could have a material adverse effect on our ability to raise the funds necessary to continue our operations.

We may be required to initiate litigation to enforce or defend our licensed and owned intellectual property. Lawsuits to protect our intellectual property rights can be very time consuming and costly. There is a substantial amount of litigation involving patent and other intellectual property rights in the biopharmaceutical industry generally. Such litigation or proceedings could substantially increase our operating expenses and reduce the resources available for development activities or any future sales, marketing or distribution activities.

In any infringement litigation, any award of monetary damages we receive may not be commercially valuable. Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of our confidential information could be compromised by disclosure during litigation. Moreover, there can be no assurance that we will have sufficient financial or other resources to file and pursue such infringement claims, which typically last for years before they are resolved. Further, any claims we assert against a perceived infringer could provoke these parties to assert counterclaims against us alleging that we have infringed their patents. Some of our competitors may be able to sustain the costs of such litigation or proceedings more effectively than we can because of their greater financial resources. Uncertainties resulting from the initiation and continuation of patent litigation or other proceedings could have a material adverse effect on our ability to compete in the marketplace.

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In addition, our licensed patents and patent applications, and patents and patent applications that we may apply for, own or license in the future, could face other challenges, such as interference proceedings, opposition proceedings, re-examination proceedings and other forms of post-grant review. Any of these challenges, if successful, could result in the invalidation of, or in a narrowing of the scope of, any of our licensed patents and patent applications and patents and patent applications that we may apply for, own or license in the future subject to challenge. Any of these challenges, regardless of their success, would likely be time consuming and expensive to defend and resolve and would divert our management and scientific personnel's time and attention.

As is the case with other biopharmaceutical companies, our success is heavily dependent on intellectual property, particularly patents. Obtaining and enforcing patents in the biopharmaceutical industry involves both technological and legal complexity and is costly, time-consuming and inherently uncertain. For example, the U.S. previously enacted and is currently implementing wide-ranging patent reform legislation. Specifically, on September 16, 2011, the Leahy-Smith America Invents Act (the "Leahy-Smith Act") was signed into law and included a number of significant changes to U.S. patent law, and many of the provisions became effective in March 2013. However, it may take the courts years to interpret the provisions of the Leahy-Smith Act, and the implementation of the statute could increase the uncertainties and costs surrounding the prosecution of our licensed and future patent applications and the enforcement or defense of our licensed and future patents, all of which could have a material adverse effect on our business, financial condition and results of operations.

In addition, the U.S. Supreme Court has ruled on several patent cases in recent years, either narrowing the scope of patent protection available in certain circumstances or weakening the rights of patent owners in certain situations. In addition to increasing uncertainty with regard to our ability to obtain patents in the future, this combination of events has created uncertainty with respect to the value of patents, once obtained. Depending on decisions by the U.S. Congress, the federal courts and the USPTO, the laws and regulations governing patents could change in unpredictable ways that would weaken our ability to obtain new patents or to enforce patents that we might obtain in the future.

Filing, prosecuting and defending patents on product candidates throughout the world would be prohibitively expensive. Competitors may use our licensed and owned technologies in jurisdictions where we have not licensed or obtained patent protection to develop their own products and, further, may export otherwise infringing products to territories where we may obtain or license patent protection, but where patent enforcement is not as strong as that in the U.S. These products may compete with our products in jurisdictions where we do not have any issued or licensed patents and any future patent claims or other intellectual property rights may not be effective or sufficient to prevent them from so competing.

Many companies have encountered significant problems in protecting and defending intellectual property rights in foreign jurisdictions. The legal systems of certain countries, particularly certain developing countries, do not favor the enforcement of patents and other intellectual property protection, particularly those relating to biopharmaceuticals, which could make it difficult for us to stop the infringement of our licensed patents and future patents we may own, or marketing of competing products in violation of our proprietary rights generally. Further, the laws of some foreign countries do not protect proprietary rights to the same extent or in the same manner as the laws of the U.S. As a result, we may encounter significant problems in protecting and defending our licensed and owned intellectual property both in the U.S. and abroad. For example, China currently affords less protection to a company's intellectual property than some other jurisdictions. As such, the lack of strong patent and other intellectual property protection in China may significantly increase our vulnerability regarding unauthorized disclosure or use of our intellectual property and undermine our competitive position. Proceedings to enforce our future patent rights, if any, in foreign jurisdictions could result in substantial cost and divert our efforts and attention from other aspects of our business.

In order to protect our proprietary and licensed technology and processes, we rely in part on confidentiality agreements with our corporate partners, employees, consultants, manufacturers, outside scientific collaborators and sponsored researchers and other advisors. These agreements may not effectively prevent disclosure of our confidential information and may not provide an adequate remedy in the event of unauthorized disclosure of confidential information. In addition, others may independently discover our trade secrets and proprietary information. Failure to obtain or maintain trade secret protection could adversely affect our competitive business position.

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We may be subject to claims that our employees, consultants or independent contractors have wrongfully used or disclosed confidential information of third parties.

We expect to employ individuals who were previously employed at other biopharmaceutical companies. Although we have no knowledge of any such claims against us, we may be subject to claims that we or our employees, consultants or independent contractors have inadvertently or otherwise used or disclosed confidential information of our employees' former employers or other third parties. Litigation may be necessary to defend against these claims. There is no guarantee of success in defending these claims, and even if we are successful, litigation could result in substantial cost and be a distraction to our management and other employees. To date, none of our employees have been subject to such claims.

Although we are not currently experiencing any claims challenging the inventorship of our licensed patents or our licensed or owned intellectual property, we may in the future be subject to claims that former employees, collaborators or other third parties have an interest in our licensed patents or other licensed or owned intellectual property as an inventor or co-inventor. For example, we may have inventorship disputes arise from conflicting obligations of consultants or others who are involved in developing our product candidates. Litigation may be necessary to defend against these and other claims challenging inventorship. If we fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights, such as exclusive ownership of, or right to use, valuable intellectual property. Such an outcome could have a material adverse effect on our business, financial condition and results of operations. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees.

Depending upon the timing, duration and specifics of FDA regulatory approval for our product candidates, one or more of our licensed U.S. patents or future U.S. patents that we may license or own may be eligible for limited patent term restoration under the Drug Price Competition and Patent Term Restoration Act of 1984, referred to as the Hatch-Waxman Amendments. The Hatch-Waxman Amendments permit a patent restoration term of up to five years as compensation for patent term lost during drug development and the FDA regulatory review process. This period is generally one-half the time between the effective date of an investigational new drug application ("IND") (falling after issuance of the patent), and the submission date of an NDA, plus the time between the submission date of an NDA and the approval of that application. Patent term restorations, however, cannot extend the remaining term of a patent beyond a total of 14 years from the date of product approval by the FDA.

The application for patent term extension is subject to approval by the USPTO, in conjunction with the FDA. It takes at least six months to obtain approval of the application for patent term extension. We may not be granted an extension because of, for example, failing to apply within applicable deadlines, failing to apply prior to expiration of relevant patents or otherwise failing to satisfy applicable requirements. Moreover, the applicable time period or the scope of patent protection afforded could be less than we request. If we are unable to obtain patent term extension or restoration or the term of any such extension is less than we request, the period during which we will have the right to exclusively market our product will be shortened and our competitors may obtain earlier approval of competing products, and our ability to generate revenues could be materially adversely affected.

The trading price of our common stock is likely to be volatile. Our stock price could be subject to wide fluctuations in response to a variety of factors, including the following:

• results from, and any delays in, planned clinical trials for our product candidates, or any other future product candidates, and the results of trials of competitors or those of other companies in our market sector;
• any delay in filing an NDA for any of our product candidates and any adverse development or perceived adverse development with respect to the FDA's review of that NDA;
• significant lawsuits, including patent or stockholder litigation;
• inability to obtain additional funding;
• failure to successfully develop and commercialize our product candidates;
• changes in laws or regulations applicable to our product candidates;

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• inability to obtain adequate product supply for our product candidates, or the inability to do so at acceptable prices;
• unanticipated serious safety concerns related to any of our product candidates;
• adverse regulatory decisions;
• introduction of new products or technologies by our competitors;
• failure to meet or exceed drug development or financial projections we provide to the public;
• failure to meet or exceed the estimates and projections of the investment community;
• the perception of the biopharmaceutical industry by the public, legislatures, regulators and the investment community;
• announcements of significant acquisitions, strategic partnerships, joint ventures or capital commitments by us or our competitors;
• disputes or other developments relating to proprietary rights, including patents, litigation matters and our ability to obtain patent protection for our licensed and owned technologies;
• additions or departures of key scientific or management personnel;
• changes in the market valuations of similar companies;
• general economic and market conditions and overall fluctuations in the U.S. equity market;
• public health crises, pandemics and epidemics, such as the COVID-19 pandemic;
• sales of our common stock by us or our stockholders in the future; and
• trading volume of our common stock.

In addition, the stock market in general, and small biopharmaceutical companies in particular, have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of these companies. Broad market and industry factors may negatively affect the market price of our common stock, regardless of our actual operating performance. Further, a decline in the financial markets and related factors beyond our control may cause our stock price to decline rapidly and unexpectedly.

We must continue to satisfy the Nasdaq Capital Market's continued listing requirements, including, among other things, a minimum closing bid price requirement of $1.00 per share for 30 consecutive business days. If a company fails for 30 consecutive business days to meet the $1.00 minimum closing bid price requirement, The Nasdaq Stock Market LLC ("Nasdaq") will send a deficiency notice to the company, advising that it has been afforded a "compliance period" of 180 calendar days to regain compliance with the applicable requirements.

A delisting of our common stock from the Nasdaq Capital Market could materially reduce the liquidity of our common stock and result in a corresponding material reduction in the price of our common stock. In addition, delisting could harm our ability to raise capital through alternative financing sources on terms acceptable to us, or at all, and may result in the potential loss of confidence by investors and employees.

On November 11, 2020, we received written notice from Nasdaq indicating that, for the last thirty consecutive business days, the bid price for our common stock had closed below the minimum $1.00 per share requirement for continued listing on the Nasdaq Capital Market under Nasdaq Listing Rule 5550(a)(2). In accordance with Nasdaq Listing Rule 5810(c)(3)(A), we were provided an initial period of 180 calendar days, or until May 10, 2021, to regain compliance. We regained compliance after the closing bid price of our common stock had been at $1.00 per share or greater for twenty consecutive business days, from December 10, 2020 through January 8, 2021.

In addition, we have previously received similar notices from Nasdaq that our bid price of our common stock had closed below the minimum $1.00 per share requirement for continued listing on the Nasdaq Capital Market under Nasdaq Listing Rule 5550(a)(2). Even though we regained compliance with the Nasdaq Capital Market's minimum market value of listed securities requirement and minimum closing bid price requirement, there is no guarantee that we will remain in compliance with such listing requirements or other listing requirements in the future. Any failure to maintain compliance with continued listing requirements of the Nasdaq Capital Market could result in delisting of our common stock from the Nasdaq Capital Market and negatively impact our company and holders of our common stock, including by reducing the willingness of investors to hold our common stock because of the resulting decreased price, liquidity and trading of our common stock, limited availability of price quotations and reduced news and analyst coverage. Delisting may adversely impact the perception of our financial condition, cause reputational harm with investors, our employees and parties conducting business with us and limit our access to debt and equity financing.

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Our management owns a significant percentage of our stock and will be able to exert significant control over matters subject to stockholder approval.

As of March 4, 2021, Dr. Mehra, our sole executive officer and a director, owns approximately 4.4% of our outstanding common stock. Therefore, Dr. Mehra will have the ability to influence us through this ownership position.

This significant concentration of stock ownership may adversely affect the trading price for our common stock because investors often perceive disadvantages in owning stock in companies that have stockholders with substantial ownership positions. As a result, Dr. Mehra could significantly influence or determine all matters requiring approval by our stockholders, including the election of directors and the approval of mergers or other business combination transactions. The interests of these stockholders may not always coincide with our interests or the interests of other stockholders. This may also prevent or discourage unsolicited acquisition proposals or offers for our common stock that you may feel are in your best interests as one of our stockholders and he may act in a manner that advances his best interests and not necessarily those of other stockholders, including seeking a premium value for his common stock, and might affect the prevailing market price for our common stock.

The Sarbanes-Oxley Act, the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (the "Dodd-Frank Act") as well as rules subsequently implemented by the SEC and Nasdaq have imposed various requirements on public companies. There are significant corporate governance and executive compensation related provisions in the Dodd-Frank Act that require the SEC to adopt additional rules and regulations in these areas. Stockholder activism, the current political environment and the current high level of government intervention and regulatory reform may lead to substantial new regulations and disclosure obligations, which may lead to additional compliance costs and impact (in ways we cannot currently anticipate) the manner in which we operate our business. Our management and other personnel will need to devote a substantial amount of time to these compliance initiatives. Moreover, these rules and regulations will increase our legal and financial compliance costs and will make some activities more time-consuming and costly. For example, we expect these rules and regulations to make it more difficult and more expensive for us to obtain director and officer liability insurance and we may be required to incur substantial costs to maintain our current levels of such insurance coverage.

As a publicly traded company, we will incur legal, accounting and other expenses associated with the SEC reporting requirements applicable to a company whose securities are registered under the Exchange Act, as well as corporate governance requirements, including those under the Sarbanes-Oxley Act, the Dodd-Frank Act and other rules implemented by the SEC and Nasdaq. The expenses incurred by public companies generally to meet SEC reporting, finance and accounting and corporate governance requirements have been increasing in recent years as a result of changes in rules and regulations and the adoption of new rules and regulations applicable to public companies.

Sales of a substantial number of shares of our common stock by our existing stockholders in the public market, or the perception that these sales might occur, could depress the market price of our common stock and could impair our ability to raise capital through the sale of additional equity securities. We are unable to predict the effect that such sales may have on the prevailing market price of our common stock. As of March 4, 2021, we have outstanding warrants to purchase an aggregate of approximately 9.0 million shares of our common stock, which, if exercised, would further increase the number of shares of our common stock outstanding and the number of shares eligible for resale in the public market.

On October 16, 2018, we entered into a Securities Purchase Agreement with the investors listed on the Schedule of Buyers attached thereto, as amended, pursuant to which, among other things, we issued warrants to purchase shares of our common stock (the "Financing Warrants").

The outstanding Financing Warrants contain price-based adjustment provisions, pursuant to which the exercise price of the Financing Warrants may be adjusted downward in the event of certain dilutive issuances by us.

If the Financing Warrants are exercised, additional shares of our common stock will be issued, which will result in dilution to our then-existing stockholders and increase the number of shares eligible for resale in the public market. As of March 4, 2021, the Financing Warrants were exercisable for approximately 0.3 million shares of our common stock at an exercise price of

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$0.2957 per share of common stock. Sales of substantial numbers of such shares in the public market could depress the market price of our common stock.

Anti-takeover provisions in our governing documents and under Nevada law could make an acquisition of us more difficult and may prevent attempts by our stockholders to replace or remove our management.

Provisions in our articles of incorporation and bylaws may delay or prevent an acquisition or a change in management. These provisions include a classified board of directors and the ability of the board of directors to issue preferred stock without stockholder approval. Although we believe these provisions collectively will provide for an opportunity to receive higher bids by requiring potential acquirers to negotiate with our board of directors, they would apply even if the offer may be considered beneficial by some stockholders. In addition, these provisions may frustrate or prevent any attempts by our stockholders to replace or remove then current management by making it more difficult for stockholders to replace members of the board of directors, which is responsible for appointing the members of management.

Certain provisions of Nevada corporate law deter hostile takeovers. Specifically, Nevada Revised Statutes ("NRS") 78.411 through 78.444 prohibit a publicly held Nevada corporation from engaging in a "combination" with an "interested stockholder" for a period of two years following the date the person first became an interested stockholder, unless (with certain exceptions) the "combination" or the transaction by which the person became an interested stockholder is approved in a prescribed manner. Generally, a "combination" includes a merger, asset or stock sale, or certain other transactions resulting in a financial benefit to the interested stockholder. Generally, an "interested stockholder" is a person who, together with affiliates and associates, beneficially owns or within two years prior to becoming an "interested stockholder" did own, 10% or more of a corporation's voting power. While these statutes permit a corporation to opt out of these protective provisions in its articles of incorporation, our articles of incorporation do not include any such opt-out provision.

Nevada's "acquisition of controlling interest" statutes, NRS 78.378 through 78.3793, contain provisions governing the acquisition of a controlling interest in certain Nevada corporations. These "control share" laws provide generally that any person that acquires a "controlling interest" in certain Nevada corporations may be denied voting rights, unless a majority of the disinterested stockholders of the corporation elects to restore such voting rights. These statutes provide that a person acquires a "controlling interest" whenever a person acquires shares of a subject corporation that, but for the application of these provisions of the NRS, would enable that person to exercise (1) one-fifth or more, but less than one-third, (2) one-third or more, but less than a majority or (3) a majority or more, of all of the voting power of the corporation in the election of directors. Once an acquirer crosses one of these thresholds, shares that it acquired in the transaction taking it over the threshold and within the 90 days immediately preceding the date when the acquiring person acquired or offered to acquire a controlling interest become "control shares" to which the voting restrictions described above apply. While these statutes permit a corporation to opt out of these protective provisions in its articles of incorporation or bylaws, our articles of incorporation and bylaws do not include any such opt-out provision.

Further, NRS 78.139 also provides that directors may resist a change or potential change in control of the corporation if the board of directors determines that the change or potential change is opposed to or not in the best interest of the corporation upon consideration of any relevant facts, circumstances, contingencies or constituencies pursuant to NRS 78.138(4).

In general, a corporation that undergoes an "ownership change" as defined in Section 382 of the United States Internal Revenue Code of 1986, as amended, is subject to limitations on its ability to utilize its pre-change net operating loss carryforwards to offset future taxable income. In general, an ownership change occurs if the aggregate stock ownership of certain stockholders, generally stockholders beneficially owning five percent or more of a corporation's common stock, applying certain look-through and aggregation rules, increases by more than 50 percentage points over such stockholders' lowest percentage ownership during the testing period, generally three years. We may have experienced ownership changes in the past and may experience ownership changes in the future. It is possible that our net operating loss carryforwards and certain other tax attributes may also be subject to limitation as a result of ownership changes in the past and/or the closing of the Merger. Consequently, even if we achieve profitability, we may not be able to utilize a material portion of our net operating loss carryforwards and certain other tax attributes, which could have a material adverse effect on cash flow and results of operations.

We currently anticipate that we will retain future earnings for the development, operation and expansion of our business and does not anticipate it will declare or pay any cash dividends for the foreseeable future. Any return to stockholders will therefore be limited to the appreciation of their stock.

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General Risk Factors

If no active trading market for our common stock is sustained, you may be unable to sell your shares when you wish to sell them or at a price that you consider attractive or satisfactory. The lack of an active market may also adversely affect our ability to raise capital by selling securities in the future or impair our ability to acquire or in-license other product candidates, businesses or technologies using our shares as consideration.

Our management is required to report on the effectiveness of our internal control over financial reporting. The rules governing the standards that must be met for our management to assess our internal control over financial reporting are complex and require significant documentation, testing and possible remediation.

In connection with the implementation of the necessary procedures and practices related to internal control over financial reporting, we may identify deficiencies or material weaknesses that we may not be able to remediate in time to meet the deadline imposed by the Sarbanes-Oxley Act for compliance with the requirements of Section 404. In addition, we may encounter problems or delays in completing the implementation of any requested improvements and, when required, receiving a favorable attestation in connection with the attestation provided by our independent registered public accounting firm. Failure to achieve and maintain an effective internal control environment could have a material adverse effect on our business, financial condition and results of operations and could limit our ability to report our financial results accurately and in a timely manner.

The trading market for our common stock depends, in part, on the research and reports that securities or industry analysts publish about us or our business. If one or more of the analysts who cover us downgrade our stock or publish inaccurate or unfavorable research about our business, our stock price would likely decline. In addition, if our operating results fail to meet the forecast of analysts, our stock price would likely decline. If one or more of these analysts cease coverage of us or fail to publish reports on us regularly, demand for our common stock could decrease, which might cause our stock price and trading volume to decline.

None.

We currently lease one corporate office property in New York, New York, as our corporate office space for approximately 300 square feet. We believe that our leased facility is generally well maintained and in good operating condition and that the space is suitable and sufficient for our operational needs.

We may be a party to certain other litigation that is either judged to be not material or that arises in the ordinary course of business from time to time. We intend to vigorously defend our interests in these matters. We expect that the resolution of these matters will not have a material adverse effect on our business, financial condition or results of operations. However, due to the uncertainties inherent in litigation, no assurance can be given as to the outcome of these proceedings.

ITEM 4. MINE SAFETY DISCLOSURES?

Not applicable.

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PART II.

Our common stock is traded on the Nasdaq Capital Market under the symbol "SEEL." Before January 24, 2019, our common stock was trading under the ticker symbol "APRI". The daily market activity and closing prices of our common stock can be found at www.nasdaq.com.

On March 4, 2021, the last reported sales price for our common stock on the Nasdaq Capital Market was $2.66 per share, and we had approximately 104 holders of record of our common stock. One of our shareholders is Cede & Co., a nominee for Depository Trust Company ("DTC"). Shares of common stock that are held by financial institutions as nominees for beneficial owners are deposited into participant accounts at DTC, and are considered to be held of record by Cede & Co. as one stockholder.

We have never declared or paid cash dividends on our common stock and do not anticipate paying cash dividends on our common stock in the foreseeable future. The payment of dividends on our capital stock will depend on our earnings, financial condition and other business and economic factors affecting us at such time as our board of directors may consider relevant. If we do not pay dividends, our common stock may be less valuable because a return on your investment will only occur if the common stock price appreciates.

None.

Not applicable.

We are a clinical-stage biopharmaceutical company focused on achieving efficient development of products that address significant unmet needs in Central Nervous System ("CNS") disorders, and other rare disorders.

In March 2020, we began taking precautionary measures to protect the health and safety of our employees and contractors and further assessing the actual and potential impact of the coronavirus ("COVID-19") pandemic on our business, financial condition and operations. COVID-19 infections have been reported throughout the United States, along with other jurisdictions in which our suppliers, partners and collaborators operate. In addition, COVID-19 has caused disruption and volatility in the global capital markets, and has led to an economic slowdown. Certain national, provincial, state and local governmental authorities have issued proclamations and/or directives aimed at minimizing the spread of COVID-19 and additional, more restrictive proclamations and/or directives may be issued in the future. Before the recent COVID-19 outbreak, most of our employees worked remotely. In addition, our clinical trial for SLS-002 in ASIB in MDD completed the clinical testing phase in February 2020. On June 23, 2020, we released the final pharmacokinetics/pharmacodynamics portion of the data. Also, we did

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not experience any significant delays with opening our clinical sites for SLS-002 during the fourth quarter of 2020 and have not experienced any such delays during the first quarter of 2021 to date. Accordingly, the impact of the travel restrictions and shelter-in-place orders have not had a material impact on our operations to date. Additionally, the pandemic has not materially affected our liquidity as we maintain our resources in the form of cash.

In addition, although we do not currently expect the preventative measures taken to date to have a material adverse impact on our business for the first half of 2021, the ultimate impact of the COVID-19 pandemic on our business, financial condition and results of operations is unknown and will depend on future developments and risks, which are highly uncertain and cannot be predicted. These developments and risks include, among others, the duration and severity of the COVID-19 pandemic, the impact on capital markets, the impact on our partners and the regulatory agencies that oversee our sector and any additional preventative and protective actions that governmental authorities, or we, may implement, any of which may result in an extended period of business disruption, including potential delays in commencing future clinical trials, or in completing enrollment for any clinical trials we may commence or in the FDA or other regulatory agencies conducting in-person inspections or accommodations for alternatives to in-person inspections. Any resulting financial impact cannot be reasonably estimated at this time, but the COVID-19 pandemic may force us to make adjustments to our business, our plans and our timeline for developing assets, including our programs. In addition, the pandemic is currently not anticipated to have a material adverse impact on our business, financial condition and results of operations, including our ability to raise additional capital. However, if the pandemic continues at its current rate into the second quarter of 2021, it could have a material adverse impact on our business.

On January 24, 2019, Apricus completed the Merger with STI. Upon completion of the Merger, we changed our name to Seelos Therapeutics, Inc. and focused on the development and commercialization of CNS therapeutics with known mechanisms of action in areas with a highly unmet medical need. Also, on January 23, 2019, in connection with, and prior to the completion of, the Merger, we effected the Reverse Stock Split. Shares of our common stock commenced trading on the Nasdaq Capital Market under the ticker symbol "SEEL" as of market open on January 24, 2019. Our previous ticker symbol was "APRI". See Note 1 to our consolidated financial statements for more information regarding the Merger.

Our business model is to advance multiple late-stage therapeutic candidates with proven mechanisms of action that address large markets with unmet medical needs and for which there is a strong economic and scientific rationale for development.

Our product development pipeline is as follows:

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Lead Programs

Our lead programs are currently SLS-002 for the treatment of acute suicidal ideation and behavior ("ASIB") in major depressive disorder ("MDD"), and SLS-005 for the potential treatment of Amyotrophic Lateral Sclerosis ("ALS"). SLS-005 for the potential treatment of Sanfilippo Syndromes currently requires additional natural history data, which is being explored.

SLS-002 is intranasal racemic ketamine with two investigational new drug applications ("INDs"), the lead program is focused on the treatment of ASIB in MDD. SLS-002 was originally derived from a Javelin Pharmaceuticals, Inc./Hospira, Inc. program with 16 clinical studies involving approximately 500 subjects. SLS-002 addresses an unmet need for an efficacious drug to treat suicidality in the United States. Traditionally, anti-depressants have been used in this setting but many of the existing treatments are known to contribute to an increased risk of suicidal thoughts in some circumstances, and if and when they are effective, it often takes weeks for the full therapeutic effect to be manifested. We believe there is a large opportunity in the United States and European markets for products in this space. Based on information gathered from the databases of the Agency for Healthcare Research and Quality, there were more than 500,000 visits to emergency rooms for suicide attempts in 2013 in the United States alone. Experimental studies suggest ketamine has the potential to be a rapid, effective treatment for refractory depression and suicidality.

The clinical development program for SLS-002 includes two parallel healthy volunteer studies (Phase I). We announced interim data from our Phase I study of SLS-002 during the quarterly period ended March 31, 2020. The study demonstrated that 90mg of SLS-002, when administered as a monotherapy and in combination with an oral antidepressant, was generally safe and well-tolerated. Further, in March 2020, we completed a Type C meeting with the FDA and received guidance to conduct a Phase II proof of concept study of SLS-002 for ASIB in patients with MDD, to support the further clinical development of this product candidate, together with nonclinical data under development.

As a result of the Type C meeting and the Fast Track designation for SLS-002 for the treatment of ASIB in patients with MDD, we believe we are well positioned to pursue the FDA's expedited programs for drug development and review.

On June 23, 2020, we announced the final safety data from our Phase I pharmacokinetics/pharmacodynamics study of intranasal racemic ketamine (SLS-002) as well as the planned design of a Phase II double blind, placebo-controlled Proof of Concept ("PoC") study for ASIB in patients with MDD. We initiated this PoC study in two parts: Part A is an open-label study of 16 patients, and will be followed by Part B, which is a double blind, placebo-controlled study of approximately 120 patients. On January 15, 2021, we announced dosing of the first patients in Part A of the PoC study.

SLS-005 is IV Trehalose, a protein stabilizer that crosses the blood-brain-barrier, activates autophagy and lysosomal biogenesis. Based on the pre-clinical and in-vitro studies, there is a sound scientific rationale for developing Trehalose for the treatment of ALS and other indications such as Sanfilippo syndromes. Trehalose is a low molecular weight disaccharide (.342 kDa) that protects against pathological processes in cells. It has been shown to penetrate muscle and cross the blood-brain-barrier. In animal models of several diseases associated with abnormal cellular-protein aggregation, it has been shown to reduce pathological aggregation of misfolded proteins as well as to activate autophagy pathways through the activation of Transcription Factor EB ("TFEB"), a key factor in lysosomal and autophagy gene expression. Activation of TFEB is an emerging therapeutic target for a number of diseases with pathologic accumulation of storage material.

Trehalose 90 mg/mL IV solution has demonstrated promising clinical potential in prior Phase II clinical development for oculopharyngeal muscular dystrophy ("OPMD") and spinocerebellar ataxia type 3 ("SCA3"), also known as Machado Joseph disease, with a good safety profile and encouraging efficacy results. Pathological accumulation of protein aggregates within

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cells, whether in the CNS or in muscle, eventually leads to loss of function and ultimately cell death. Prior preclinical studies indicate that this platform has the potential to prevent mutant protein aggregation in other devastating PolyA/PolyQ diseases.

We own two United States patents for parenteral administration of trehalose for patients with OPMD and SCA3, both of which are expected to expire in 2034. In addition, Orphan Drug Designation for OPMD and SCA3 has been secured in the United States and in the European Union ("EU"). In February 2019, we assumed a collaborative agreement, turned subsequently into a research grant, with Team Sanfilippo Foundation ("TSF"), a nonprofit medical research foundation founded by parents of children with Sanfilippo syndrome. On April 30, 2020, we were granted Orphan Drug Designation ("ODD") for SLS-005 in Sanfilippo syndrome from the FDA. SLS-005 was previously granted ODD from the FDA and European Medicines Agency for SCA3 and OPMD as well as Fast Track designation for OPMD. On April 22, 2020, we received a Notice of Allowance from the United States Patent and Trademark Office for our U.S. patent number 10,751,353 (application number 16/263,707) titled "COMPOSITIONS AND METHODS FOR TREATING AN AGGREGATION DISEASE OR DISORDER" for trehalose (SLS-005). The allowed claims cover the composition of matter and method of use for trehalose (SLS-005) for treating a disease or disorder selected from any one of the following: Spinal and bulbar muscular atrophy; Dentatombral-pallidoluysian atrophy; Pick's disease; corticobasal degeneration; progressive supranuclear palsy; frontotemporal dementia; or parkinsonism linked to chromosome 17. On May 15, 2020, we were granted Rare Pediatric Disease Designation ("RPDD") for SLS-005 in Sanfilippo syndrome from the FDA. RPDD is an incentive program created under the Federal Food, Drug, and Cosmetic Act to encourage the development of new therapies for the prevention and treatment of certain rare pediatric diseases. At present, we are initiating the startup activities for a clinical study in ALS. In December 2020, we announced the selection of SLS-005 for the Healey ALS platform trial led by the Harvard Medical School, Massachusetts. The Healey ALS platform trial is designed to study multiple potential treatments for ALS simultaneously. The platform trial model aims to greatly accelerate the study access, reduce costs and shorten development timelines.

Additionally, we are developing several preclinical programs, most of which have well-defined mechanisms of action, including: SLS-004, licensed from Duke University, and SLS-007, licensed from The Regents of the University of California, for the potential treatment of Parkinson's Disease ("PD"), SLS-008, targeted at chronic inflammation in asthma and orphan indications such as pediatric esophagitis, SLS-010 in narcolepsy and related disorders and SLS-012, an injectable therapy for post-operative pain management.

SLS-002: The clinical development program for SLS-002 includes two parallel healthy volunteer studies (Phase I). Following these Phase I studies, we completed a Type C meeting with the FDA in March 2020 and received guidance to conduct a Phase II proof of concept study of SLS-002 for ASIB in patients with MDD. The startup activities are underway and have enrolled several patients in Part A of our open-label study.

SLS-005 is undergoing startup activities for a clinical study in ALS. In December 2020, we announced the selection of SLS-005 for the Healey ALS platform trial led by the Harvard Medical School, Massachusetts. The Healey ALS platform trial is designed to study multiple potential treatments for ALS simultaneously. The platform trial model aims to greatly accelerate the study access, reduce costs, and shorten development timelines. We are continuing to explore trials in Sanfilippo syndromes and are seeking more natural history data based on the guidance from regulatory agencies.

SLS-004 is an all-in-one lentiviral vector, targeted for gene editing through DNA methylation within intron 1 of the SNCA gene responsible for expressing alpha-synuclein protein. SLS-004, when delivered to dopaminergic neurons derived from human induced pluripotent stem cells (hiPSCs) of a PD patient, modified the expression on alpha-synuclein and exhibited reversal of the disease-related cellular-phenotypes characteristics of the neurons. The role of mutated SNCA in PD pathogenesis and the need to maintain the normal physiological levels of alpha-synuclein protein emphasize the so-far unmet need to develop new therapeutic strategies, such as SLS-004, targeting the regulatory mechanism of alpha-synuclein expression. On May 28, 2020, we announced the initiation of a preclinical study of SLS-004 in PD through an all-in-one lentiviral vector targeting the synuclein alpha gene. We are constructing a bimodular viral system harboring an endogenous

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SLS-006 is a true partial dopamine agonist, originally developed by Wyeth Pharmaceuticals, Inc., with previous clinical studies on 340 subjects in various Phase I and Phase II studies. It is a potent D2/D3 agonist/antagonist that has shown promising efficacy with statistical significance in Phase II studies in early stage PD patients and an attractive safety profile. Moreover, it has also shown synergistic effect with reduced doses of L-DOPA. We are evaluating studies to advance the product candidate into late stage trials.

SLS-008 is an orally available antagonist for Chemoattractant Receptor-homologous molecules expressed on TH2 cells ("CRTh2"), targeted at chronic inflammation in asthma and a pediatric orphan indication. We have a "family" of compounds under our SLS-008 program. We intend to file an IND after completion of IND-enabling studies, which are currently in progress, in an undisclosed pediatric orphan indication where there is a high unmet need for an effective oral therapy.

Additionally, we are developing several preclinical programs, most of which have well-defined mechanisms of action, including:

• SLS-010, an oral histamine H3A receptor antagonist that shows promising activity in narcolepsy and related disorders; and
• SLS-012, an injectable therapy for post-operative pain management.

On February 15, 2019, we entered into the Bioblast Asset Purchase Agreement with Bioblast. Pursuant to the Bioblast Asset Purchase Agreement, we acquired all of the assets of Bioblast relating to a therapeutic platform known as Trehalose. We paid to Bioblast $1.5 million in cash in February 2019, and an additional $2.0 million in cash in February 2020. Under the terms of the Bioblast Asset Purchase Agreement, we agreed to pay additional consideration to Bioblast upon the achievement of certain milestones in the future, as follows: (1) within 15 days following the completion of our or our affiliate's first Phase II(b) clinical trial of Trehalose satisfying certain criteria, we will pay to Bioblast $8.5 million in cash; and (2) within 15 days following the approval for commercialization by the FDA or the Health Products and Food Branch of Health Canada of the first NDA or New Drug Submission, respectively, of Trehalose filed by us or our affiliates, we will pay to Bioblast $8.5 million in cash. In addition, we agreed to pay Bioblast a cash royalty equal to 1% of the net sales of Trehalose. Under the terms of the Bioblast Asset Purchase, we assumed a collaborative agreement with TSF, a nonprofit medical research foundation founded by parents of children with Sanfilippo syndrome. TSF, upon approval by the FDA, plans to begin a Phase II(b)/III clinical trial in up to 24 patients with Sanfilippo syndrome, which is now known under the study name SLS-005. We will provide the clinical supply of Trehalose. The terms of the Bioblast Asset Purchase Agreement entitle us to access all clinical data from this trial. On July 15, 2019, we amended the agreement whereby we agreed to assume responsibility for the Phase II(b)/III clinical trial and TSF agreed to provide a grant of up to $1.5 million towards the funding of the trial.

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Acquisition of License from The Regents of the University of California

On June 27, 2019, we entered into the Duke License Agreement pursuant to which we were granted an exclusive license to a gene therapy program targeting the regulation of the SNCA gene, which encodes alpha-synuclein expression. We plan to study this initial approach in PD and will further evaluate the potential clinical approach in other disorders affecting the CNS. This program is now known as SLS-004. Upon entry into the Duke License Agreement, we paid to Duke University $0.1 million. Under the terms of the Duke License Agreement, we agreed to pay additional consideration to Duke University upon the achievement of certain milestones in the future, as follows: (i) within 30 days following filing of an IND following the completion of preclinical studies including comprehensive validation of the platform, we will pay $0.1 million; (ii) within 30 days following dosing of the first patient in a Phase I clinical trial, we will pay $0.2 million; (iii) within 30 days following dosing of the first patient in a Phase II clinical trial, we will pay $0.5 million; (iv) within 30 days following dosing of the first patient in a Phase III clinical trial, we will pay $1.0 million; and (v) within 30 days following an NDA approval, we will pay $2.0 million. We are also obligated to pay a single digit royalty on sales of the product, if any. In addition, if we fail to achieve certain milestones within a specified timeframe, Duke University may terminate the agreement.

We intend to become a leading biopharmaceutical company focused on neurological and psychiatric disorders, including orphan indications. Our business strategy includes:

• Advancing SLS-002 in ASIB in MDD and PTSD;
• Advancing SLS-004 in PD;
• Advancing SLS-005 in ALS and Sanfilippo syndrome;
• Advancing SLS-007 in PD as a monotherapy;
• Filing an IND for SLS-008 in an undisclosed indication;
• Forming strategic collaborations in the EU and Asian markets; and
• Acquiring synergistic assets in the central nervous system therapy space through licensing and partnerships.

We also have two legacy product candidates: a product candidate in the United States for the treatment of ED, which we in-licensed from Warner Chilcott Company, Inc., now a subsidiary of Allergan; and a product candidate which has completed a Phase IIa clinical trial for the treatment of Raynaud's Phenomenon, secondary to scleroderma, for which we own worldwide rights.

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Results of Operations

We recorded $0 and $375,000 in grant revenue during the year ended December 31, 2020 and 2019, respectively. The $375,000 in revenue in 2019 was related to our amended agreement with TSF, pursuant to which we agreed to assume responsibility for the Phase II(b)/III clinical trial and TSF agreed to provide a grant of up to $1.5 million towards the funding of the trial.

Operating expense was as follows (in thousands, except percentages):

Research and development ("R&D") costs are expensed as they are incurred and include the cost of compensation and related expenses, as well as expenses for third parties who conduct R&D on our behalf. The $11.6 million decrease in R&D expense during the year ended December 31, 2020, as compared to the same period in 2019, are as follows (in thousands, except percentages):

The $11.6 million decrease in R&D expense during the year ended December 31, 2020, as compared to the same period in 2019, resulted primarily from a decrease in license fees of approximately $13.8 million and manufacturing costs of approximately $914,000. These decreases were partially offset by increases in clinical trial costs of approximately $2.0 million and external consulting costs of approximately $705,000.

General and administrative ("G&A") costs include expenses for personnel, finance, legal, business development and investor relations. G&A expenses increased by $216,000 during the year ended December 31, 2020, as compared to the same period in 2019. This increase was primarily due to non-cash stock-based compensation of approximately $1.3 million and costs including, but not limited to, investor relations costs of approximately $401,000 and patent maintenance and external legal costs of approximately $319,000 during the year ended December 31, 2020. This increase was partially offset by decreases in legal and administrative costs associated with the Merger incurred during the year ended December 31, 2019 of $2.0 million.

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Other Income and Expense

Other income and expense was as follows (in thousands):

Interest income was $45,000 and $151,000 for the year ended December 31, 2020 and 2019, respectively. The decrease in interest income primarily related to the lower average cash balances along with lower interest rates earned during the year ended December 31, 2020 compared to the year ended December 31, 2019.

Interest expense was $164,000 and $29,000 for the year ended December 31, 2020 and 2019, respectively. The increase is due to the issuance of certain convertible notes in December 2020 (see below).

Loss on warrant issuance was $0 and $5.0 million for the year ended December 31, 2020 and 2019, respectively. The loss was due to the fair value of the warrants exceeding the net cash proceeds from the Merger.

The fair value of warrant liability was $1.1 million and $963,000 at December 31, 2020 and 2019, respectively. The change in fair value of warrant liabilities of $223,000 and $16.5 million during the year ended December 31, 2020 and 2019, respectively, is due to revaluation of the two series of warrants to purchase shares of common stock issued on January 24, 2019 (the "Series A Warrants" and the "Series B Warrants" and, together, the "Pre-Merger Warrants") pursuant to that certain Securities Purchase Agreement, dated October 16, 2018, by and among Apricus, STI and the investors listed on the Schedule of Buyers attached thereto (the "Pre-Merger SPA").

The convertible notes were converted into common stock pursuant to the Merger on January 24, 2019. The change in fair value of convertible notes was an expense of $0 and $109,000 during the year ended December 31, 2020 and 2019, respectively.

We have generated limited revenues, incurred operating losses since inception, and we expect to continue to incur significant operating losses for the foreseeable future and may never become profitable. As of December 31, 2020, we had $15.7 million in cash and an accumulated deficit of $75.2 million. We have historically funded our operations through the issuance of convertible notes (the "Notes") (see Note 7 to our consolidated financial statements), the sale of common stock (see Note 4 to our consolidated financial statements) and the exercise of warrants (see Note 8 to our consolidated financial statements).

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On January 28, 2021, we completed an underwritten public offering pursuant to which we sold 17,530,488 shares of our common stock at a price to the public of $2.05 per share, which included the exercise in full by the underwriter of its option to purchase up to 2,286,585 additional shares of common stock. The net proceeds to us from the offering were approximately $33.5 million, after deducting underwriting discounts and commissions and other estimated offering expenses payable by us. We used $3.8 million of the net proceeds from the offering for the partial repayment of the Notes (as defined below).

On December 11, 2020, we entered into a Securities Purchase Agreement (the "Lind Securities Purchase Agreement") with Lind Global Asset Management II, LLC (the "Investor") pursuant to which, among other things, on December 11, 2020, we issued and sold to the Investor, in a private placement transaction, in exchange for the payment by the Investor of $10,000,000, (1) a convertible promissory note (the "Note") in an aggregate principal amount of $12,000,000 (the "Principal Amount"), which will bear no interest and mature on December 11, 2022 (the "Maturity Date"), and (2) 975,000 shares (the "Closing Shares") of our common stock. At any time following June 11, 2021, and from time to time before the Maturity Date, the Investor shall have the option to convert any portion of the then-outstanding Principal Amount of the Note into shares of common stock at a price per share of $1.60, subject to adjustment for stock splits, reverse stock splits, stock dividends and similar transactions (the "Conversion Price"). Prior to June 11, 2021, we will have the right to prepay up to sixty-six and two-thirds percent (66^2/3%) of the then-outstanding Principal Amount of the Note with no penalty. On or after July 11, 2021, we will have the right to prepay up to the then-outstanding Principal Amount of the Note with no penalty; however, if we exercise such prepayment right, the Investor will have the option to convert up to thirty-three and one-third percent (33^1/3%) of the amount that we elect to prepay at the Conversion Price. Subject to certain exceptions, we will be required to direct proceeds from any subsequent debt financings (including subordinated debt, convertible debt or mandatorily redeemable preferred stock but other than purchase money debt or capital lease obligations or other indebtedness incurred in the ordinary course of business) to repay the Note, unless waived by the Investor in advance. Beginning on June 9, 2021, the Note will amortize in eighteen monthly installments equal to the quotient of (i) the then-outstanding Principal Amount of the Note, divided by (ii) the number of months remaining until the Maturity Date. All amortization payments shall be payable solely in cash, plus a 2% premium.

On December 17, 2020, we entered into three separate securities purchase agreements with certain accredited investors on substantially the same terms as the Lind Securities Purchase Agreement (the "December 17 SPAs"), pursuant to which we sold, in private placement transactions, in exchange for the payment by the accredited investors of an aggregate of $1,138,023.16, (1) convertible promissory notes (the "December 17 Notes") in an aggregate principal amount of $1,365,627.80, which will bear no interest and mature on December 17, 2022, and (2) an aggregate of 110,956 shares of our common stock. On December 18, 2020, we entered into an additional securities purchase agreement with an accredited investor on substantially the same terms as the Lind Securities Purchase Agreement (the "December 18 SPA" and, together with the December 17 SPAs, the "Subsequent Securities Purchase Agreements"), pursuant to which we sold, in a private placement transaction, in exchange for the payment by the accredited investor of $269,372.50, (1) a convertible promissory note (the "December 18 Note" and, together with the December 17 Notes, the "Subsequent Notes," and, together with the Note, the "Notes") in an aggregate principal amount of $323,247, which will bear no interest and mature on December 18, 2022, and (2) 26,263 shares of our common stock. The Subsequent Securities Purchase Agreements were entered into with certain accredited investors pursuant to the right to participate in future offerings provided to the accredited investors in connection with the registered direct offering we completed in September 2020. The Subsequent Securities Purchase Agreements have substantially the same terms as the Lind Securities Purchase Agreement, and the Subsequent Notes have substantially the same terms as the Note. In connection with the Subsequent Securities Purchase Agreements, we repaid $1.4 million of principal amount of the Note on January 8, 2021.

On September 4, 2020, we entered into a Securities Purchase Agreement with certain institutional investors (the "September 2020 Securities Purchase Agreement"), pursuant to which we issued and sold an aggregate of 8,865,000 shares of common stock in a registered direct offering, resulting in total gross proceeds of approximately $6.4 million, after deducting the placement agent's fees and offering expenses (see Note 4 to our consolidated financial statements). We also agreed to issue to the investors unregistered warrants to purchase up to 6,648,750 shares of common stock in a concurrent private placement (the "September 2020 Warrants"). The September 2020 Warrants have an exercise price of $0.84 per share of common stock, will be exercisable six months from the date of issuance and will expire on March 9, 2026. The combined purchase price for one share and one warrant to purchase half of a share of common stock in the offerings was $0.79.

On May 4, 2020, we qualified for and received a loan pursuant to the Paycheck Protection Program, a program implemented by the U.S. Small Business Administration under the Coronavirus Aid, Relief, and Economic Security Act, from a qualified lender (the "PPP Lender"), for an aggregate principal amount of approximately $147,000 (the "PPP Loan"). The PPP Loan bears interest at a fixed rate of 1.0% per annum, with the first six months of interest deferred, has a term of two years and is unsecured and guaranteed by the U.S. Small Business Administration. The principal amount of the PPP Loan is subject to forgiveness under the Paycheck Protection Program upon our request to the extent that the PPP Loan proceeds are used to pay

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expenses permitted by the Paycheck Protection Program, including payroll costs, covered rent and mortgage obligations and covered utility payments incurred by us. We intend to apply for forgiveness of the PPP Loan with respect to these covered expenses. To the extent that all or part of the PPP Loan is not forgiven, we will be required to pay interest on the PPP Loan at a rate of 1.0% per annum, and commencing in the fourth quarter of 2020, principal and interest payments will be required through the maturity date in May 2022. The terms of the PPP Loan provide for customary events of default including, among other things, payment defaults, breach of representations and warranties and insolvency events. The obligation to repay the PPP Loan may be accelerated upon the occurrence of an event of default.

On March 16, 2020, we completed an underwritten public offering pursuant to which we sold 7,500,000 shares of our common stock at a price to the public of $0.60 per share. The net proceeds to us from this offering were approximately $4.0 million, after deducting underwriting discounts and commissions and other offering expenses payable by us.

On February 13, 2020, we completed an underwritten public offering, pursuant to which we sold 6,666,667 shares of our common stock at a price to the public of $0.75 per share. On February 19, 2020, we sold an additional 999,999 shares of our common stock at a price to the public of $0.75 per share pursuant to the full exercise of the underwriters' option to cover over-allotments. The net proceeds to us from this offering were approximately $5.0 million, after deducting underwriting discounts and commissions and other estimated offering expenses payable by us.

On August 23, 2019, we entered into a Securities Purchase Agreement with certain institutional investors (the "August 2019 Securities Purchase Agreement"), pursuant to which we issued and sold an aggregate of 4,475,000 shares of common stock in a registered direct offering, resulting in total gross proceeds of approximately $6.7 million, before deducting the placement agents' fees and other estimated offering expenses (see Note 4 to our consolidated financial statements). We also agreed to issue to the investors unregistered warrants to purchase up to 2,237,500 shares of common stock in a concurrent private placement (the "August 2019 Warrants"). The August 2019 Warrants have an exercise price of $1.78 per share of common stock, will be exercisable six months from the date of issuance and will expire four years following the date of issuance. The combined purchase price for one share and one warrant to purchase half of a share of common stock in the offerings was $1.50.

On June 17, 2019, we entered into an Equity Distribution Agreement (the "Equity Distribution Agreement") with Piper Jaffray & Co., as sales agent ("Piper Jaffray"), pursuant to we may offer and sell, from time to time, through Piper Jaffray up to $50,000,000 in shares of our common stock. During the year ended December 31, 2019, we sold 1,197,676 shares for net proceeds of approximately $2.6 million pursuant to the Equity Distribution Agreement (see Note 4 to our consolidated financial statements). On August 23, 2019, we suspended our continuous offering under the Equity Distribution Agreement and the Equity Distribution Agreement terminated in accordance with its terms on December 7, 2020.

During the year ended December 31, 2020 and 2019, we received approximately $45 thousand and $4.5 million, respectively, in proceeds from the exercise of approximately 154 thousand and 14.3 million Series A Warrants and Series B Warrants, respectively.

We expect to use the net proceeds from the above transactions primarily for general corporate purposes, which may include financing our normal business operations, developing new or existing product candidates, and funding capital expenditures, acquisitions and investments. In addition, pursuant to the amended and restated license agreement with Stuart Weg, M.D., if certain conditions are not met, make an additional cash payment of $0.2 million in January 2022. We believe that in order for us to meet our obligations arising from normal business operations for the next twelve months, we require additional capital in the form of equity, debt or both. Without additional capital, our ability to continue to operate will be limited. These financial statements do not include any adjustments to the recoverability and classification of recorded assets amounts and classification of liabilities that might be necessary should we not be able to continue as a going concern.

We currently have an effective shelf registration statement on Form S-3 filed with the SEC. We may use the shelf registration statement on Form S-3 of which this prospectus forms a part to offer from time to time any combination of debt securities, common and preferred stock and warrants, and, as of the date hereof, a total of $168.7 million of securities remains available for issuance pursuant to the shelf registration statement.

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The accompanying audited consolidated financial statements have been prepared assuming we will continue to operate as a going concern, which contemplates the realization of assets and settlement of liabilities in the normal course of business, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classifications of liabilities that may result from uncertainty related to our ability to continue as a going concern.

Our future liquidity and capital funding requirements will depend on numerous factors, including:

• our ability to raise additional funds to finance our operations;
• our ability to maintain compliance with the listing requirements of The Nasdaq Capital Market;
• the outcome, costs and timing of any clinical trial results for our current or future product candidates;
• potential litigation expenses;
• the emergence and effect of competing or complementary products or product candidates;
• our ability to maintain, expand and defend the scope of our intellectual property portfolio, including the amount and timing of any payments we may be required to make, or that we may receive, in connection with the licensing, filing, prosecution, defense and enforcement of any patents or other intellectual property rights;
• our ability to retain our current employees and the need and ability to hire additional management and scientific and medical personnel;
• the terms and timing of any collaborative, licensing or other arrangements that we have or may establish;
• the trading price of our common stock;
• our ability to secure a development partner for our product candidate in the United States for the treatment of ED; and
• our ability to increase the number of authorized shares outstanding to facilitate future financing events.

We will need to raise substantial additional funds through one or more of the following: issuance of additional debt, equity, or both and/or the completion of a licensing or other commercial transaction for one or more of our product candidates. If we are unable to maintain sufficient financial resources, our business, financial condition and results of operations will be materially and adversely affected. This could adversely affect future development and business activities, operations and business plans, such as future clinical studies and/or other future ventures. There can be no assurance that we will be able to obtain the needed financing on acceptable terms or at all. Additionally, equity or convertible debt financings may have a dilutive effect on the holdings of our existing stockholders. No assurances can be given that we will be able to obtain additional financing.

On November 11, 2020, we received written notice (the "Notice") from The Nasdaq Stock Market LLC ("Nasdaq") indicating that, for the last thirty consecutive business days, the bid price for our common stock had closed below the minimum $1.00 per share requirement for continued listing on the Nasdaq Capital Market under Nasdaq Listing Rule 5550(a)(2). In accordance with Nasdaq Listing Rule 5810(c)(3)(A), we were provided an initial period of 180 calendar days, or until May 10, 2021, to regain compliance. We regained compliance after the closing bid price of our common stock had been at $1.00 per share or greater for twenty consecutive business days, from December 10, 2020 through January 8, 2021.

The following table summarizes selected items in our consolidated statements of cash flows (in thousands):

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Operating Activities

Cash used in operating activities of $20.9 million in the year ended December 31, 2020 was primarily due to the net loss of $19.1 million and changes in operating assets and liabilities of $4.5 million, which was partially offset by $2.0 million in stock compensation expense.

Cash used in operating activities of $19.3 million in the year ended December 31, 2019 was primarily due to the net loss of $51.3 million, which was partially offset by changes in the fair value of the warrant liabilities of $16.5 million, changes in operating assets and liabilities of $6.9 million, $3.0 million in non-cash expense for the acquisition of licenses for research and development, and the loss on warrant issuance of $5.0 million.

No cash was used in investing activities during the years ended December 31, 2020 or 2019.

Cash provided by financing activities of $26.3 million in the year ended December 31, 2020 was primarily due to the proceeds from the exercise of warrants, the proceeds from the issuance and sale of the Note and the Closing Shares, the issuance and sale of common stock pursuant to the September 2020 Securities Purchase Agreement, the PPP Loan, and proceeds from our February 2020 and March 2020 public offerings.

Cash provided by financing activities of $29.5 million in the year ended December 31, 2019 was primarily due to the proceeds from the exercise of warrants, the proceeds from the issuance and sale of common stock pursuant to the August 2019 Securities Purchase Agreement, the proceeds from the issuance and sale of common stock and warrants pursuant to the Pre-Merger SPA and proceeds from the issuance and sale of common stock pursuant to the Equity Distribution Agreement.

We have entered into long-term agreements with certain manufacturers and suppliers that require us to make contractual payment to these organizations. We expect to enter into additional collaborative research, contract research, manufacturing, and supplier agreements in the future, which may require up-front payments and long-term commitments of cash.

The following represents our contractual obligations as of December 31, 2020 (in thousands):

(1)   Purchase obligations primarily represent commitments for agreements with external service providers, under which we will incur expenses relating to clinical trials of SLS-002 and SLS-005 and other clinical candidates. These agreements are cancellable on notice of up to three months.

As of December 31, 2020, we did not have any off-balance sheet arrangements as defined in Item 303(a)(4)(ii) of Regulation S-K.

See Note 1 to our consolidated financial statements for a discussion of recent accounting pronouncements and their effect, if any, on us.

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Critical Accounting Estimates and Policies

The preparation of financial statements in accordance with United States generally accepted accounting principles ("GAAP") requires management to make estimates and assumptions that affect the amounts reported in our consolidated financial statements and accompanying notes. Management bases its estimates on historical experience, market and other conditions, and various other assumptions it believes to be reasonable. Although these estimates are based on management's best knowledge of current events and actions that may impact us in the future, the estimation process is, by its nature, uncertain given that estimates depend on events over which we may not have control. If market and other conditions change from those that we anticipate, our consolidated financial statements may be materially affected. In addition, if our assumptions change, we may need to revise our estimates, or take other corrective actions, either of which may also have a material effect in our consolidated financial statements. We review our estimates, judgments, and assumptions used in our accounting practices periodically and reflect the effects of revisions in the period in which they are deemed to be necessary. We believe that these estimates are reasonable; however, our actual results may differ from these estimates.

We believe that the following critical accounting policies and estimates have a higher degree of inherent uncertainty and require our most significant judgments:

Research and development costs are expensed as incurred and include salaries and benefits; costs paid to third-party contractors to perform research, conduct clinical trials, develop and manufacture pre-approval drug materials and delivery devices. Clinical trial costs are a significant component of research and development expenses and include costs associated with third-party contractors. Invoicing from third-party contractors for services performed can lag several months. We accrue the costs of services rendered in connection with third-party contractor activities based on our estimate of management fees, site management and monitoring costs and data management costs. Differences between actual clinical trial costs from estimated clinical trial costs have not been material and are adjusted for in the period in which they become known.

Stock based compensation expense includes charges related to options awards to employees and directors. The estimated grant date fair value of stock options granted to employees and directors is calculated based upon the closing stock price of our common stock on the date of the grant and recognized as stock-based compensation expense over the expected service period, which is typically approximated by the vesting period.

We estimate the fair value of each option award on the date of grant using the Black-Scholes option pricing model. The Black-Scholes option pricing model requires us to estimate our dividend yield rate, expected volatility and risk-free interest rate over the life of the option. The use of estimates on these factors may cause the fair value of the option to be under or overestimated (see Note 9 to our consolidated financial statements for the current estimates used in the Black-Scholes option pricing model).

Our outstanding Series A Warrants are classified as liabilities in the accompanying consolidated balance sheets as they contain provisions that are considered outside of our control, such as requiring us to maintain active registration of the shares underlying such warrants. The warrants were recorded at fair value using the Black-Scholes option pricing model. The fair value of these warrants is re-measured at each financial reporting period with any changes in fair value being recognized as a component of other income (expense) in the accompanying consolidated statements of operations.

Not applicable.

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ITEM 8. FINANCIAL STATEMENTS

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Report of Independent Registered Public Accounting Firm

To the Stockholders and Board of Directors
Seelos Therapeutics, Inc.:

We have audited the accompanying consolidated balance sheets of Seelos Therapeutics, Inc. and subsidiaries (the Company) as of December 31, 2020 and 2019, 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, 2020, and the related notes (collectively, the consolidated financial statements). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2020 and 2019, and the results of its operations and its cash flows for each of the years in the two-year period ended December 31, 2020, in conformity with U.S. generally accepted accounting principles.

The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern. As discussed in Note 2 to the consolidated financial statements, the Company has suffered recurring losses from operations and has a net capital deficiency that raise substantial doubt about its ability to continue as a going concern. Management's plans in regard to these matters are also described in Note 2. The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty.

These consolidated financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on these consolidated financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits, we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company's internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical audit matters are matters arising from the current period audit of the consolidated financial statements that were communicated or required to be communicated to the audit committee and that: (1) relate to accounts or disclosures that are material to the consolidated financial statements and (2) involved our especially challenging, subjective, or complex judgments. We determined that there are no critical audit matters.

We have served as the Company's auditor since 2017

Short Hills, New Jersey
March 11, 2021