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ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The purpose of this Management's Discussion and Analysis is to better allow our investors to understand and view our company from management's perspective. We are providing an overview of our business and strategy including a discussion of our financial condition and results of operations. You should read the following discussion in conjunction with the consolidated financial statements and the notes to the consolidated financial statements included elsewhere in this Annual Report on Form 10-K. This discussion contains forward-looking statements within the meaning of federal securities laws. Such forward-looking statements are subject to risks and uncertainties that could cause actual results to differ materially from those contained in such forward-looking statements, including those discussed in the section “Risk Factors” in Part I — Item 1A of this Annual Report on Form 10-K.

Overview

We are a late-stage clinical biopharmaceutical company focused on the development of novel therapeutics for a broad range of cancer indications. Our product candidates currently include galinpepimut-S, or GPS, a peptide immunotherapy directed against the Wilms tumor 1, or WT1, antigen, and GFH009, a highly selective small molecule cyclin-dependent kinase 9, or CDK9, inhibitor.

Galinpepimut-S, or GPS: Highly Novel and Engineered Immunotherapy targeting the WT1 Antigen

Our lead product candidate, GPS, is a cancer immunotherapeutic agent licensed from Memorial Sloan Kettering Cancer Center, or MSK, that targets the WT1 protein, which is present in 20 or more cancer types. Based on its mechanism of action as a directly immunizing agent, GPS has potential as a monotherapy or in combination with other immunotherapeutic agents to address a broad spectrum of hematologic, or blood, cancers and solid tumor indications.

In January 2020, we commenced in the United States an open label randomized Phase 3 clinical trial, the REGAL study, for GPS monotherapy in patients with acute myeloid leukemia, or AML, in the maintenance setting after achievement of second complete remission, or CR2, following successful completion of second-line antileukemic therapy. Patients are randomized to receive either GPS or best available treatment, or BAT. We expect this study will be used as the basis for submission of a Biologics License Application, or BLA, subject to a statistically significant and clinically meaningful data outcome and agreement with the U.S. Food and Drug Administration, or the FDA. The primary endpoint of the clinical trial is overall survival. We plan to enroll approximately 125 to 140 patients at approximately 95 clinical sites in North America, Europe and Asia with a planned interim safety, efficacy and futility analysis after 60 events (deaths). Under our current assumptions with respect to completion of enrollment and the estimated survival times for both the treated and control groups in the study, we believe, after discussions with our external statisticians and experts, that the planned interim analysis after 60 events (deaths) per the protocol will occur by the end of 2023 or early 2024 and the final analysis after 80 events will occur by the end of 2024. Because these analyses are event driven, they may occur at a different time than currently expected.

In December 2020, we entered into an exclusive license agreement, or 3DMed License Agreement, with 3D Medicines Inc., or 3D Medicines, a China-based biopharmaceutical company developing next-generation immuno-oncology drugs, for the development and commercialization of GPS, as well as the Company’s next generation heptavalent immunotherapeutic GPS+, which is at preclinical stage, across all therapeutic and diagnostic uses in mainland China, Hong Kong, Macau and Taiwan, which we refer to as Greater China. We have retained sole rights to GPS and GPS+ outside of Greater China. In November 2022, we announced that we have agreed with 3D Medicines for 3D Medicines to participate in the REGAL study through the inclusion of approximately 20 patients from mainland China. Such participation by 3D Medicines will trigger two development milestone payments totaling $13.0 million, which we expect to receive in the first half of 2023. If the REGAL study meets its primary endpoint for efficacy and the Chinese regulatory authorities determine that the REGAL data is sufficient for approval in China, GPS could potentially reach the market in Greater China much earlier than we and 3D Medicines had anticipated when we entered into the license agreement in December 2020. As of March 15, 2023, we have received an aggregate of $10.5 million in upfront and milestone payments under our license agreement with 3D Medicines and a total of $191.5 million in potential future development, regulatory and sales milestones, not including future royalties, remains under the license agreement, which milestones are variable in nature and not under our control.

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In December 2018, pursuant to a Clinical Trial Collaboration and Supply Agreement, we initiated a Phase 1/2 multi-arm "basket" type clinical study of GPS in combination with Merck & Co., Inc.’s anti-PD-1 therapy, pembrolizumab (Keytruda). In 2020, we, together with Merck, determined to focus on ovarian cancer (second or third line). In November 2022, we reported topline clinical and initial immune response data from this study, which showed that treatment with the combination of GPS and pembrolizumab compared favorably to treatment with anti-PD-1 therapy alone in a similar patient population. We plan to present final data from this study at a medical conference in the first half of 2023.

In February 2020, a Phase 1 open-label investigator-sponsored clinical trial of GPS, in combination with Bristol-Myers Squibb’s anti-PD-1 therapy, nivolumab (Opdivo), in patients with malignant pleural mesothelioma, or MPM, who harbor relapsed or refractory disease after having received frontline standard of care multimodality therapy was commenced at MSK. Enrollment of a target total of 10 evaluable patients was completed at the end of 2022. We expect to report topline data from this study in the first half of 2023.

GPS was granted Orphan Drug Product Designations from the FDA, as well as Orphan Medicinal Product Designations from the European Medicines Agency, or EMA, for GPS in AML, MPM, and multiple myeloma, or MM, as well as Fast Track Designation for AML, MPM, and MM from the FDA.

GFH009: Highly Selective Next Generation CDK9 Inhibitor

On March 31, 2022, we entered into an exclusive license agreement, or the GFH009 Agreement, with GenFleet Therapeutics (Shanghai), Inc., or GenFleet, a clinical-stage biotechnology company developing cutting-edge therapeutics in oncology and immunology, that grants rights to us for the development and commercialization of GFH009, a highly selective small molecule CDK9 inhibitor, across all therapeutic and diagnostic uses worldwide, except for Greater China.

CDK9 activity has been shown to correlate negatively with overall survival in a number of cancer types, including hematologic cancers, such as AML and lymphomas, as well as solid cancers, such as osteosarcoma, pediatric soft tissue sarcomas, melanoma, endometrial, lung, prostate, breast and ovarian. As demonstrated in preclinical and clinical data, to date, GFH009’s high selectivity has the potential to reduce toxicity as compared to older CDK9 inhibitors and other next-generation CDK9 inhibitors currently in clinical development and to potentially be more efficacious.

GFH009 is currently in a Phase 1 dose-escalating clinical trial in the United States and China. We are evaluating both twice-a-week and once-a-week dosing, and the indications are relapsed/refractory AML, chronic lymphocytic leukemia, or CLL, small lymphocytic leukemia, or SLL, and lymphoma. The primary goal of the trial is to establish the recommended Phase 2 dose and to assess safety. We expect enrollment in this study to be completed in the first quarter of 2023 and we expect to determine the recommended Phase 2 dose and report analyzed data from the study early in the second quarter of 2023.

Following completion of the Phase 1 clinical trial and determination of the recommended Phase 2 dose, we intend to commence a Phase 2a clinical trial of GFH009 in combination with venetoclax and azacitidine in AML patients who failed or did not respond to treatment with venetoclax and azacitidine. The primary endpoint of the Phase 2a clinical trial, which we expect to initiate during the second quarter of 2023, will likely be complete remission, or CR, rate and secondary endpoints will likely include progression free survival, OS and proportion of patients proceeding to transplant. We are also planning to potentially commence a Phase 2 clinical trial of GFH009 in certain solid tumors and/or lymphoma in the third quarter of 2023 and are exploring various options with respect to clinical development for GFH009 in several pediatric indications.

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Impact of COVID-19

Public health crises such as pandemics or similar outbreaks could adversely impact our business. Notably, the COVID-19 pandemic continues to evolve. The extent to which COVID-19 impacts our operations or those of our collaborators, contractors, suppliers, CROs, clinical sites, CMOs and other material business relations and governmental agencies will depend on future developments, which are highly uncertain and cannot be predicted with confidence, including the ultimate duration of the outbreak, new information that will emerge concerning the severity of the virus and the actions to contain it or treat its impact, among others. Previously, our clinical trial operations were directly and indirectly adversely impacted, and could continue to be directly and indirectly adversely impacted, by the COVID-19 pandemic. While the potential economic impact brought by, and the ultimate duration of, the COVID-19 pandemic, have been, and continue to be, difficult to assess or predict, the spread of COVID-19 has caused a broad impact globally. The extent to which the COVID-19 pandemic may impact our business continues to be highly uncertain and cannot be predicted with confidence.

Components of Results of Operations

License Revenue

License revenue consists of revenue recognized pursuant to the 3DMed License Agreement. In the future, we may generate revenue from a combination of regulatory, development, and sales milestone payments and royalties in connection with the 3DMed License Agreement.

Research and Development

Research and development expense consists of expenses incurred in connection with the discovery and development of our product candidates. We expense research and development costs as incurred. These expenses include:

•expenses incurred under agreements with CROs, as well as investigative sites and consultants that conduct our preclinical studies and clinical trials;

•manufacturing and clinical drug supply expenses;

•outsourced professional scientific development services;

•employee-related expenses, which include salaries, benefits and stock-based compensation;

•payments made under our license agreements, under which we acquired certain intellectual property;

•expenses relating to certain regulatory activities, including filing fees paid to regulatory agencies;

•laboratory materials and supplies used to support our research activities; and

•allocated expenses, utilities and other facility-related costs.

The successful development of our current and future product candidates is highly uncertain. At this time, we cannot reasonably estimate or know the nature, timing and costs of the efforts that will be necessary to complete the remainder of the development of, or when, if ever, material net cash inflows may commence from, any current or future product candidates. This uncertainty is due to the numerous risks and uncertainties associated with the duration and cost of our clinical trials, which vary significantly over the life of a project as a result of many factors, including:

•the number and geographical location of clinical sites included in the trials;

•the length of time required to enroll suitable patients;

•the number and geographical location of patients that ultimately participate in the trials;

•the number of doses patients receive;

•the duration of patient follow-up;

•the results of clinical trials;

•the expenses associated with manufacturing and clinical drug supply;

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•the receipt of marketing approvals; and

•the commercialization of current and future product candidates.

Research and development activities are central to our business model. Oncology product candidates in the later stages of clinical development generally have higher development costs than those in the earlier stages of clinical development, primarily due to the increased size and duration of the later-stage clinical trials. We expect our research and development expenses to increase for the foreseeable future as we conduct and complete our ongoing early and late-stage clinical trials and initiate additional clinical trials.

Our expenditures are subject to additional uncertainties, including the terms and timing of regulatory approvals. We may never succeed in achieving regulatory approval for any of our current or future product candidates. We may obtain unexpected results from our clinical trials. We may elect to discontinue, delay or modify clinical trials of some product candidates or target indications or focus on others. A change in the outcome of any of these variables with respect to the development of a product candidate could mean a significant change in the costs and timing associated with the development of that product candidate. For example, if the FDA or other regulatory authorities were to require us to conduct clinical trials beyond those that we currently anticipate, or if we experience significant delays in enrollment in any of our clinical trials, we could be required to expend significant additional financial resources and time on the completion of clinical development.

General and Administrative Expense

General and administrative expenses consist principally of salaries and related costs for personnel in executive, administrative, finance and legal functions, including stock-based compensation, travel expenses and recruiting expenses, fees for outside legal counsel, and director and officer insurance premiums. Other general and administrative expenses include facility related costs, patent filing and prosecution costs, professional fees for business development, accounting, consulting, legal and tax-related services associated with maintaining compliance with our Nasdaq listing and SEC reporting requirements, investor relations costs, and other expenses associated with being a public company.

If and when we believe that regulatory approval of a product candidate appears likely, we anticipate that an increase in general and administrative expenses will occur as a result of our preparation for commercial operations, particularly as it relates to the sales and marketing of such product candidate. Oncology product commercialization may take several years and millions of dollars in development costs.

Acquired In-Process Research and Development

Acquired in-process research and development consists of costs to acquire or license product candidates from third parties for development with no alternative future use as the technology and know-how acquired are not currently commercially viable.

In-Process Research and Development Impairment Charge

Intangible assets are comprised of identifiable in-process research and development assets, or IPR&D, and are considered indefinite-lived assets and are assessed for impairment annually or more frequently if impairment indicators are present. Our indefinite-lived intangible asset consisted of IPR&D of nelipepimut-S, or NPS, that was acquired as part of the merger with Galena Biopharma, Inc. in 2017, or the Merger. We are not currently engaging in any clinical development activities for NPS nor do we currently have any plans to do so in the future. The impairment charge recognized during the year ended December 31, 2021 was a result of the determination that the carrying amount of the IPR&D was not recoverable and was measured by the amount the carrying value exceeded its fair value.

Non-Operating Income

Non-operating income consists of changes in fair value of our warrant liability, changes in fair value of our contingent consideration, and interest income. Interest income primarily reflects the interest earned from our cash and cash equivalents.

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Results of Operations for the Years Ended December 31, 2022 and 2021

The following table summarizes our results of operations for the years ended December 31, 2022 and 2021 (amounts in thousands):

Year ended December 31,

Operating expenses:

Acquired in-process research and development 10,000 — 10,000

In-process research and development charge — 5,700 (5,700)

For the year ended December 31, 2022, our net loss was $41.3 million compared with a net loss of $20.7 million for the year ended December 31, 2021. The increase of $20.6 million in net loss was primarily attributable to an increase in operating expenses of $10.1 million, a decrease in licensing revenue of $6.6 million, a decrease of $3.7 million in non-operating income, and a $0.2 million decrease in income tax benefit. The increase in operating expenses were driven by a $10.0 million charge for acquired in-process research and development, a $4.6 million increase in research and development expenses, and a $1.3 million increase in general and administrative expenses, which were partially offset by a $5.7 million decrease in non-cash IPR&D impairment charges and a $0.1 million decrease in costs of license revenue.

Further analysis of the changes and trends in our operating results are discussed below.

License Revenue

License revenue for the year ended December 31, 2022 was $1.0 million and related to approval by China's NMPA of an IND application filed by 3D Medicines for a small Phase 1 clinical trial investigating safety of GPS in China. License revenue of $7.6 million for the year ended December 31, 2021 related to the out-licensing of intellectual property rights and transfer of technical know-how associated with the 3DMed License Agreement for the development and commercialization of GPS in Greater China.

Cost of License Revenue

We incurred $0.1 million and $0.2 million of sublicensing fees payable under our license from MSK in connection with the 3DMed License Agreement during the years ended December 31, 2022 and 2021, respectively.

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Research and Development

Research and development expenses were $20.3 million for the year ended December 31, 2022 compared to $15.7 million for the year ended December 31, 2021. As compared to the prior period, the $4.6 million increase in research and development expenses was primarily attributable to a $2.6 million increase in clinical trial expenses primarily related to our ongoing Phase 3 REGAL clinical trial of GPS in AML, a $1.4 million increase in personnel related expenses due to increased headcount, a $0.8 million increase in clinical and regulatory consulting expenses, and a $0.2 million increase in other research and development expenses. These increases were partially offset by a $0.4 million decrease in manufacturing and clinical drug supply costs due to the timing of registration batches and a technology transfer in the prior period. We anticipate that our research and development expenses will increase in the future as we continue to advance the development of GPS, including our Phase 3 REGAL clinical trial of GPS in AML, and the ongoing and planned clinical trials of GFH009.

General and Administrative

General and administrative expenses were $12.6 million for the year ended December 31, 2022 compared to $11.3 million for the year ended December 31, 2021. The $1.3 million increase was primarily driven by a $1.9 million increase in personnel related expenses due to increased headcount including a $0.6 million increase in non-cash stock-based compensation, a $0.7 million increase in outside services and public company costs, and a $0.2 million increase in office and other general and administrative costs. These increases were partially offset by a $1.1 million decrease related to amortization expense of our contract asset associated with the 3DMed License Agreement, and a $0.4 million decrease in legal fees.

Acquired In-Process Research and Development

During the year ended December 31, 2022, we recognized $10.0 million for the acquisition of in-process research and development related to the in-licensing of GFH009, a highly selective next generation CDK9 inhibitor, $4.5 million of which was paid in April 2022 and the remaining $5.5 million which is deemed probable to occur and expected to be paid by the end of the second quarter of 2023. There was no acquired in-process research and development expense during the year ended December 31, 2021.

In-Process Research and Development Impairment Charge

There were no in-process research and development charges during the year ended December 31, 2022. In the fourth quarter of 2021, we performed an annual impairment analysis of our IPR&D. The impairment charge recognized during the year ended December 31, 2021 was in connection with our determination that consummating an out-licensing transaction of NPS for further development in breast cancer was unlikely and taking into account the deferred development timelines and a lower probability of success associated with earlier stages of clinical development for the potential development of NPS in other oncology indications. The Company determined that the carrying amount of the IPR&D associated with NPS exceeded the fair value and recorded a $5.7 million impairment charge during the year ended December 31, 2021.

Non-Operating Income

Non-operating income for the years ended December 31, 2022 and 2021, respectively, was as follows (in thousands):

Year ended December 31,

Change in fair value of warrant liability $ 36 $ 15 $ 21

Change in fair value of contingent consideration 296 4,337 (4,041)

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The decrease in our non-operating income during the year ended December 31, 2022 compared to the year ended December 31, 2021 was primarily due to a $4.0 million decrease in the change in fair value of contingent consideration, partially offset by a $0.3 million increase in interest income earned from our cash and cash equivalents.

The $4.3 million change in estimated fair value of the contingent consideration during the year ended December 31, 2021 related to the inability to execute an out-licensing transaction of NPS for further development in breast cancer and reflected adjusted assumptions of deferred development timelines and a lower probability of success, associated with earlier stages of clinical development, for the potential development of NPS in other oncology indications. During the year ended December 31, 2022, we ceased all development activity of NPS and effort to out-license the asset in any indication and reduced the probability of success of achieving certain regulatory and net sales milestones to zero.

Interest income for the years ended December 31, 2022 and 2021 consists of interest earned from our cash and cash equivalents. Interest income increased during the year December 31, 2022 primarily due to higher interest rates. The change in estimated fair value of liability-classified warrants to acquire shares of our common stock during the years ended December 31, 2022 and 2021 related to changes in our common stock price and less time to expiration.

The changes in fair value of warrant liability and changes in fair value of contingent consideration are all non-cash in nature.

Income Tax Benefit

There was no income tax benefit recognized for the year ended December 31, 2022. For the year ended December 31, 2021, we recognized an income tax benefit of $0.2 million, primarily related to the intangible asset impairment charge.

Liquidity and Capital Resources

We did not generate any revenue from product sales in the years ended December 31, 2022 and 2021. Through December 31, 2022, we have only generated licensing revenue from the 3DMed License Agreement. Since inception, we have incurred net losses, used net cash in our operations, and have funded substantially all of our operations through proceeds of the sale of equity securities and convertible notes.

Sources of Liquidity

To date, we have received $10.5 million in upfront payments and certain technology transfer and regulatory milestones from 3DMed, pursuant to its Exclusive License Agreement for GPS. The participation of 3DMed in the REGAL Phase 3 clinical trial in China will trigger two development milestone payments totaling $13.0 million to us, which we expect to receive in the first half of 2023. A total of $191.5 million in potential future development, regulatory, and sales milestones, not including future royalties, remains under the 3DMed License Agreement as of December 31, 2022, which milestones are all variable in nature and not under the Company's control.

On February 28, 2023, we consummated an underwritten public offering, or the February 2023 Offering, issuing 7,220,217 shares of common stock and accompanying common stock warrants to purchase an aggregate of 7,220,217 shares of common stock. The shares of common stock and accompanying common stock warrants were sold at a combined price of $2.77 per share and accompanying common stock warrant. Each common stock warrant sold with the shares of common stock represents the right to purchase one share of our common stock at an exercise price of $2.77 per share. The common stock warrants are exercisable immediately and will expire on February 28, 2028, five years from the date of issuance. The net proceeds from the February 2023 Offering were approximately $18.5 million, after deducting underwriting discounts and commissions and estimated offering expenses, and excluding the exercise of any warrants.

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On April 5, 2022, we consummated an underwritten public offering, or the April 2022 Offering, issuing 4,629,630 shares of common stock and accompanying common stock warrants to purchase an aggregate of 4,629,630 shares of common stock. The shares of common stock and accompanying common stock warrants were sold at a combined price of $5.40 per share and accompanying common stock warrant. Each common stock warrant sold with the shares of common stock represents the right to purchase one share of our common stock at an exercise price of $5.40 per share. The common stock warrants are exercisable immediately and will expire on April 5, 2027, five years from the date of issuance. The net proceeds to us from the April 2022 Offering, after deducting the underwriting discounts and commissions and other offering expenses, and excluding the exercise of any warrants, were approximately $23.0 million.

On March 31, 2022, or the effective date of the GFH009 Agreement, we entered into the GFH009 Agreement with GenFleet pursuant to which GenFleet granted to us a sublicensable, royalty-bearing license to certain of its intellectual property to develop, manufacture, and commercialize GFH009 for the treatment, diagnosis or prevention of disease in humans and animals in all countries and territories of the world other than Greater China, or the GFH009 Territory. GFH009 is currently in a Phase 1 clinical trial in the United States and China. In consideration for the exclusive license, we agreed to pay GenFleet (i) an upfront and technology transfer fee of $10.0 million, of which $4.5 million was paid in April 2022, and $5.5 million is due upon the first day of the 15th calendar month following the effective date of the GFH009 Agreement, (ii) development and regulatory milestone payments for up to three indications totaling up to $48.0 million in the aggregate, and (iii) sales milestone payments totaling up to $92.0 million in the aggregate upon the achievement of certain net sales thresholds in a given calendar year. We have also agreed to pay GenFleet single-digit tiered royalties based upon a percentage of annual net sales, with the royalty rate escalating based on the level of annual net sales of GFH009 in the GFH009 Territory ranging from the low to high single digits.

On April 16, 2021, the Company entered into a Controlled Equity OfferingSM Sales Agreement, or the Sales Agreement, with Cantor Fitzgerald & Co., or the Agent. From time to time during the term of the Sales Agreement, we may offer and sell shares of common stock having an aggregate offering price up to a total of $50.0 million in gross proceeds. The Agent will collect a fee equal to 3% of the gross sales price of all shares of common stock sold. Shares of common stock sold under the Sales Agreement are offered and sold pursuant to our registration statement on Form S-3, which was filed with the SEC on April 16, 2021 and declared effective on April 29, 2021. During the year ended December 31, 2022, we sold 415,005 shares of common stock pursuant to the Sales Agreement at an average price of $2.60 per share for aggregate net proceeds of approximately $1.0 million. Subsequent to December 31, 2022, the Company sold 76,882 shares of common stock pursuant to the Sales Agreement at an average price of $3.59 for aggregate net proceeds of approximately $0.3 million. There remains approximately $39.2 million available for future sales of shares of common stock under the Sales Agreement. Other than the Sales Agreement, we currently do not have any commitments to obtain additional funds.

Funding Requirements

During the year ended December 31, 2022, we incurred a net loss of $41.3 million, used $23.8 million of cash in operations, and had an accumulated deficit of $179.9 million as of December 31, 2022. We continue to expect to generate operating losses and negative cash flows for the next few years and we will need additional funding to support our planned operating activities through profitability. The transition to profitability is dependent upon the successful development, approval, and commercialization of our product candidates and the achievement of a level of revenues adequate to support our cost structure. As of December 31, 2022, we had cash and cash equivalents of $17.1 million. We expect that our cash and cash equivalents will not be sufficient to fund our current planned operations for at least the next twelve months from the date of issuance of these financial statements. The $13.0 million of development milestone payments to us triggered by 3DMed's participation in the REGAL study are variable in nature and not under our control, and therefore are not included in our going concern assumption. These conditions give rise to a substantial doubt over our ability to continue as a going concern. This going concern assumption is based on management’s assessment of the sufficiency of our current and future sources of liquidity considering whether or not it is probable we will be able to meet our obligations as they become due for at least one year from the date our consolidated financial statements are available to be issued, and if not, whether our liquidation is imminent.

Our consolidated financial statements do not include any adjustments related to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty. We anticipate incurring additional losses until such time, if ever, that we can generate significant sales of any current or future product candidates in development.

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We will require substantial additional financing to develop any current or future product candidates. If we are unable to obtain additional funding on a timely basis, we will be required to scale back our plans and place certain activities on hold. Other than the Sales Agreement, we currently do not have any commitments to obtain additional funds. Our management continues to evaluate different strategies to obtain the required funding for future operations. These strategies may include utilizing the Sales Agreement, public and private placements of equity and/or debt securities and payments from potential strategic research and development collaborations. Additionally, we continue to pursue discussions with global and regional pharmaceutical companies for licensing and/or co-development rights to our product candidates. There can be no assurance that these future funding efforts will be successful.

Our future operations are highly dependent on a combination of factors, including (i) the timely and successful completion of any additional financings, (ii) our ability to complete revenue-generating partnerships with pharmaceutical and biotechnology companies, (iii) the success of our research and development activities, (iv) the development of competitive therapies by other biotechnology and pharmaceutical companies, and, ultimately, (v) regulatory approval and market acceptance of our product candidates.

Components of Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents

The following table provides a reconciliation of the components of cash, cash equivalents, restricted cash, and restricted cash equivalents reported in our consolidated balance sheets to the total of the amount presented in the consolidated statements of cash flows (in thousands):

December 31,

Restricted cash and cash equivalents 100 100

Restricted cash and cash equivalents of $0.1 million as of December 31, 2022 and 2021 related to certificates of deposit maintained on hand with our financial institutions as collateral for our corporate credit cards.

Cash Flows

The following table summarizes our cash flows from operating, investing, and financing activities for the years ended December 31, 2022 and 2021 (in thousands):

Year ended December 31,

Net cash (used in) provided by:

Investing activities (4,500) —

Net Cash Flow from Operating Activities

Net cash used in operating activities of $23.8 million during the year ended December 31, 2022 was primarily attributable to our net loss of $41.3 million, and partially offset by various net non-cash charges of $11.9 million, and a change in our operating assets and liabilities of $5.6 million. Net non-cash charges were driven by $10.0 million in expense related to the acquired in-process research and development, $1.7 million in non-cash stock compensation expense, and $0.2 million in other net non-cash charges. The net change in our operating assets and liabilities is due to an increase in accrued expenses and other current liabilities of $3.6 million, an increase in accounts payable of $1.2 million and a decrease in prepaid expenses and other current assets of $1.3 million, which was partially offset by a decrease in operating lease liabilities of $0.5 million.

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Net cash used in operating activities of $26.0 million during the year ended December 31, 2021 was primarily attributable to our net loss of $20.7 million and a change in our operating assets and liabilities of $7.6 million, which was partially offset by various net non-cash charges of $2.3 million. The net change in our operating assets and liabilities was primarily attributable to a decrease in deferred revenue of $5.6 million, a decrease in accounts payable and accrued expenses and other current liabilities of $1.8 million, a $1.1 million increase in prepaid expenses and other assets primarily for clinical trial costs, and a $0.2 million decrease in operating lease liabilities, which were partially offset by a $1.1 million decrease in contract acquisition costs related to the out-licensing of intellectual property rights and transfer of technical know-how associated with the 3DMed License Agreement.

Net Cash Used in Investing Activities

Net cash used in investing activities of $4.5 million during the year ended December 31, 2022 related to license payments made for the acquisition of in-process research and development under the GFH009 Agreement.

There was no cash used in investing activities during the year ended December 31, 2021.

Net Cash Flow from Financing Activities

We generated $24.1 million of net cash from financing activities for the year ended December 31, 2022, which was due to $23.0 million in aggregate net proceeds received from our underwritten public offering, which closed in April 2022, $1.0 million in aggregate net proceeds received from the issuance of common stock under the Sales Agreement, and $0.1 million in aggregate net proceeds received from the issuance of common stock under our employee stock purchase plan.

We generated $12.1 million of net cash from financing activities for the year ended December 31, 2021, which was primarily attributable to $9.0 million in net proceeds from the issuance of common stock under the Sales Agreement and $3.1 million in net proceeds from the exercise of warrants to acquire shares of common stock.

Contractual Obligations and Other Commitments

Leases

Our lease commitments reflect payments due under our lease agreement for our office space in New York, New York that expires in December 2024, including additional space which began in February 2022. As of December 31, 2022, our contractual commitment for our lease was $1.1 million, which will be paid over the remaining term of the lease. For additional information on our leases and timing of future payments, please read Note 8, Leases, to the consolidated financial statements included in this Form 10-K.

Other Commitments

We acquire product candidates still in development and enter into research and development arrangements with third parties that often require milestone and royalty payments to the third-party contingent upon the occurrence of certain future events linked to the success of the product candidate in development. Milestone payments may be required, contingent upon the successful achievement of an important point in the development life-cycle of the pharmaceutical product (e.g., approval of the product for marketing by a regulatory agency). We also typically will need to make royalty payments based upon a percentage of the sales of the product candidate in the event that regulatory approval for marketing is obtained. Because of the contingent nature of these payments, they are not included in the table of contractual obligations.

These arrangements may be material individually and, in the event that multiple milestones are reached in the same period, the aggregate charge to expense could be material to the results of operations in any one period. In addition, these arrangements often give us the discretion to terminate development of the product candidate, which would allow us to avoid making the contingent payments; however, we are unlikely to cease development if the product candidate successfully achieves clinical testing objectives.

We enter into contracts in the normal course of business with various third parties for clinical trials, manufacturing, and other services and products for operating purposes. These contracts provide for termination

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upon notice. Payments due upon cancellation generally consist only of payments for services provided or expenses incurred, including non-cancellable obligations of our service providers, up to the date of cancellation. These payments have not been included separately within these contractual and other obligations disclosures.

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Critical Accounting Policies and Estimates

Our consolidated financial statements are prepared in accordance with U.S. generally accepted accounting principles. The preparation of our consolidated financial statements and related disclosures requires our management to make estimates and judgments that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of revenues and expenses during the reported period. We base such estimates on historical experience, known trends and events and various other factors that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. We evaluate our estimates and assumptions on an ongoing basis. Our actual results may differ from these estimates under different assumptions and conditions.

While our significant accounting policies are described in more detail in the notes to our audited consolidated financial statements appearing elsewhere in this annual report on Form 10-K, we believe that the following accounting policies are those most critical to the judgments and estimates used in the preparation of our consolidated financial statements.

Revenue Recognition

We record revenue in accordance with Accounting Standard Codification, or ASC, Topic 606, Revenue From Contracts with Customers. This standard applies to all contracts with customers, except for contracts that are within the scope of other standards, such as leases, insurance, collaboration arrangements and financial instruments. Under Topic 606, an entity recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of Topic 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. We only apply the five-step model to contracts when it is probable that we will collect the consideration we are entitled to in exchange for the goods or services we transfer to the customer. At contract inception, once the contract is determined to be within the scope of Topic 606, we assess the goods or services promised within each contract and determine those that are performance obligations, and we assess whether each promised good or service is distinct. We then recognize as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied.

Development, Regulatory and Sales Milestones and Other Payments

At the inception of each arrangement that includes regulatory or development milestone payments, we evaluate whether the milestones are considered probable of being achieved and estimate the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of us or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. We evaluate factors such as the scientific, clinical, regulatory, commercial, and other risks that must be overcome to achieve the particular milestone in making this assessment. There is considerable judgment involved in determining whether it is probable that a significant revenue reversal would not occur. At the end of each subsequent reporting period, we reevaluate the probability of achievement of all milestones subject to constraint and, if necessary, adjust our estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment.

For arrangements that include sales-based royalties, including milestone payments upon first commercial sales and milestone payments based on a level of sales, which are the result of a customer-vendor relationship and for which the license is deemed to be the predominant item to which the royalties relate, we recognize revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied or partially satisfied. To date, we have not recognized any royalty revenue resulting from any of our licensing arrangements.

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Goodwill

Goodwill is the excess of the cost of an acquired entity over the net amounts assigned to tangible and intangible assets acquired and liabilities assumed. Goodwill is not amortized but is subject to an annual impairment test. We have a single reporting unit and all goodwill relates to that reporting unit.

We perform our annual goodwill impairment test at the reporting unit level on October 1 of each fiscal year or more frequently if changes in circumstances or the occurrence of events suggest that an impairment exists. Goodwill is evaluated for impairment using the simplified test of goodwill impairment as defined by the Financial Accounting Standards Board, or FASB, Accounting Standards Update, or ASU, No. 2017-04. Under the guidance, goodwill impairment is measured by the amount by which the carrying value of a reporting unit exceeds its fair value, without exceeding the carrying amount of goodwill allocated to that reporting unit. If the fair value of the reporting unit is less than its carrying value, an impairment loss is recorded to the extent that the implied fair value of the reporting unit’s goodwill is less than the carrying value of the reporting unit’s goodwill. We did not recognize any impairment of goodwill during the years ended December 31, 2022 and 2021.

Accrued Research and Development Expenses

As part of the process of preparing our consolidated financial statements, we are required to estimate our accrued research and development expenses. This process involves reviewing open contracts and purchase orders, communicating with applicable personnel to identify services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of actual costs. The majority of our service providers require advance payments; however, some invoice us in arrears for services performed, on a pre-determined schedule or when contractual milestones are met. We make estimates of our accrued expenses as of each balance sheet date in the consolidated financial statements based on facts and circumstances known to us at that time. We periodically confirm the accuracy of the estimates with the service providers and make adjustments if necessary. Examples of estimated accrued research and development expenses include fees paid to:

•Vendors in connection with clinical development activities;

•the production of clinical trial materials;

•CROs in connection with clinical trials; and

•investigative sites in connection with clinical trials.

We base our expenses related to clinical trials on our estimates of the services received and efforts expended pursuant to quotes and contracts with multiple research institutions and CROs that conduct and manage preclinical studies and clinical trials on our behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. There may be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the expense. Payments under some of these contracts depend on factors such as the successful enrollment of patients and the completion of clinical trial milestones. In accruing service fees, we estimate the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from the estimate, we adjust the accrual or prepaid accordingly. Although we do not expect its estimates to be materially different from amounts actually incurred, our understanding of the status and timing of services performed relative to the actual status and timing of services performed may vary and may result in reporting amounts that are too high or too low in any particular period. To date, we have not made any material adjustments to our prior estimates of accrued research and development expenses.

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Valuation of Contingent Consideration

Acquisitions may include contingent consideration payments based on the achievement of certain future events. Contingent consideration is required to be recognized at fair value as of the acquisition date. The obligations for such contingent consideration payments are recorded at fair value on the acquisition date. The contingent consideration obligations are then evaluated each reporting period. Changes in the fair value of contingent consideration, other than changes due to payments, are recognized as a gain or loss and recorded within the change in the fair value of contingent consideration in the consolidated statements of operations. The fair value of development and regulatory milestones are estimated utilizing a probability adjusted, discounted cash flow approach. The fair value of net sales milestones is based on probability adjusted sales estimates and estimated discount rates and utilizes an option pricing model with Monte Carlo simulation to simulate a range of possible payment scenarios, and the average of the payments in these scenarios is then discounted to calculate present fair value.

The discount rates are an estimated measure of credit risk associated with the years of expected payments based on the current development stage of the product candidate, our specific development plan for that product candidate adjusted for the probability of completing the stages of development and when the contingent payments would be triggered. In estimating the probability of success, we utilize data regarding similar milestone events from several sources, including industry studies and the Company's experience. The fair value of the contingent consideration is classified as a Level 3 liability as the valuation requires substantial judgment and estimation of factors that are not currently observable in the market. If different assumptions were used for the various inputs to the valuation, including but not limited to, assumptions involving the probability of success, estimated discount rate, and projected years of payment, the estimated fair value could be significantly higher or lower than the fair value determined.

Stock-Based Compensation

We account for stock-based compensation by estimating the fair value of each stock option on the date of grant using the Black-Scholes model. We recognize stock-based compensation expense on a straight-line basis over the vesting term. The Black-Scholes model requires us to make certain assumptions regarding: (i) the expected volatility in the market price of our shares; (ii) dividend yield; (iii) risk-free interest rates; and (iv) the period of time employees are expected to hold the award prior to exercise (referred to as the expected holding period). As a result, if we revise our assumptions and estimates, our stock-based compensation expense could change.

Given our limited history as a publicly traded company following the Merger on December 29, 2017, we did not have sufficient trading data to calculate volatility based on our own common stock, and the expected volatility was calculated as of each grant date based on our own implied volatility in combination with a peer group of publicly traded companies. The expected term of the stock options was determined based upon the simplified approach for employees and non-employee directors, allowed under SEC Staff Accounting Bulletin No. 110, which assumes that the stock options will be exercised evenly from vesting to expiration. As data associated with future exercises is obtained, the expected term of future grants will be adjusted accordingly.

We measure compensation for restricted stock units, or RSUs, based on the price of our shares at the grant date and we recognize the expense on a straight-line basis over the vesting period. The expense relating to RSUs that contain both a service and a performance condition is estimated and adjusted on a quarterly basis based upon our assessment of the probability that the performance condition would be met. As a result, if we revise such assessment, our stock-based compensation expense could change.

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ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

The primary objective of our investment activities is to preserve capital. We do not utilize hedging contracts or similar instruments.

We are exposed to certain market risks relating primarily to interest rate risk on our cash and cash equivalents and risks relating to the financial viability of the institutions which hold our capital and through which we have invested our funds. We manage such risks by investing primarily in money market mutual funds.

In addition, we are exposed to foreign currency exchange rate fluctuations relating to payments we make to certain vendors and suppliers and license partners using foreign currencies. We do not hedge against foreign currency risks. Consequently, changes in exchange rates could adversely affect our operating results and stock price. Such losses have not been significant to date.

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ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

Page

Notes to Consolidated Financial Statements 126

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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Stockholders and the Board of Directors of

SELLAS Life Sciences Group, Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of SELLAS Life Sciences Group, Inc. (the “Company”) as of December 31, 2022 and 2021, the related consolidated statements of operations, stockholders’ equity and cash flows for the years then ended, and the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the consolidated financial position of the Company as of December 31, 2022 and 2021, and the consolidated results of its operations and its cash flows for the years then ended, in conformity with accounting principles generally accepted in the United States of America.

Going Concern Uncertainty

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.

Basis for Opinion

These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s 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 consolidatedfinancial statements, whether due to error or fraud, and performing procedures to respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidatedfinancial 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

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.

/s/ Moss Adams LLP

Campbell, California

March 16, 2023

We have served as the Company’s auditor since 2018.

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SELLAS LIFE SCIENCES GROUP, INC.

CONSOLIDATED BALANCE SHEETS

(Amounts in thousands, except share and per share data)

December 31,

ASSETS

Current assets:

Restricted cash and cash equivalents 100 100

Prepaid expenses and other current assets 531 1,589

Operating lease right-of-use assets 874 723

Deposits and other assets 399 594

LIABILITIES AND STOCKHOLDERS’ EQUITY

Current liabilities:

Accrued expenses and other current liabilities 6,286 2,640

Operating lease liabilities 372 198

Acquired in-process research and development payable 5,500 —

Operating lease liabilities, non-current 573 610

Warrant liability 4 40

Contingent consideration — 296

Commitments and contingencies (Note 8)

Stockholders’ equity:

Total liabilities and stockholders’ equity $ 20,943 $ 26,275

See accompanying notes to these consolidated financial statements.

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SELLAS LIFE SCIENCES GROUP, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS

(Amounts in thousands, except share and per share data)

Year Ended December 31,

Operating expenses:

Acquired in-process research and development 10,000 —

In-process research and development impairment charge — 5,700

Non-operating income:

Change in fair value of warrant liability 36 15

Change in fair value of contingent consideration 296 4,337

Interest income 317 6

Total non-operating income 649 4,358

Income tax benefit — 237

Per share information:

Net loss per common share, basic and diluted $ (2.13) $ (1.34)

See accompanying notes to these consolidated financial statements.

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SELLAS LIFE SCIENCES GROUP, INC.

CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY

(Amounts in thousands, except share amounts)

Shares Amount

Issuance of common stock, net of issuance costs 786,927 — 9,005 — 9,005

Vesting of restricted stock units 10,095 — — — —

Stock-based compensation — — 1,011 — 1,011

Issuance of common stock, net of issuance costs 415,005 — 1,048 — 1,048

Issuance of common stock under employee stock purchase plan 25,089 — 85 — 85

Vesting of restricted stock units 40,044 — — — —

Stock-based compensation — — 1,726 — 1,726

See accompanying notes to these consolidated financial statements.

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SELLAS LIFE SCIENCES GROUP, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS

(Amounts in thousands)

Year ended December 31,

Cash flows from operating activities:

Adjustment to reconcile net loss to net cash used in operating activities:

Acquired in-process research and development charge 10,000 —

Non-cash in-process research and development impairment charge — 5,700

Non-cash stock-based compensation 1,726 1,011

Change in fair value of contingent consideration (296) (4,337)

Change in fair value of common stock warrants (36) (15)

Deferred income taxes — (239)

Changes in operating assets and liabilities:

Contract asset — 1,128

Prepaid expenses and other assets 1,253 (1,174)

Accrued expenses and other current liabilities 3,646 727

Operating lease liabilities (471) (183)

Deferred revenue — (5,600)

Net cash used in operating activities (23,809) (26,021)

Cash flows from investing activities:

Cash paid for acquisition of in-process research and development (4,500) —

Net cash used in investing activities (4,500) —

Cash flows from financing activities:

Proceeds from issuance of common stock, net of issuance costs 1,048 9,005

Proceeds from employee stock plan purchases 85 —

Proceeds from exercise of warrants — 3,069

Net cash provided by financing activities 24,079 12,074

Supplemental disclosure of cash flow information:

Cash received during the year for interest $ 317 $ 6

Supplemental disclosures:

Payable for acquired in-process research and development $ 5,500 $ —

See accompanying notes to these consolidated financial statements.

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SELLAS LIFE SCIENCES GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1. Organization and Description of Business

SELLAS Life Sciences Group, Inc. (the "Company" or "SELLAS") is a late-stage clinical biopharmaceutical company focused on novel therapeutics for a broad range of cancer indications. SELLAS’ lead product candidate, galinpepimut-S ("GPS"), is a cancer immunotherapeutic agent licensed from Memorial Sloan Kettering Cancer Center ("MSK") and targets the Wilms Tumor 1 ("WT1") protein, which is present in an array of tumor types. GPS has potential as a monotherapy or in combination with other immunotherapeutic agents to address a broad spectrum of hematologic, or blood, cancers and solid tumor indications. SELLAS' second product candidate is GFH009, a small molecule, highly selective cyclin-dependent kinase 9 ("CDK9") inhibitor, which is licensed from GenFleet Therapeutics (Shanghai), Inc. ("GenFleet"), for all therapeutic and diagnostic uses in the world outside of Greater China (mainland China, Hong Kong, Macau and Taiwan).

As used in this Annual Report on Form 10-K, the words the "Company," and "SELLAS" refer to SELLAS Life Sciences Group, Inc. and its consolidated subsidiaries following the completion of the business combination with Galena Biopharma, Inc., a Delaware corporation ("Galena"), and SELLAS Life Sciences Group, Ltd., a privately held Bermuda exempted company ("Private SELLAS") in December 2017. This business combination is referred to as the Merger. Upon completion of the Merger, the Company's name changed from "Galena Biopharma, Inc." to "SELLAS Life Sciences Group, Inc." and the Company's financial statements became those of Private SELLAS.

2. Liquidity and Going Concern

The accompanying consolidated financial statements have been prepared on a going concern basis, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business. The accompanying consolidated financial statements do not reflect any adjustments relating to the recoverability and reclassifications of assets and liabilities that might be necessary if the Company is unable to continue as a going concern. The Company expects its costs and expenses to increase as it continues to develop its product candidates and progress its current and planned clinical programs.

Pursuant to the requirements of Accounting Standard Codification ("ASC") 205-40, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern, management must evaluate whether there are conditions or events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the consolidated financial statements are issued. This evaluation initially does not take into consideration the potential mitigating effect of management’s plans that have not been fully implemented as of the date these financial statements are issued, but will consider such plans if (1) it is probable that the plans will be effectively implemented within one year after the date the financial statements are issued, and (2) it is probable that the plans, when implemented, will mitigate the relevant condition or events that raise substantial doubt about the entity’s ability to continue as a going concern within one year after the date the consolidated financial statements are issued. Certain elements of the Company’s operating plan to alleviate the conditions that raise substantial doubt are outside of the Company’s control and cannot be included in management’s evaluation under the requirements of ASC 205-40.

Since inception, the Company has incurred recurring losses and negative cash flows from operations and has an accumulated deficit of $179.9 million as of December 31, 2022. During the year ended December 31, 2022, the Company incurred a net loss of $41.3 million and used $23.8 million of cash in operations. The Company continues to expect to generate operating losses and negative cash flows for the next few years and will need additional funding to support its planned operating activities through profitability. The transition to profitability is dependent upon the successful development, approval, and commercialization of the Company's product candidates and the achievement of a level of revenues adequate to support its cost structure. As of December 31, 2022, the Company had cash and cash equivalents of $17.1 million. The Company expects its cash and cash equivalents will not be sufficient to fund its current planned operations for at least the next twelve months from the date of issuance of these financial statements. The $13.0 million of development milestone payments to the Company triggered by 3DMed's participation in the REGAL study are variable in nature and not under the Company's control, and therefore are not included in the Company's going concern assumption. These conditions give rise to a substantial doubt over the Company’s ability to continue as a going concern. These consolidated financial statements do not include any adjustments related to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty.

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SELLAS LIFE SCIENCES GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS - Continued

On February 28, 2023, the Company consummated an underwritten public offering (the "February 2023 Offering"), issuing 7,220,217 shares of common stock and accompanying common stock warrants to purchase an aggregate of 7,220,217 shares of common stock. The shares of common stock and accompanying common stock warrants were sold at a combined price of $2.77 per share and accompanying common stock warrant. Each common stock warrant sold with the shares of common stock represents the right to purchase one share of the Company’s common stock at an exercise price of $2.77 per share. The common stock warrants are exercisable immediately and will expire on February 28, 2028, five years from the date of issuance. The net proceeds to the Company from the February 2023 Offering were approximately $18.5 million, after deducting underwriting discounts and commissions and estimated offering expenses, and excluding the exercise of any warrants.

On April 16, 2021, the Company entered into a Controlled Equity OfferingSM Sales Agreement (the "Sales Agreement"), with Cantor Fitzgerald & Co. (the "Agent"). From time to time during the term of the Sales Agreement, the Company may offer and sell shares of common stock having an aggregate offering price up to a total of $50.0 million in gross proceeds. The Agent will collect a fee equal to 3% of the gross sales price of all shares of common stock sold. Shares of common stock sold under the Sales Agreement are offered and sold pursuant to the Company's registration statement on Form S-3, which was filed with the U.S. Securities and Exchange Commission ("SEC") on April 16, 2021 and declared effective on April 29, 2021. During the year ended December 31, 2022, the Company sold 415,005 shares of common stock pursuant to the Sales Agreement at an average price of $2.60 per share for aggregate net proceeds of approximately $1.0 million. Subsequent to December 31, 2022, the Company sold 76,882shares of common stock pursuant to the Sales Agreement at an average price of $3.59 for aggregate net proceeds of approximately $0.3 million. There remains approximately $39.2 million available for future sales of shares of common stock under the Sales Agreement. Other than the Sales Agreement, the Company currently does not have any commitments to obtain additional funds.

In December 2020, the Company, together with its wholly-owned subsidiary, SLSG Limited, LLC, entered into an Exclusive License Agreement (the “3DMed License Agreement”) with 3D Medicines Inc. ("3DMed"), pursuant to which the Company granted 3DMed a sublicensable, royalty-bearing license, under certain intellectual property owned or controlled by the Company, to develop, manufacture and have manufactured, and commercialize GPS and heptavalent GPS product candidates for all therapeutic and other diagnostic uses in mainland China, Hong Kong, Macau and Taiwan ("3DMed Territory"). To date, the Company has received $10.5 million in upfront payments and certain technology transfer and regulatory milestones. The participation of 3DMed in the Company's REGAL Phase 3 clinical trial in China will trigger two development milestone payments totaling $13.0 million to the Company, which the Company expects to receive in the first half of 2023. A total of $191.5 million in potential future development, regulatory, and sales milestones, not including future royalties, remains under the 3DMed License Agreement as of December 31, 2022, which milestones are all variable in nature and not under the Company's control.

The Company will require substantial additional financing to commercially develop any current or future product candidates. If the Company is unable to obtain additional funding on a timely basis, it will be required to scale back its plans and place certain activities on hold. Other than the Sales Agreement, the Company currently does not have any commitments to obtain additional funds. The Company's management continues to evaluate different strategies to obtain the required funding for future operations. These strategies may include utilizing the Sales Agreement, public and private placements of equity and/or debt securities and payments from potential strategic research and development collaborations. Additionally, the Company may pursue discussions with global and regional pharmaceutical companies for licensing and/or co-development rights to its product candidates. The Company has prepared its consolidated financial statements assuming that it will continue as a going concern, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business.

3. Basis of Presentation and Significant Accounting Policies

Basis of Presentation

The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to U.S. GAAP as found in the Accounting Standards Codification ("ASC") and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”).

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SELLAS LIFE SCIENCES GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS - Continued

Principles of Consolidation

The consolidated financial statements include the financial statements of the Company and its wholly owned subsidiaries. All significant intercompany accounts and transactions have been eliminated upon consolidation. Unless the context otherwise indicates, reference in these notes to the "Company" refer to SELLAS Life Sciences Group, Inc., and its wholly owned subsidiaries, Private SELLAS, SLSG Limited, LLC, Sellas Life Sciences Limited, and Apthera, Inc. The functional currency of the Company's non-U.S. operations is the U.S. dollar.

Use of Estimates

The preparation of these consolidated financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period.

On an ongoing basis, the Company evaluates its estimates using historical experience and other factors, including the current economic environment. Significant items subject to such estimates are assumptions used for purposes of determining stock-based compensation, carrying value of goodwill, accounting for deferred income taxes, and accounting for research and development activities. Management believes its estimates to be reasonable under the circumstances. Actual results could differ significantly from those estimates.

Segment Information

Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business in one segment.

Fair Value of Financial Instruments

The Company measures certain financial assets and liabilities at fair value on a recurring basis. Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. A three-tier fair value hierarchy is established as a basis for considering such assumptions and for inputs used in the valuation methodologies in measuring fair value:

Level 1—Quoted prices in active markets for identical assets or liabilities.

Level 2—Inputs other than quoted prices included within Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

As of December 31, 2022 and 2021, the carrying amounts of the Company’s financial instruments, including cash equivalents and accounts payable, approximate fair value due to the short-term nature of those instruments and were categorized as Level 1. As of December 31, 2022 and 2021, the carrying amounts of the Company’s contingent consideration and liability-classified warrants are each recorded at their estimated fair value.The fair value of the contingent consideration and warrants utilize certain unobservable inputs that fall within Level 3 of the fair value hierarchy. See Note 6 for additional information on the fair value of certain financial assets and liabilities.

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SELLAS LIFE SCIENCES GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS - Continued

Concentration of Credit Risk

Financial instruments that potentially expose the Company to concentrations of credit risk consist principally of cash on deposit with financial institutions, the balances of which frequently exceed federally insured limits. On March 10, 2023, Silicon Valley Bank ("SVB") was closed by the California Department of Financial Protection and Innovation, which appointed the Federal Deposit Insurance Corporation ("FDIC") as receiver.If any of the financial institutions with whom we do business were to be placed into receivership, we may be unable to access to the cash we have on deposit with such institutions.

Impact of COVID-19

Public health crises such as pandemics or similar outbreaks could adversely impact our business. Notably, the COVID-19 pandemic continues to evolve. The extent to which COVID-19 impacts our operations or those of our collaborators, contractors, suppliers, CROs, clinical sites, CMOs and other material business relations and governmental agencies will depend on future developments, which are highly uncertain and cannot be predicted with confidence, including the ultimate duration of the outbreak, new information that will emerge concerning the severity of the virus and the actions to contain it or treat its impact, among others. Previously, our clinical trial operations were directly and indirectly adversely impacted, and could continue to be directly and indirectly adversely impacted, by the COVID-19 pandemic. While the potential economic impact brought by, and the ultimate duration of, the COVID-19 pandemic, have been, and continue to be, difficult to assess or predict, the spread of COVID-19 has caused a broad impact globally. The extent to which the COVID-19 pandemic may impact our business continues to be highly uncertain and cannot be predicted with confidence.

Cash and Cash Equivalents

The Company considers any highly liquid investments, such as money market funds, with an original maturity of three months or less to be cash and cash equivalents.

Restricted Cash and Cash Equivalents

Restricted cash consists of certificates of deposit on hand with the Company’s financial institutions as collateral for its corporate credit cards.

The following table provides a reconciliation of the components of cash, cash equivalents, restricted cash, and restricted cash equivalents reported in the Company's consolidated balance sheets to the total amount presented in the consolidated statements of cash flows (in thousands):

December 31,

Restricted cash and cash equivalents 100 100

The Company maintained $0.1 million as of December 31, 2022 and 2021, on hand with the Company's financial institutions as collateral for its corporate credit cards.

Goodwill

Goodwill is the excess of the cost of an acquired entity over the net amounts assigned to tangible and intangible assets acquired and liabilities assumed. Goodwill is not amortized but is subject to an annual impairment test. The Company has a single reporting unit and all goodwill relates to that reporting unit. The Company performs its annual goodwill impairment test in the fourth quarter of each fiscal year or more frequently if changes in circumstances or the occurrence of events suggest that an impairment exists. The Company did not recognize any impairment of goodwill during the years ended December 31, 2022 and 2021.

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SELLAS LIFE SCIENCES GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS - Continued

Contingent Consideration

The consideration for Galena's acquisition of Apthera, Inc. in 2011 includes future payments that are contingent upon the achievement of certain events related to the development and commercialization of nelipepimut-S ("NPS"). Contingent consideration, and the obligations for such contingent consideration payments, is required to be recognized at fair value as of the acquisition date. The contingent consideration obligations are then evaluated each reporting period and changes in the fair value of contingent consideration, other than changes due to payments, are recognized as a gain or loss and recorded within the change in the fair value of contingent consideration in the Company's consolidated statements of operations. The fair value of development and regulatory milestones are estimated utilizing a probability adjusted, discounted cash flow approach. The fair value of net sales milestones is based on probability adjusted sales estimates and estimated discount rates and utilizes an option pricing model with Monte Carlo simulation to simulate a range of possible payment scenarios, and the average of the payments in these scenarios is then discounted to calculate present fair value.

The discount rates used are an estimated measure of credit risk associated with the years of expected payments based on the current development stage of the associated product candidate, the Company's specific development plan for that product candidate adjusted for the probability of completing the stages of development and when the contingent payments would be triggered. In estimating the probability of success, the Company utilizes data regarding similar milestone events from several sources, including industry studies and the Company's experience. The fair value of the contingent consideration is classified as a Level 3 liability as the valuation requires substantial judgment and estimation of factors that are not currently observable in the market. If different assumptions were used for the various inputs to the valuation, including but not limited to, assumptions involving the probability of success, estimated discount rate, and projected years of payment, the estimated fair value could be significantly higher or lower than the fair value determined. See Note 6 for additional information on the contingent consideration.

Leases

The Company accounts for its leasing arrangements under ASU No. 2016-02, Leases (Topic 842) (“Topic 842”). Under Topic 842, all significant lease arrangements are generally recognized at lease commencement. Operating lease right-of-use ("ROU"), assets and lease liabilities are recognized at the commencement date. An ROU asset and corresponding lease liability is not recorded for leases with an initial term of 12 months or less (short term leases) and the Company recognizes lease expense for these leases as incurred over the lease term.

ROU assets represent the Company’s right to use an underlying asset during the reasonably certain lease terms and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the option will be exercised. Operating lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. The Company primarily uses its incremental borrowing rate, based on the information available at commencement date, in determining the present value of lease payments. The operating lease ROU asset also includes any lease payments related to initial direct cost and prepayments and excludes lease incentives. Lease expense is recognized on a straight-line basis over the lease term. The Company’s lease agreements contain lease and non-lease components, which are generally accounted for separately. See Note 8 for discussion of the Company’s facility lease.

Revenue Recognition

The Company records revenue in accordance with ASC Topic 606, Revenue From Contracts with Customers ("Topic 606"). This standard applies to all contracts with customers, except for contracts that are within the scope of other standards, such as leases, insurance, collaboration arrangements and financial instruments. Under Topic 606, an entity recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of Topic 606, the entity performs the following five-steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance

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obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five step model to contracts when it is probable that the entity will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception, once the contract is determined to be within the scope of Topic 606, the Company assesses the goods or services promised within each contract and determines those that are performance obligations, and assesses whether each promised good or service is distinct. The Company then allocates the transaction price to each distinct performance obligation based on its relative standalone selling price. The Company recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. See Note 11 for further discussion of the Company's revenue recognition associated with the 3DMed License Agreement.

Development, Regulatory and Sales Milestones and Other Payments

At the inception of each arrangement that includes regulatory or development milestone payments, the Company evaluates whether the milestones are considered probable of being achieved and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. The Company evaluates factors such as the scientific, clinical, regulatory, commercial, and other risks that must be overcome to achieve the particular milestone in making this assessment. There is considerable judgment involved in determining whether it is probable that a significant revenue reversal would not occur. At the end of each subsequent reporting period, the Company reevaluates the probability of achievement of all milestones subject to constraint and, if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment.

For arrangements that include sales-based royalties, including milestone payments upon first commercial sales and milestone payments based on a level of sales, which are the result of a customer-vendor relationship and for which the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied or partially satisfied. To date, the Company has not recognized any royalty revenue resulting from any of its licensing arrangements.

Acquired In-Process Research and Development

Costs incurred in obtaining technology licenses are immediately recognized as acquired in-process research and development expense, provided the technology licensed has no alternative future use as the technology and know-how acquired are not currently commercially viable. Payments related to contingent consideration such as development milestones, commercial milestones and royalties (Note 8) will be recognized when the contingency is probable and reasonably estimable in accordance with ASC 450, Contingencies.

Research and Development Expenses

Research and development costs are expensed as incurred. Research and development costs that are paid in advance of performance are capitalized as a prepaid expense and recognized as research and development expenses as the services are provided. Clinical study costs, a component of research and development expenses, are accrued over the service periods specified in the contracts and adjusted as necessary based on an ongoing review of the level of effort and costs actually incurred.

Research and development expenses consist primarily of development research performed by contract research organizations ("CROs"), personnel costs, including salaries, benefits and stock-based compensation, clinical drug supply, investigator grants, materials and supplies, consulting fees, licenses and fees, preclinical studies, and overhead allocations consisting of various support and facility-related costs.

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Stock-based Compensation

The Company measures employee and non-employee director share-based awards at their grant-date fair value and records compensation expense on a straight-line basis over the vesting period of the awards.

Estimating the fair value of share-based awards requires the input of subjective assumptions, including the expected life of the options and stock price volatility. The Company accounts for forfeitures for stock option awards as they occur. The Company uses the Black-Scholes option pricing model to value its stock option awards. The assumptions used in estimating the fair value of share-based awards represent management’s estimate and involve inherent uncertainties and the application of management’s judgment. As a result, if factors change and management uses different assumptions, share-based compensation expense could be materially different for future awards.

The expected life of the stock options is estimated using the “simplified method,” as the Company has limited historical information from which to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior for its stock option grants. The simplified method is the midpoint between the vesting period and the contractual term of the option. The stock price volatility assumption is based on the historical volatility of the Company's publicly traded common stock. The risk-free rate is based on the U.S. Treasury yield curve commensurate with the expected life of the option.

Restricted Stock Units with Performance and Service Conditions

The Company's Board of Directors has granted restricted stock units ("RSUs") to certain employees that vest based on performance and service conditions. The fair values of the performance-based RSUs are measured on the date of grant and are based on the Company's closing stock price on such date. Compensation expense is recognized for the number of performance-based RSUs expected to be earned, provided the requisite service period has been rendered, after assessing the probability that certain performance criteria will be met. Cumulative adjustments are recorded each quarter to reflect the estimated outcome of the performance-related conditions until the date results are determined and settled. The Company accounts for forfeitures of performance-based RSUs when they occur. If performance criteria are not met or are not expected to be met, any compensation expense previously recognized to date associated with the performance-based RSUs will be reversed.

Restricted Stock Units with Service Conditions Only

The Board of Directors has granted RSUs to certain employees that vest based on continuous service. Time-vested RSUs awarded to employees vest one-fourth per year annually over four years, provided the employee remains employed with the Company. The fair values of the time-vested RSUs are measured on the date of grant and are based on the Company's closing stock price on such date. Compensation expense for time-vested RSUs with service conditions only are recognized straight-line over the applicable service period. The Company accounts for forfeitures of time-vested RSUs when they occur. Previously recognized compensation expense for forfeited RSUs are reversed in the period the time-vested RSUs are forfeited.

Income Taxes

The Company uses the asset and liability method of accounting for income taxes. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. The Company recognizes the benefit of an uncertain tax position that it has taken or expects to take on its income tax returns, if such a position is more likely than not to be sustained. Potential interest and penalties associated with unrecognized tax positions are recognized in income tax expense. No interest or penalties were recognized in either of the years ended December 31, 2022 or 2021.

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The Company recognizes liabilities or assets for the deferred tax consequences of temporary differences between the tax basis of assets or liabilities and their reported amounts in the consolidated financial statements in accordance with FASB ASC 740-10, “Accounting for Income Taxes” (“ASC 740-10”). These temporary differences will result in taxable or deductible amounts in future years when the reported amounts of the assets or liabilities are recovered or settled. ASC 740-10requires that a valuation allowance be established when management determines that it is more likely than not that all or a portion of a deferred asset will not be realized. The Company evaluates the realizability of its net deferred income tax assets and valuation allowances as necessary, at least on an annual basis. During this evaluation, the Company reviews its forecasts of income in conjunction with other positive and negative evidence surrounding the realizability of its deferred income tax assets to determine if a valuation allowance is required. Adjustments to the valuation allowance will increase or decrease the Company’s income tax provision or benefit. The recognition and measurement of benefits related to the Company’s tax positions requires significant judgment, as uncertainties often exist with respect to new laws, new interpretations of existing laws, and rulings by taxing authorities. Differences between actual results and the Company’s assumptions or changes in the Company’s assumptions in future periods are recorded in the period they become known.

Net Loss Per Share

Basic loss per share is computed by dividing net loss applicable to common stockholders by the weighted average number of shares of common stock outstanding during each period. Diluted loss per share includes the effect, if any, from the potential exercise or conversion of securities, such as warrants, stock options and unvested restricted stock that would result in the issuance of incremental shares of common stock. In computing the basic and diluted net loss per share, the weighted average number of shares remains the same for both calculations due to the fact that when a net loss exists, dilutive shares are not included in the calculation as the impact is anti-dilutive.

The following potentially dilutive securities outstanding have been excluded from the computation of diluted weighted average shares outstanding, as their impact would be anti-dilutive (in thousands):

December 31,

Recent Accounting Pronouncements Adopted

In May 2021, the FASB issued ASU No. 2021-04, Issuer’s Accounting for Certain Modifications of Exchanges of Freestanding Equity-Classified Written Call Options, to clarify the accounting for modifications or exchanges of freestanding equity-classified written call options, such as warrants, that remain equity classified after modification or exchange. This ASU became effective for the Company on January 1, 2022 and did not have a material impact on the Company's consolidated financial statements.

Recent Accounting Standards Not Yet Adopted

In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity, which, among other things, simplifies the accounting models for the allocation of proceeds attributable to the issuance of a convertible debt instrument. As a result, after adopting the ASU’s guidance, entities will not separately present in equity an embedded conversion feature in such debt. Instead, they will account for a convertible debt instrument wholly as debt, and for convertible preferred stock wholly as preferred stock (i.e., as a single unit of account), unless (i) a convertible instrument contains features that require bifurcation as a derivative under ASC 815 or (ii) a convertible debt instrument was issued at a substantial premium. The standard becomes effective for the Company in the first quarter of 2024 and

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early adoption is permitted. The Company is currently evaluating the potential impact of the adoption of this standard on its consolidated financial statements.

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4. Goodwill and Intangible Assets

A reconciliation of the change in goodwill and intangible assets for the years ended December 31, 2022 and 2021 is as follows (in thousands):

In-Process Research and Development Goodwill

Impairment charge (5,700) —

Impairment charge — —

The Company completes its annual impairment test on October 1 each year, or more frequently if triggering events indicate a possible impairment. The Company continually evaluates financial performance, economic conditions and other relevant developments in assessing if an interim period impairment test is necessary. The Company's goodwill balance at December 31, 2022 and 2021 was $1.9 million. As of December 31, 2022 and 2021, there were no accumulated impairment losses related to goodwill.

During the year ended December 31, 2021, the Company recognized an impairment charge of $5.7 million on its in process research and development ("IPR&D") asset associated with the NPS product candidate, which had been acquired in connection with the Merger, reducing the fair value of the intangible asset to zero as of December 31, 2021.

5. Collaboration and In-License Agreements

As part of its business, the Company enters into in-licensing agreements with third parties that often require milestone and royalty payments based on the progress of the licensed asset through development and commercial stages. Milestone payments may be required, for example, upon approval of the product for marketing by a regulatory agency, and the Company may be required to make royalty payments based upon a percentage of net sales of the product. The expenditures required under these arrangements in any period may be material and are likely to fluctuate from period to period. These arrangements may permit the Company to unilaterally terminate development of the product and thereby avoid future contingent payments; however, the Company is unlikely to cease development if the compound successfully achieves clinical testing objectives.

Exclusive License Agreement with GenFleet Therapeutics (Shanghai) Inc.

On March 31, 2022, the Company entered into an exclusive license agreement with GenFleet pursuant to which GenFleet granted to the Company a sublicensable, royalty-bearing license, under certain of its intellectual property, to develop, manufacture, and commercialize GFH009 for the treatment, diagnosis or prevention of disease in humans and animals in all countries and territories of the world other than mainland China, Hong Kong, Macau and Taiwan (the "GFH009 Territory"). GFH009 is currently in a Phase 1 clinical trial in the United States and China.

In consideration for the exclusive license, the Company has agreed to pay to GenFleet (i) an upfront and technology transfer fee of $10.0 million, $4.5 million of which was payable within 30 days of the effective date of the license agreement which was March 31, 2022, and $5.5 million of which is due upon the first day of the 15th calendar month following the effective date of the license agreement, (ii) development and regulatory milestone payments for up to three indications totaling up to $48.0 million in the aggregate, and (iii) sales milestone payments totaling up to $92.0 million in the aggregate upon the achievement of certain net sales thresholds in a given calendar year. The Company has also agreed to pay GenFleet single-digit tiered royalties based upon a percentage of annual net sales of GFH009 in the GFH009 Territory, with the royalty rate escalating based on the level of annual net sales and ranging from the low to high single digits.

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During the year ended December 31, 2022, the Company expensed $10.0 million related to the acquired technology as in-process research and development based on the assessment that the technology has no alternative future use as the technology and know-how acquired are not currently commercially viable, $4.5 million of which was paid in April 2022 and the remaining $5.5 million expected to be paid by the end of the second quarter of 2023 for which the Company has recorded an acquired in-process research and development payable as of December 31, 2022.

Exclusive License Agreement with Memorial Sloan Kettering Cancer Center ("MSK")

On September 4, 2014, the Company entered into a license agreement (the “Original MSK License Agreement”) with MSK under which the Company was granted an exclusive license to develop and commercialize MSK’s WT1 peptide vaccine technology. The Original MSK License Agreement, unless terminated earlier in accordance with the terms of the Original MSK License Agreement, will continue on a country-by-country and licensed product-by-licensed product basis, until the later of: (i) expiration of the last valid claim embracing such licensed product; (ii) expiration of any market exclusivity period granted by law with respect to such licensed product; or (iii) ten (10) years from the first commercial sale in such country.

On May 25, 2017, the Company and MSK entered into an Amended and Restated Exclusive License Agreement (the “MSK A&R License Agreement”). Under the MSK A&R License Agreement, the Company expanded its license under the original MSK License Agreement, as amended, to include a license to commercially develop certain additional WT1 peptides through a program of exploiting certain patents and other rights covering such peptides. The MSK A&R License Agreement, among other changes, added certain milestone payments for each additional patent licensed product as defined in the MSK A&R License Agreement.

On October 11, 2017, the Company and MSK entered into a second Amended and Restated Exclusive License Agreement (the “Second MSK A&R License Agreement”). Under the Second MSK A&R License Agreement, the Company and MSK extended certain milestone dates for the Company in exchange for increased milestone payments.

The Company incurred $0.1 million of guaranteed minimum royalty payments under the Second MSK A&R License Agreement during the years ended December 31, 2022 and 2021. Such expenses have been included in research and development costs.

The Company incurred $0.1 million and $0.2 million of sublicensing fees payable under the Second MSK A&R License Agreement in connection with the 3DMed Agreement during the years ended December 31, 2022 and 2021, respectively, included in cost of revenue.

Merck & Co., Inc. Clinical Trial Collaboration and Supply Agreement

On September 21, 2017, the Company entered into a clinical trial collaboration and supply agreement (the "Merck Agreement") through a Merck & Co., Inc. subsidiary, Merck Sharp & Dohme B.V. (“Merck subsidiary”), whereby the Company agreed with the Merck subsidiary to collaborate in a research program to evaluate GPS as it is administered in combination with Merck’s PD1 blocker pembrolizumab in a Phase 1/2 clinical trial enrolling patients in up to five cancer indications, including both hematologic malignancies and solid tumors assessing the efficacy and safety of the combination, comparing overall response rates and immune response markers achieved with the combination compared to prespecified rates based on those seen with pembrolizumab alone in comparable patient populations.

In the fourth quarter of 2018, pursuant to the Merck Agreement, the Company initiated a Phase 1/2 multi-arm ("basket" type) clinical study of GPS in combination with Merck & Co., Inc.’s anti-PD-1 therapy, pembrolizumab (Keytruda) in patients with WT1+ relapsed or refractory tumors. In July 2019, the Company dosed the first patient in this trial. In 2020, the Company, together with Merck determined to focus on ovarian cancer (second or third line). In November 2022, the Company reported topline clinical and initial immune response data from the clinical trial which showed that treatment with the combination of GPS and pembrolizumab compared favorably to treatment with anti-PD-1 therapy alone in a similar patient population. The Company plans to present final data from this study at a medical conference in the first half of 2023.

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The University of Texas M. D. Anderson Cancer Center and The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc.

On September 11, 2006, the Company acquired rights and assumed obligations under a license agreement among Apthera and The University of Texas M. D. Anderson Cancer Center (“MDACC”) and The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (“HJF”) which grants exclusive worldwide rights to a U.S. patent covering NPS and several U.S. and foreign patents and patent applications covering methods of using the peptide as a vaccine. Under the terms of this license, the Company is required to pay an annual maintenance fee of $0.2 million, up to $3.8 million for clinical milestone payments, and to pay a tiered royalty in the mid-single digits based on sales of NPS or other therapeutic products developed from the licensed technologies. The Company incurred the annual maintenance fee during the years ended December 31, 2022 and 2021 and the expenses have been included in research and development costs.

6. Fair Value Measurements

The following tables present information about the Company's assets and liabilities measured at fair value on a recurring basis in the consolidated balance sheets (in thousands):

Assets:

Restricted cash equivalents 100 100 — —

Total assets measured and recorded at fair value $ 16,709 $ 16,709 $ — $ —

Liabilities:

Warrants potentially settleable in cash $ 4 $ — $ — $ 4

Contingent consideration — — — —

Total liabilities measured and recorded at fair value $ 4 $ — $ — $ 4

Assets:

Restricted cash equivalents 100 100 — —

Total assets measured and recorded at fair value $ 21,100 $ 21,100 $ — $ —

Liabilities:

Warrants potentially settleable in cash $ 40 $ — $ — $ 40

Contingent consideration 296 — — 296

Total liabilities measured and recorded at fair value $ 336 $ — $ — $ 336

The Company did not transfer any financial instruments into or out of Level 3 classification during the years ended December 31, 2022 and 2021. See Note 10 for a reconciliation of the changes in the fair value of the warrant liability for the year ended December 31, 2022.

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The Company presents the contingent consideration liability at fair value and it is measured at the end of each reporting period using Level 3 inputs. The contingent consideration relates to Galena’s acquisition of Apthera, Inc. in 2011 and the future contingent payments based on the achievement of certain regulatory and net sales milestones relating to NPS. The contingent consideration is payable at the election of the Company in either cash or shares of common stock, provided that the Company may not issue any shares in satisfaction of any contingent consideration unless it has first obtained approval of its stockholders in accordance with Rule 5635(a) of the Nasdaq Marketplace Rules.

A reconciliation of the change in the fair value of the contingent consideration liability for the year ended December 31, 2022 and 2021 is as follows (in thousands):

Fair ValueMeasurementsUsing SignificantUnobservableInputs(Level 3)

Contingent consideration, December 31, 2020 $ 4,633

Change in the estimated fair value of the contingent consideration (4,337)

Contingent consideration, December 31, 2021 296

Change in the estimated fair value of the contingent consideration (296)

Contingent consideration, December 31, 2022 $ —

During the year ended December 31, 2022, the significant unobservable inputs were adjusted in connection with ceasing all development activities of NPS and concluding the Company's extensive out-licensing efforts. See Note 2 for further discussion on how the Company determines the fair value of its contingent consideration.

The following significant unobservable inputs were used in the valuation of the contingent consideration liability:

Unobservable input As of December 31, 2022 As of December 31, 2021

Potential milestone payments $0 - $30 million $0 - $30 million

Discount rate n/a 15.5 %

Cumulative probability of success — % 5.3 %

Projected years of payments n/a 2028 - 2031

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7. Balance Sheet Accounts

Prepaid expenses and other current assets consist of the following (in thousands):

December 31,

Professional fees 82 36

Prepaid expenses and other current assets $ 531 $ 1,589

Accrued expenses and other current liabilities consist of the following (in thousands):

December 31,

Compensation and related benefits 1,439 989

Accrued expenses and other current liabilities $ 6,286 $ 2,640

8. Legal Proceedings, Commitments and Contingencies

Legal Proceedings

From time to time, the Company is subject to various pending or threatened legal actions and proceedings, including those that arise in the ordinary course of its business, which may include employment matters, breach of contract disputes and stockholder litigation. Such actions and proceedings are subject to many uncertainties and to outcomes that are not predictable with assurance and that may not be known for extended periods of time. The Company records a liability in its consolidated financial statements for costs related to claims, including future legal costs, settlements and judgments, when the Company has assessed that a loss is probable and an amount can be reasonably estimated. If the reasonable estimate of a probable loss is a range, the Company records the most probable estimate of the loss or the minimum amount when no amount within the range is a better estimate than any other amount. The Company discloses a contingent liability even if the liability is not probable or the amount is not estimable, or both, if there is a reasonable possibility that a material loss may have been incurred. As of December 31, 2022, there was no pending or threatened litigation.

Contingent Consideration related to Development, Regulatory and Commercial Milestone Payments and Business Combinations

The Company acquires assets still in development and enters into research and development arrangements with third parties that often require milestone and royalty payments based on the progress of the asset through development stages. Milestone payments may be required, for example, upon approval of the product for marketing by a regulatory agency. In certain agreements, the Company is required to make royalty payments based upon a percentage of the sales.

These arrangements may be material individually, and in the unlikely event that milestones for multiple products covered by these arrangements were reached in the same period, the aggregate charge to expense could be material to the results of operations. In addition, these arrangements often give the Company the discretion to unilaterally terminate development of the product, which would allow the Company to avoid making the contingent payments; however, the Company is unlikely to cease development if the compound successfully achieves clinical

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testing objectives. See Note 5 for additional information on the Company’s commitments under collaboration and license agreements and commitments of contingent consideration.

Leases

The Company has a non-cancelable operating lease for certain executive, administrative, and general business office space for its headquarters in New York, New York, which began June 5, 2020, was amended in February 2022 to add additional space, and has a term through December 31, 2024. The Company assessed the lease amendment for the additional space and determined it should be accounted for as a separate contract.

The weighted average discount rate used to account for the Company's operating lease under ASC 842, Leases, is approximately 13.95%. As of December 31, 2022, the leases have a remaining term of 2.0 years.

Rent expense related to the Company's operating lease was approximately $0.5 million and $0.3 million for the years ended December 31, 2022 and 2021, respectively. The Company made cash payments related to operating leases of approximately $0.5 million and $0.3 million during the years ended December 31, 2022 and 2021, respectively.

Future minimum rental payments under the Company's non-cancelable operating lease are as follows as of December 31, 2022 (in thousands):

Total minimum lease payments:

Total future minimum lease payments 1,051

Less: imputed interest (106)

Operating lease liabilities $ 945

9. Stockholders’ Equity

Preferred Stock

The Company has authorized up to 5,000,000 shares of preferred stock, $0.0001 par value per share, for issuance. There were no preferred shares outstanding as of December 31, 2022 and 2021.

Common Stock

The Company has authorized up to 350,000,000 shares of common stock, $0.0001 par value per share, for issuance.

On April 5, 2022, the Company consummated an underwritten public offering (the "April 2022 Offering"), issuing 4,629,630 shares of common stock and accompanying common stock warrants to purchase an aggregate of 4,629,630 shares of common stock. The shares of common stock and accompanying common stock warrants were sold at a combined price of $5.40 per share and accompanying common stock warrant. Each common stock warrant sold with the shares of common stock represents the right to purchase one share of the Company’s common stock at an exercise price of $5.40 per share. The common stock warrants are exercisable immediately and will expire on April 5, 2027, five years from the date of issuance. The net proceeds to the Company from the April 2022 Offering, after deducting the underwriting discounts and commissions and other offering expenses, and excluding the exercise of any warrants, were approximately $23.0 million.

On April 16, 2021, the Company entered into the Sales Agreement with Cantor Fitzgerald & Co. (the "Agent"). From time to time during the term of the Sales Agreement, the Company may offer and sell shares of common stock having an aggregate offering price up to a total of $50.0 million in gross proceeds. The Agent will collect a fee equal to 3% of the gross sales price of all shares of common stock sold. During the year ended

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December 31, 2022, the Company sold 415,005 shares of common stock pursuant to the Sales Agreement at an average price of $2.60 per share for aggregate net proceeds of approximately $1.0 million. Subsequent to December 31, 2022, the Company sold 76,882 shares of common stock pursuant to the Sales Agreement at an average price of $3.59 for aggregate net proceeds of approximately $0.3 million. There remains approximately $39.2 million available for future sales of shares of common stock under the Sales Agreement. Other than the Sales Agreement, the Company currently does not have any commitments to obtain additional funds.

Shares of common stock reserved for future issuance are as follows (in thousands):

Warrants outstanding 5,141

Stock options outstanding 1,040

Restricted stock units outstanding 255

Shares reserved for future issuance under the Employee Stock Purchase Plans 275

Total shares of common stock reserved for future issuance 7,352

10. Warrants to Acquire Shares of Common Stock

The following is a summary of the Company's warrants to acquire shares of common stock activity for the year ended December 31, 2022 (in thousands, except per share data):

Warrants classified as equity:

On February 28, 2023, in connection with closing of the February 2023 Offering, the Company entered into amendments to an aggregate of 3,438,851 warrants issued by the Company in the April 2022 Offering to reduce the exercise price of such warrants to $3.62, the average closing price of the Company’s common stock, as reported on the Nasdaq Capital Market, for the five trading days immediately preceding the pricing of the February 2023 Offering.

Warrants to acquire shares of common stock primarily consist of equity-classified warrants. In addition, warrants to acquire shares of common stock that may require the Company to settle in cash are liability-classified warrants.

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Warrants Classified as Equity

Equity-classified warrants consist of warrants to acquire common stock issued in connection with previous equity financings. During its evaluation of equity classification for warrants to acquire shares of common stock, the Company considered the conditions as prescribed within ASC 815-40, Derivatives and Hedging, Contracts in an Entity’s own Equity (“ASC 815-40”). The conditions within ASC 815-40 are not subject to a probability assessment. The warrants to acquire shares of common stock do not fall under the liability criteria within ASC 480, Distinguishing Liabilities from Equity, as they are not puttable and do not represent an instrument that has a redeemable underlying security. The warrants to acquire shares of common stock do meet the definition of a derivative instrument under ASC 815, but are eligible for the scope exception as they are indexed to the Company’s own stock and would be classified in permanent equity if freestanding.

Warrants Classified as Liabilities

Liability-classified warrants consist of warrants to acquire common stock issued in connection with previous equity financings. These warrants may be settled in cash and were determined to not be indexed to the Company’s common stock. The liability-classified warrants are grouped within other warrants outstanding in the table above. The estimated fair value of outstanding warrants accounted for as liabilities is determined at each balance sheet date. Any decrease or increase in the estimated fair value of the warrant liability since the most recent balance sheet date is recorded in the consolidated statement of operations as a change in fair value of warrant liability. The fair value of the warrants accounted for as liabilities is estimated using a Black-Scholes pricing model with the following inputs:

As of December 31,

Risk free interest rate 4.75 % 0.65 %

Expected term (years) 0.75 1.75

Expected dividend yield — % — %

The changes in fair value of the warrant liability for the year ended December 31, 2022 and 2021 were as follows (in thousands):

Warrant Liability

Warrant liability, December 31, 2020 $ 55

Change in fair value of warrants (15)

Change in fair value of warrants (36)

Warrant liability, December 31, 2022 $ 4

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11. License Revenue with 3D Medicines, Inc.

Exclusive License Agreement with 3D Medicines, Inc.

In December 2020, the Company, together with its wholly-owned subsidiary, SLSG Limited, LLC, entered into the 3DMed License Agreement with 3DMed, pursuant to which the Company granted 3DMed a sublicensable, royalty-bearing license, under certain intellectual property owned or controlled by the Company, to develop, manufacture and have manufactured, and commercialize GPS and heptavalent GPS (referred to as GPS Plus) product candidates ("GPS Licensed Products") for all therapeutic and other diagnostic uses in the 3DMed Territory. The license is exclusive except with respect to certain know-how that has been non-exclusively licensed to the Company and is sublicensed to 3DMed on a non-exclusive basis. The Company has retained development, manufacturing and commercialization rights with respect to the GPS Licensed Products in the rest of the world.

In partial consideration for the rights granted by the Company, 3DMed agreed to pay the Company (i) a one-time upfront cash payment of $7.5 million, and (ii) milestone payments totaling up to $194.5 million in the aggregate upon the achievement of certain technology transfer, development and regulatory milestones, as well as sales milestones based on certain net sales thresholds of GPS Licensed Products in the 3DMed Territory in a given calendar year. 3DMed also agreed to pay tiered royalties based upon a percentage of annual net sales of GPS Licensed Products in the 3DMed Territory ranging from the high single digits to the low double digits.

Revenue Recognition

The Company evaluated the 3DMed License Agreement and concluded that 3DMed was a customer and the contract should be evaluated under ASC 606. In determining the appropriate amount of revenue to be recognized under ASC 606 as the Company fulfills its obligations under the Agreement, the Company performs the following steps: (i) identifies the promised goods or services in the contract; (ii) determines whether the promised goods or services are performance obligations including whether they are distinct in the context of the contract; (iii) measures the transaction price, including any constraints on variable consideration; (iv) allocates the transaction price to the performance obligations; and (v) recognizes revenue when (or as) the Company satisfies each performance obligation.

The Company determined the initial transaction price of the single performance obligation to be $9.5 million, which includes the $7.5 million upfront fee as well as $2.0 million in development milestones that were assessed to be probable of being achieved at the inception of the 3DMed License Agreement and therefore were not constrained. During the year ended December 31, 2021, the Company recognized the remaining $7.6 million of the initial transaction price as license revenue. As of December 31, 2021, the full $9.5 million initial transaction price was fully recognized as licensing revenue. The Company determined that the remaining $192.5 million in certain future development, regulatory, and sales milestones is variable consideration subject to constraint at inception. At the end of each reporting period, the Company reevaluates the probability of achievement of the future development, regulatory, and sales milestones subject to constraint and, if necessary, will adjust its estimate of the overall transaction price. Any such adjustments will be recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment.

On March 31, 2022, the Company announced that an IND application filed by 3DMed for a small Phase 1 clinical trial investigating safety of GPS in China was approved by China's NMPA. The IND approval by the NMPA triggered a $1.0 million milestone payment to the Company which was recognized as licensing revenue in the first quarter of 2022 and payment was received in May 2022. An additional $191.5 million in potential future development, regulatory, and sales milestones, not including future royalties, remains under the 3DMed License Agreement as of December 31, 2022, which milestones are variable in nature and not under the Company's control.

For the sales-based royalties, the Company will recognize revenue when the related sales occur. To date, the Company has not recognized any royalty revenue resulting from any of its licensing arrangements.

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Cost of Contract Acquisition

The Company incurred contract acquisition costs (commissions) recorded as a contract asset amounting to approximately $1.4 million at inception of the 3DMed License Agreement which were capitalized under ASC 340-40 as incremental costs of obtaining the 3DMed License Agreement. These costs were amortized through general and administrative expense over the technology transfer period, commensurate with when the license revenue was recognized. The Company recognized $1.1 million in expense associated with these costs during the year ended December 31, 2021. There were no such costs during the year ended December 31, 2022.

Cost of License Revenue

The Company incurred $0.1 million and $0.2 million of sublicensing fees payable under the Second MSK A&R License Agreement in connection with the 3DMed License during the year ended December 31, 2022 and 2021, respectively.

12. Stock-Based Compensation

2017 Equity Incentive Plan

On December 29, 2017, the 2017 Equity Incentive Plan was approved by the stockholders of the Company, and currently allows for issuance of up to approximately 22,000 shares of common stock underlying stock options granted prior to September 10, 2019. The 2017 Equity Incentive Plan was terminated upon the approval of the 2019 Incentive Plan subject to outstanding stock options granted under the 2017 Equity Incentive Plan that remain exercisable through maturity for the Company's employees and directors.

2019 Equity Incentive Plan

On September 10, 2019, the 2019 Equity Incentive Plan was approved by the stockholders of the Company, which currently allows for issuance of up to approximately 1,964,000 shares of common stock in connection with the grant of stock-based awards, including stock options, restricted stock, restricted stock units, stock appreciation rights and other types of awards as deemed appropriate.

The number of shares reserved for issuance under the 2019 Equity Incentive Plan automatically increased on January 1 of each year up to and including January 1, 2023, by an amount equal to the lesser of (i) 5% of the total number of shares of common stock outstanding at the end of the prior fiscal year; and (ii) an amount determined by the board of directors or authorized committee. As of December 31, 2022, approximately 641,000 shares of common stock were reserved for future grants under the 2019 Equity Incentive Plan. The number of shares reserved for issuance under the 2019 Equity Incentive Plan was automatically increased to approximately 1,691,000 on January 1, 2023.

The following table summarizes the components of stock-based compensation expense in the consolidated statements of operations for the years ended December 31, 2022 and 2021, respectively (in thousands):

Years Ended December 31,

Research and development $ 270 $ 126

General and administrative 1,456 885

Total stock-based compensation $ 1,726 $ 1,011

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Options to Purchase Shares of Common Stock

The Company uses the Black-Scholes option-pricing model to estimate the fair value of stock-based awards and the following assumptions were used for stock options granted during the years ended December 31, 2022 and 2021, respectively:

Years Ended December 31,

Risk free interest rate 1.96 % 1.05 %

Expected lives (years) 6.18 6.18

Expected dividend yield — % — %

The weighted-average grant date fair value of options granted during the years ended December 31, 2022 and 2021 was $4.52 and $6.98, respectively.

The Company’s expected common stock price volatility assumption is based upon the Company's own implied volatility in combination with the implied volatility of a basket of comparable companies. The expected life assumptions for employee grants were based upon the simplified method, which averages the contractual term of the Company’s options of ten years with the average vesting term of four years for an average of six years. The expected life assumptions for non-employees were based upon the contractual term of the option. The dividend yield assumption is zero because the Company has never paid cash dividends and presently has no intention to do so. The risk-free interest rate used for each grant was also based upon prevailing short-term interest rates. The Company accounts for forfeitures as they occur, therefore, outstanding stock options equal vested and expected to vest stock options.

As of December 31, 2022, there was $2.9 million of unrecognized compensation cost related to outstanding stock options that is expected to be recognized as a component of the Company’s operating expenses over a weighted-average period of 2.55 years.

The following table summarizes stock option activity of the Company for the years ended December 31, 2022 and 2021, respectively: