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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 developing novel cancer immunotherapeutics for a broad range of cancer indications. Our product candidates currently include galinpepimut-S and nelipepimut-S.

Galinpepimut-S, or GPS

Our lead product candidate, galinpepimut-S, or GPS, is a cancer immunotherapeutic agent licensed from Memorial Sloan Kettering Cancer Center, or MSK, that targets the Wilms tumor 1, or 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 a Phase 3 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. 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 & Drug Administration, or the FDA. The REGAL study is expected to enroll approximately 116 patients at up to approximately 85 clinical sites primarily in the United States, Europe, and Asia with a planned interim safety and futility analysis after 80 events (deaths).

At the request of several investigators, we are planning to institute an Expanded Access Program that would allow qualified physicians who desire so to treat with GPS AML patients who do not meet currently required study entry criteria for the ongoing REGAL trial.The access will be provided on a case by case basis to patients in the U.S. and, potentially, Germany. Patients treated under the Expanded Access Program will not be considered participants in the REGAL study.We expect the program to commence in the second quarter of 2022.

In December 2018, 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, Keytruda® (pembrolizumab). Thetumor type currently being studied is ovarian cancer (second or third line). In February 2022, we announced that we had completed enrollment of 17 evaluable patients in this Phase 1/2 clinical trial. Data from 15 patients is expected to be examined by mid-2022, with final data analysis of all 17 evaluable patients in the study by the end of 2022.

In February 2020, a Phase I 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. Completion of enrollment of a target total of 10 evaluable patients is expected during the second half of 2022.

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, malignant pleural mesothelioma, or MPM, and multiple myeloma, or MM, as well as Fast Track Designation for AML, MPM, and MM from the FDA.

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Nelipepimut-S or NPS

Nelipepimut-S, or NPS, is a cancer immunotherapy that targets human epidermal growth factor receptor 2, or HER2, expressing cancers. We have presented data from Phase 2 studies of NPS in different types of breast cancers, which we considered to be the lead indication for NPS; however, we do not currently plan to conduct or fund a Phase 3 program for NPS. Following extensive efforts over the past four years to out-license NPS for further development in breast cancer, we have concluded that continued effort to seek a licensee for NPS for breast cancer will not result in a transaction which would provide value for the asset to us or our shareholders. We are reviewing our options for NPS.

Financial Position

At December 31, 2021, we had cash and cash equivalents of $21.4 million. We have incurred operating losses since inception and have not generated any product sales revenue or achieved profitable operations. We incurred net losses of $20.7 million and $16.8 million for the years ended December 31, 2021 and 2020, respectively. Our accumulated deficit as of December 31, 2021 was $138.6 million, and we expect to continue to incur substantial losses in future periods.

Our operating expenses will increase substantially as we continue to advance our product candidates assuming we receive sufficient funding to continue our ongoing studies and initiate our planned studies. We anticipate that our expenses will increase as we:

•complete our ongoing and planned clinical trials, including the REGAL study;

•continue the research, development and scale-up of manufacturing capabilities to optimize products and dose forms for which we may obtain regulatory approval;

•scale up manufacturing for GPS, including manufacturing validation activities;

•maintain, expand and protect our global intellectual property portfolio; and

•hire additional personnel, including clinical, manufacturing, and scientific personnel, sales and marketing personnel, and general and administrative personnel.

We intend to use our existing cash and cash equivalents for working capital and to fund the research and development of our product candidates. We believe that our existing cash and cash equivalents as of December 31, 2021 will not be sufficient to fund our current planned operating expenses for at least the next twelve months from the date of issuance of these financial statements.

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Impact of COVID-19

The ongoing global COVID-19 pandemic, including the surges of cases from the Delta and Omicron variants, continues to disrupt our business operations and those of our contractors, contract research organizations, or CROs, suppliers, clinical sites, contract manufacturing organizations, or CMOs, and other partners.The COVID-19 pandemic could affect the health and availability of our workforce and that of the third-parties we rely on, such as our CROs, clinical sites, CMOs, and other contractors as well as the governmental agencies, such as the FDA and health authorities in other countries which could delay or otherwise adversely impact the ability of such parties to fulfill their obligations. We have implemented a return-to-work policy in compliance with federal, state and local requirements and guidance, which provides for a hybrid of remote and in-office work, and we operated on such a semi-virtual basis in 2021. We are continuously monitoring the impact of the pandemic on our clinical development programs. Our Phase 3 REGAL study is progressing, with the necessary work to activate additional sites in the United States and Europe continuing. However, since the onset of the COVID-19 pandemic, we have observed that, at certain times and in certain instances, clinical site initiations, patient screening and patient enrollment have been delayed. These delays are likely due to many reasons, which have been changing and evolving as the COVID-19 pandemic itself has evolved, including the prioritization of hospital resources towards the care of patients with COVID-19, delays in reviews and approvals by independent institutional review boards, or IRBs, and/or ethics committees at clinical sites, the challenges for clinicians and patients to comply with clinical trial protocols due to quarantines impeding patient movement or interrupting operations at sites, restrictions on travel and, most recently, inadequate staffing at clinical sites, supply chain-related delays, and materials shortages. Throughout the United States, Europe and Asia, newly initiated sites have taken longer than expected to become fully operational and begin enrolling patients. We have taken several steps to mitigate these actual and potential delays, including increasing the number of clinical sites from 50 to up to approximately 85, increasing the number of additional countries, both in Europe and Asia, in which sites were or will be initiated, allocating additional resources, including additional CROs and internal personnel, to the REGAL study, and making certain changes to the protocol for the study. We are continuing to monitor each clinical site through our CROs as well as conducting direct outreach to investigators and study staff through site visits investigator meetings and other modes of communication. Accordingly, due to the accumulation of these delays over the past two years, we have adjusted the projected timing of the REGAL study. The full extent to which the COVID-19 pandemic will continue to directly or indirectly impact our business, results of operations and financial condition will depend on future developments that are highly uncertain, subject to change and cannot be predicted with confidence, including the duration of the outbreak, the continued availability and efficacy of vaccines, new information which may emerge concerning the severity of COVID-19, the emergence of new variants of COVID-19, and the actions to contain COVID-19 or treat its impact, among others.

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Components of Results of Operations

License Revenue

License revenue consists of revenue recognized pursuant to our Exclusive License Agreement with 3D Medicines Inc., or 3DMed, dated December 7, 2020, or the 3DMed 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 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 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 of clinical sites included in the trials;

•the length of time required to enroll suitable patients;

•the number 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;

•the receipt of marketing approvals; and

•the commercialization of current and future product candidates.

Research and development activities are central to our business model. Cancer immunotherapy 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.

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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. Cancer immunotherapy product commercialization may take several years and millions of dollars in development costs.

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 NPS that was acquired as part of the merger with Galena Biopharma, Inc. in 2017, or the Merger. 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 (Expense), Net

Non-operating income (expense), net 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, 2021 and 2020

The following table summarizes our results of operations for the years ended December 31, 2021 and 2020 (amounts in thousands):

Year ended December 31,

Operating expenses:

Cost of license revenue 200 — 200

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

For the year ended December 31, 2021, our net loss was $20.7 million compared with a net loss of $16.8 million for the year ended December 31, 2020. The increase of $3.9 million in net loss was primarily attributable to an increase in operating expenses of $14.0 million, driven by a $6.4 million increase in research and development expenses, a $5.7 million non-cash impairment charge of IPR&D, a $1.7 million increase in general and administrative expenses, and a $0.2 million increase in costs of license revenue. These increases in operating expenses were partially offset by a $5.7 million increase in licensing revenue, a $4.2 million increase in non-operating income, and a $0.2 million increase in income tax benefit.

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

License Revenue

License revenue for the year ended December 31, 2021 was $7.6 million compared to $1.9 million for the year ended December 31, 2020 and related to the out-licensing of intellectual property rights and transfer of technical know-how associated with the 3DMed Agreement for the development and commercialization of GPS in China, Hong Kong, Macau, and Taiwan.

Cost of License Revenue

We incurred $0.2 million of sublicensing fees payable under our license from MSK in connection with the 3DMed Agreement during year ended December 31, 2021. There was no cost of license revenue during the year ended December 31, 2020.

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Research and Development

Research and development expenses were $15.7 million for the year ended December 31, 2021 compared to $9.3 million for the year ended December 31, 2020. As compared to the prior period, the $6.4 million increase in research and development expenses was primarily attributable to a $4.3 million increase in clinical trial expenses primarily related to our ongoing Phase 3 REGAL clinical trial of GPS in AML, a $1.7 million increase in manufacturing and drug supply costs due to the ramp up of the manufacture of clinical trial materials and registration batches of GPS, a technology transfer to a new contract manufacturer, and clinical drug supply purchase costs in the European Union as we prepared to open sites and enroll patients in European Union countries for our Phase 3 REGAL clinical trial for GPS in AML, and a $0.5 million increase in personnel related expenses due to increased headcount. These increases were partially offset by a $0.1 million decrease in other research and development expenses. 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.

General and Administrative

General and administrative expenses were $11.3 million for the year ended December 31, 2021 compared to $9.6 million for the year ended December 31, 2020. The $1.7 million increase was primarily driven by a $1.1 million amortization expense of our contract asset associated with the 3DMed License Agreement and a $0.9 million increase in personnel related expenses, including a $0.3 million increase in non-cash stock-based compensation. These increases were partially offset by a $0.3 million decrease in other general and administrative expenses.

In-Process Research and Development Impairment Charge

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, Net

Non-operating income, net for the years ended December 31, 2021 and 2020, respectively, was as follows (in thousands):

Years Ended December 31,

Change in fair value of warrant liability $ 15 $ (97) $ 112

Change in fair value of contingent consideration 4,337 279 4,058

The increase in our net non-operating income during the year ended December 31, 2021 compared to the year ended December 31, 2020 was primarily due to a $4.1 million increase in the change in fair value of contingent consideration, and a $0.1 million increase in the change in the fair value of liability-classified warrants to acquire shares of our common stock. The change in estimated fair value of contingent consideration is driven by changes in discount periods and rates, changes in the timing of development milestones achieved and changes in probability assumptions with respect to the likelihood of achieving the various earnout criteria. The $4.3 million change in 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. The change in the estimated fair value of our warrant liability was primarily due to the changes in our common stock price.

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Interest income for the years ended December 31, 2021 and 2020 consists of nominal interest earned from our cash and cash equivalents. 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

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. For the year ended December 31, 2020, we recognized a de minimis income tax benefit.

Liquidity and Capital Resources

We have not generated any revenue from product sales in the years ended December 31, 2021 and 2020. Since inception, we have incurred net losses, used net cash from our operations, and have funded substantially all of our operations through proceeds from the sale of debt and equity securities. During the year ended December 31, 2021, we incurred a net loss of $20.7 million, used $26.0 million of cash in operations, and had an accumulated deficit of $138.6 million as of December 31, 2021. 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, 2021, we had cash and cash equivalents of $21.4 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. These conditions give rise to a substantial doubt over our ability to continue as a going concern.

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. 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.

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, 2021, we sold 786,927 shares of common stock pursuant to the Sales Agreement at an average price of $12.04 per share for aggregate net proceeds of approximately $9.0 million. Other than the Sales Agreement, we currently do not have any commitments to obtain additional funds.

During the year ended December 31, 2021, we received $3.1 million from the exercise of warrants to acquire shares of common stock.

During the year ended December 31, 2021, we received $2.0 million from milestones achieved pursuant to the 3DMed Agreement. In January 2022, we announced that an IND application for a small Phase I clinical trial investigating safety of GPS in China was accepted by China's National Medical Products Administration, or the NMPA. On March 30, 2022, the IND was approved by the NMPA triggering a $1.0 million milestone payment to the Company which is expected to be received in the second quarter of 2022. 3D Medicines expects to initiate the trial by mid-2022 and will be responsible for all expenses related to executing the trial in China. The current clinical development plan provides for initiation of a Phase II clinical trial following receipt of satisfactory safety data from the Phase I study; the initiation of the Phase II study will also trigger a milestone payment to us which we expect will occur in the second half of 2022. Total remaining potential milestone payments to us under the 3DMed Agreement between total $192.5 million, not including future royalties.

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We will require substantial additional financing to develop any current or future product candidates. Alternatively, 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, and may be unable to obtain sufficient funding in the future on acceptable terms, if at all. 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, payments from potential strategic research and development collaborations, and licensing and/or marketing arrangements with pharmaceutical companies. Additionally, we continue to pursue discussions with global and regional pharmaceutical companies for licensing and/or co-development rights to our late- and early-stage pipeline candidates. There can be no assurance that these future funding efforts will be successful. If we cannot obtain the necessary funding, we will need to delay, scale back or eliminate some or all of our research and development programs; consider other various strategic alternatives, including a merger or sale; or cease operations.

Our future operations are highly dependent on a combination of factors, including (i) the timely and successful completion of additional financing, (ii) our ability to complete revenue-generating partnerships with pharmaceutical 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 proposed future products.

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, 2021 and 2020 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, 2021 and 2020 (in thousands):

For the December 31,

Net cash (used in) provided by:

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Net Cash Flow from Operating Activities

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 is 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 operating activities of $10.4 million during the year ended December 31, 2020 was primarily attributable to our net loss of $16.8 million. This amount was offset by a change in our operating assets and liabilities of $5.9 million and various net non-cash charges of $0.5 million These noncash charges were comprised of $0.6 million in non-cash stock-based compensation expense and $0.2 million in other noncash charges. These amounts were partially offset by a gain of $0.3 million from the decrease in the fair value of our contingent consideration liability. The net change in our operating assets and liabilities is primarily attributable to an increase in deferred revenue related to our 3DMed License Agreement.

Net Cash Flow from Financing Activities

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.

We generated $38.4 million of net cash from financing activities for the year ended December 31, 2020, which was primarily attributable to $29.9 million in net proceeds from the sale of common stock, common stock pre-funded warrants, and common stock warrants and $8.5 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 for our lease agreement for office space at the premises that expire in December 2024 in New York, New York. As of December 31, 2021, our contractual commitments for our lease was $1.5 million, which will be paid over the term of the lease. The amount of lease commitments reflects payments due for additional premises under an amendment to our lease agreement that had not commenced as of December 31, 2021, and as a result, our future lease payments as of December 31, 2021 was $1.0 million. On February 21, 2022, the Company took possession of the additional premises and the lease amendment commenced. 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 have 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.

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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 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.

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 Form10-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 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.

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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.

Valuation of Intangible Assets

Intangible assets are comprised of identifiable IPR&D acquired in conjunction with the completion of the Merger and are considered indefinite-lived intangible assets and are assessed for impairment annually during the fourth quarter of each fiscal year or more frequently if impairment indicators exist.

The identifiable intangible assets are measured at their respective fair values as of the acquisition date and may be subject to revision within the measurement period, which may be up to one year from the acquisition date. The models used in valuing these intangible assets require the use of significant estimates and assumptions including but not limited to:

•estimates of revenue and operating profits related to products or product candidates;

•the probability of success for unapproved product candidates considering their stages of development;

•the time and resources needed to complete the development and approval of product candidates;

•the life of the potential commercialized products and associated risks, including the inherent difficulties and uncertainties in developing a product candidate such as obtaining FDA and other regulatory approvals; and

•risks related to the viability of and potential alternative treatments in any future target markets.

We believe that the fair values used to record intangible assets acquired in connection with a business combination use information known and knowable, and are based upon reasonable estimates and assumptions given the facts and circumstances as of the related valuation dates.

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Intangible assets related to IPR&D are considered to be indefinite-lived until the completion or abandonment of the associated research and development efforts. If and when development is complete, which generally occurs if and when regulatory approval to market a product is obtained, the associated assets would be deemed finite-lived and would then be amortized based on their respective estimated useful lives at that point in time. During the period the assets are considered indefinite-lived, they are not amortized but are tested for impairment on an annual basis as well as between annual tests if we become aware of any events or changes that would indicate that it is more likely than not that the fair value of the IPR&D is below their respective carrying amounts. The fair value of our indefinite-lived intangible assets is dependent on assumptions such as the expected timing or probability of achieving the specified milestones, changes in projected revenues or changes in discount rates. Significant judgment is employed in determining these assumptions and changes to our assumptions could have a significant impact on our results of operations in any given period.

When performing our impairment assessment, we calculate the fair value using the same methodology as described above. If the carrying value of our IPR&D exceeds its fair value, then the intangible asset is written down to its fair value. Changes in estimates and assumptions used in determining the fair value of our IPR&D could result in an impairment. Impairment charges are recorded within our consolidated statements of operations. Based on our most recent impairment assessment we incurred a $5.7 million impairment charge for the year ended December 31, 2021, mainly related to our determination that the execution of 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. See Note 4, Goodwill and Intangible Assets, to our consolidated financial statements included in this report.

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, 2021 and 2020.

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.

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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.

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. During the fourth quarter of 2021, we changed the valuation technique of net sales milestones from a probability adjusted, discounted cash flow approach to the option pricing model with Monte Carlo simulation.

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.

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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, 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. For non-employee awards, we use the remaining contractual term.

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.

Recent Accounting Pronouncements Adopted

In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740):Simplifying the Accounting for Income Taxes which, among other things, eliminates certain exceptions in the current rules regarding the approach for intra-period tax allocations and the methodology for calculating income taxes in an interim period, and clarifies the accounting for transactions that result in a step-up in the tax basis of goodwill. The standard was adopted by the Company on January 1, 2021. This new standard 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 early adoption is permitted. The Company is currently evaluating the potential impact of the adoption of this standard on its consolidated financial statements.

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

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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 128

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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, 2021 and 2020, 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, 2021 and 2020, 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.

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/s/ Moss Adams LLP

San Francisco, California

March 31, 2022

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

Contract asset — 1,128

Prepaid expenses and other current assets 1,589 395

Operating lease right-of-use asset 723 896

In-process research and development — 5,700

Deposits and other assets 594 614

LIABILITIES AND STOCKHOLDERS’ EQUITY

Current liabilities:

Accrued expenses and other current liabilities 2,640 1,913

Operating lease liability 198 166

Deferred revenue — 5,600

Operating lease liability, non-current 610 825

Deferred tax liability — 239

Warrant liability 40 55

Commitments and contingencies (Note 8)

Stockholders’ equity:

Total liabilities and stockholders’ equity $ 26,275 $ 46,049

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:

Cost of revenue 200 —

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

Non-operating income (expense):

Change in fair value of warrant liability 15 (97)

Change in fair value of contingent consideration 4,337 279

Interest income, net 6 26

Total non-operating income, net 4,358 208

Income tax benefit (237) (17)

Deemed dividend arising from warrant modifications — (78)

Net loss attributable to common stockholders $ (20,699) $ (16,835)

Per share information:

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 upon exercise of pre-funded warrants 448,800 — 4 — 4

Stock-based compensation — — 578 — 578

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

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:

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

Non-cash stock-based compensation 1,011 578

Non-cash lease expense 173 95

Change in fair value of contingent consideration (4,337) (279)

Change in fair value of common stock warrants (15) 97

Deferred income taxes (239) (23)

Changes in operating assets and liabilities:

Prepaid expenses and other assets (1,174) 84

Accrued expenses and other current liabilities 727 742

Operating lease liabilities (183) —

Net cash used in operating activities (26,021) (10,417)

Cash flows from financing activities:

Proceeds from issuance of common stock, net of issuance costs 9,005 29,599

Proceeds from exercise of warrants 3,069 8,535

Collection of stock subscription receivable — 308

Net cash provided by financing activities 12,074 38,442

Supplemental disclosure of cash flow information:

Cash received during the year for interest $ 6 $ 26

Supplemental disclosures:

Contract asset within accounts payable $ — $ 1,410

Reclassification of warrant liabilities upon exercise $ — $ 94

Right-of-use assets recorded $ — $ 976

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 cancer immunotherapeutics for a broad range of cancer indications. SELLAS’ lead product candidate, galinpepimut-S ("GPS"), is 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 to address a broad spectrum of hematologic malignancies and solid tumor indications. SELLAS’ second product candidate, nelipepimut-S ("NPS"), is a HER2-directed cancer immunotherapy.

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 Accounting Standard Codification (ASC) 205-40.

Since inception, the Company has incurred recurring losses and negative cash flows from operations and has an accumulated deficit of $138.6 million as of December 31, 2021. During the year ended December 31, 2021, the Company incurred a net loss of $20.7 million and used $26.0 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, 2021, the Company had cash and cash equivalents of $21.4 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. 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 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, 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 SEC on April 16, 2021 and declared effective on April 29, 2021. During the year ended December 31, 2021, the Company sold 786,927 shares of common stock pursuant to the Sales Agreement at an average price of $12.04 per share for aggregate net proceeds of approximately $9.0 million. Other than the Sales Agreement, the Company currently does not have any commitments to obtain additional funds.

During the year ended December 31, 2021, the Company received $3.1 million from the exercise of warrants to acquire shares of the Company's common stock.

During the year ended December 31, 2021, the Company received $2.0 million from milestones achieved pursuant to the 3DMed Agreement (See Note 11). In January 2022, the Company announced that an IND application for a small Phase I clinical trial investigating safety of GPS in China was accepted by China's National Medical Products Administration ("NMPA"). 3D Medicines expects to initiate the trial by mid-2022 and will be responsible for all expenses related to executing the trial in China. On March 30, 2022, the IND was approved by the NMPA triggering a $1.0 million milestone payment to the Company which is expected to be received in the second quarter of 2022. The current clinical development plan provides for initiation of a Phase II clinical trial following receipt of satisfactory safety data from the Phase I study; the initiation of the Phase II study will also trigger a milestone payment to the Company which is expected in the second half of 2022. Total remaining potential milestone payments to the Company under the 3DMed Agreement total $192.5 million, not including future royalties.

The Company will require substantial additional financing to commercially develop any current or future product candidates. Alternatively, the Company 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, and may be unable to obtain sufficient funding in the future on acceptable terms, if at all. 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, payments from potential strategic research and development collaborations, and licensing and/or marketing arrangements with pharmaceutical companies. Additionally, the Company continue to pursue discussions with global and regional pharmaceutical companies for licensing and/or co-development rights to its product candidates. There can be no assurance that these future funding efforts will be successful. If the Company cannot obtain the necessary funding, the Company will need to delay, scale back or eliminate some or all of its research and development programs; consider other various strategic alternatives, including a merger or sale; or cease operations.

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”).

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.

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SELLAS LIFE SCIENCES GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS - Continued

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 IPR&D and any related impairment, carrying value of goodwill, fair value of contingent purchase price consideration, 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.

Reclassifications

Certain prior year amounts have been reclassified to conform to current year presentation. These reclassifications had no effect on the Company's loss from operations, net loss, and net loss per share.

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, 2021 and 2020, 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, 2021 and 2020, 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 multiple financial institutions, the balances of which frequently exceed federally insured limits.

Impact of COVID-19

The ongoing global COVID-19 pandemic, including the surges of cases from the Delta and Omicron variants, continues to disrupt the Company’s business operations and those of its contractors, contract research organizations (“CROs”), suppliers, clinical sites, contract manufacturing organizations (“CMOs”), and other partners.The COVID-19 pandemic could affect the health and availability of the Company’s workforce and that of the third-parties it relies on, such as its CROs, clinical sites, CMOs, and other contractors as well as the governmental agencies, such as the U.S. Food and Drug Administration (“FDA”) and health authorities in other countries which could delay or otherwise adversely impact the ability of such parties to fulfill their obligations. The Company is continuously monitoring the impact of the pandemic on its clinical development programs. The full extent to which the COVID-19 pandemic will continue to directly or indirectly impact the Company’s business, results of operations and financial condition will depend on future developments that are highly uncertain, subject to change and cannot be predicted with confidence, including the duration of the outbreak, the continued availability and efficacy of vaccines, new information which may emerge concerning the severity of COVID-19, the emergence of new variants of COVID-19, and the actions to contain COVID-19 or treat its impact, among others.

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, 2021 and 2020, on hand with the Company's financial institutions as collateral for its corporate credit cards.

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SELLAS LIFE SCIENCES GROUP, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS - Continued

Intangible Assets

As part of the business combination with Galena, the Company acquired certain in-process research and development (“IPR&D”) assets, which were capitalized as intangible assets. Costs to develop these assets are recorded in research and development expense as incurred in the Company’s consolidated statements of operations.

The Company’s intangible assets were comprised of identifiable assets which are considered indefinite-lived intangible assets and are assessed for impairment annually in the fourth quarter of each fiscal year or more frequently if impairment indicators exist. In the fourth quarter of 2021 as part of its annual impairment analysis, the Company measured the fair value of the IPR&D asset, nelipepimut-S ("NPS"), by estimating the costs to develop the acquired technology into commercially viable products, estimating the resulting revenue from the projects and discounting the related net cash flow to present value. The revenue and cost projections used to value IPR&D were reduced based on the probability of success of developing NPS in other oncology indications outside of breast cancer, given that the Company determined that consummating an out-licensing transaction of NPS for further development in breast cancer was unlikely. Additionally, the projections consider the relevant market sizes and growth factors, expected trends in technology and the nature and expected timing of new product introductions by the Company and its competitors. The rates utilized to discount the net cash flow to their present value are commensurate with the stage of development of the projects and uncertainties in the economic estimates used in the projections. In the fourth quarter of 2021, the fair value of the Company’s NPS IPR&D was determined to exceed its carrying value by $5.7 million, and as such the Company recognized an impairment charge equal to the same amount that was recorded within in-process research and development impairment charge in the Company’s consolidated statements of operations.

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, 2021 and 2020.

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 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. During the fourth quarter of 2021, the Company changed the valuation technique of net sales milestones from a probability adjusted, discounted cash flow approach to the option pricing model with Monte Carlo simulation.

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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 agreement contains 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 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 License Agreement with 3D Medicines Inc.

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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.

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. Payments for a product license prior to regulatory approval of the product and payments for milestones achieved prior to regulatory approval of the product are expensed in the period incurred as research and development expenses. Milestone payments made in connection with regulatory approvals are capitalized and amortized to cost of revenue over the remaining useful life of the asset.

Research and development expenses primarily consist of the intellectual property and research and development materials acquired, expenses from third parties who conduct research and development activities on behalf of the Company as well as related wages, benefits and other operating costs. The Company expenses IPR&D projects acquired as asset acquisitions which have not reached technological feasibility and which have no alternative future use.

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.

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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. For stock price volatility, the Company uses comparable public companies as a basis for its expected volatility to calculate the fair value of option grants as it does not have adequate historical pricing information of its own stock commensurate with the expected term. 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, 2021 or 2020.

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

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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 December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740):Simplifying the Accounting for Income Taxes which, among other things, eliminates certain exceptions in the current rules regarding the approach for intra-period tax allocations and the methodology for calculating income taxes in an interim period, and clarifies the accounting for transactions that result in a step-up in the tax basis of goodwill. The standard was adopted by the Company on January 1, 2021. This new standard did not have a material impact on the Company's 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 early adoption is permitted. The Company is currently evaluating the potential impact of the adoption of this standard on its consolidated financial statements.

In May 2021, ASU No. 2021-04, Issuer’s Accounting for Certain Modifications of Exchanges of Freestanding Equity-Classified Written Call Options was issued 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 is not expected to have a material impact on the consolidated financial statements.

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4. Goodwill and Intangible Assets

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

In-Process Research and Development Goodwill

Impairment charge (5,700) —

In the fourth quarter of 2021, the Company recognized an impairment charge 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 and reduced the fair value of the related IPR&D intangible asset to zero. See Note 2 for discussion on how the Company determined the fair value of its IPR&D. There was no impairment charge during the year ended December 31, 2020.

As of December 31, 2021 and 2020, there were no accumulated impairment losses related to goodwill.

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 sometimes 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 Memorial Sloan Kettering Cancer Center

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

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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, 2021 and 2020. Such expenses have been included in research and development costs.

The Company incurred $0.2 million of sublicensing fees payable under our license from MSK in connection with the 3DMed Agreement during year ended December 31, 2021 included in cost of revenue. There was no cost of license revenue during the year ended December 31, 2020.

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, Keytruda® (pembrolizumab) 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 February 2022, the Company reported that enrollment in the study was completed. Data from the majority of evaluable patients is expected to be examined by mid-2022, with final data analysis for all evaluable patients expected by the end of 2022.

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, 2021 and 2020 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):

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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

Assets:

Restricted cash equivalents $ 100 $ 100

Total assets measured and recorded at fair value $ 35,059 $ 35,059 $ — $ —

Liabilities:

Warrants potentially settleable in cash $ 55 $ — $ — $ 55

Total liabilities measured and recorded at fair value $ 4,688 $ — $ — $ 4,688

The Company did not transfer any financial instruments into or out of Level 3 classification during the years ended December 31, 2021 and 2020. See Note 10 for a reconciliation of the changes in the fair value of the warrant liability for the years ended December 31, 2021.

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 development, 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, 2021 and 2020 is as follows (in thousands):

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Fair ValueMeasurementsUsing SignificantUnobservableInputs(Level 3)

Contingent consideration, December 31, 2019 $ 4,912

Change in the estimated fair value of the contingent consideration (279)

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

Contingent consideration, December 31, 2021 $ 296

During the year ended December 31, 2021, the significant unobservable inputs were adjusted 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 timeline and a lower probability of success associated with earlier stages of clinical development for the potential development of NPS in other oncology indications. 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, 2021 As of December 31, 2020

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

Discount rate 15.5 % 6.6 %

Cumulative probability of success 5.3 % 33.0 %

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7. Balance Sheet Accounts

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

December 31,

Clinical trial costs $ 1,309 $ 95

Professional fees 36 49

Prepaid expenses and other current assets $ 1,589 $ 395

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

December 31,

Compensation and related benefits 989 812

Accrued expenses and other current liabilities $ 2,640 $ 1,913

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. In the opinion of management, as of the date hereof, the amount of liability, if any, with respect to these matters, individually or in the aggregate, will not materially affect the Company’s consolidated results of operations, financial position or cash flows.

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The Company’s predecessor, Galena, was involved in multiple legal proceedings and administrative actions, including stockholder class actions, both state and federal. In 2021, the Company settled all remaining legacy Galena litigation as follows:

•Certain putative shareholder securities class action complaints originally filed against Galena in 2017 which alleged, among other things, that Galena and certain of Galena's former officers and directors failed to disclose that certain of Galena’s promotional practices were allegedly improper and that these alleged failures rendered Galena’s statements about its business misleading. The actions were consolidated with lead plaintiffs named by the U.S. District Court for the District of New Jersey. In 2021, the Company reached a settlement with the plaintiffs in this action which, in November 2021, received preliminary court approval and which was fully covered by our directors and officers insurance policy applicable to this case. Final approval from the court was received on February 24, 2022.

•In March 2017, a derivative complaint was filed in the U.S. District Court for the District of New Jersey against Galena’s former directors and Galena, as a nominal defendant. In July 2017, a derivative complaint was filed in California state court against Galena’s former directors and Galena, as a nominal defendant. In January 2018, a derivative complaint was filed in the U.S. District Court for the District of New Jersey against Galena’s former directors, officers and employees, and the Company as a nominal defendant. These complaints purported to assert derivative claims for breach of fiduciary duty on the Company’s behalf against its former directors and, in certain of the complaints, certain of the Company’s former officers and former employees, based on substantially similar facts as alleged in the putative shareholder securities class action complaint. The Company reached a settlement with the plaintiffs in these three cases which was approved by the U.S. District Court for the District of New Jersey on November 19, 2021, and which was fully covered by the Company's directors and officers insurance policy applicable to these cases.

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

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Leases

The Company has a non-cancelable operating lease for office space in New York, New York, which began June 5, 2020 with a term through December 31, 2024. At inception of the lease, the Company recognized a current operating lease liability of $0.1 million and a non-current operating lease liability of $0.9 million with a corresponding ROU asset of $1.0 million, which is based on the present value of the minimum rental payments of the lease. The discount rate used to account for the Company's operating lease under ASC Topic 842 is the Company’s estimated incremental borrowing rate of 13%. As of December 31, 2021, the lease has a remaining term of 3.0 years.

Rent expense related to the Company's operating lease was approximately $0.3 million and $0.4 million for the years ended December 31, 2021 and 2020, respectively. The Company made cash payments related to operating leases of approximately $0.3 million during each of the years ended December 31, 2021 and 2020.

Future minimum rental payments under the Company's non-cancelable operating lease are as follows as of December 31, 2021 (in thousands):

Total minimum lease payments:

Total future minimum lease payments 962

Less: imputed interest (154)

Operating lease liability $ 808

On December 6, 2021, the Company entered into a sublease amendment to expand its office space in New York, New York. In accordance with the agreement, the commencement of the sublease will not begin until the sublandlord has vacated and made the space available and ready for use, which did not occur until February 21, 2022. Therefore, no amounts associated with the sublease amendment were recognized in the consolidated financial statements for the year ended December 31, 2021. On February 22, 2022, a commencement date was reached as the Company took over the space and will begin making additional rental payments of approximately $0.2 million per year through December 31, 2024.

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, 2021 and 2020.

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 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 December 31, 2021, the Company sold 786,927 shares of common stock pursuant to the Sales Agreement at an average price of $12.04 per share for aggregate net proceeds of approximately $9.0 million.

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On December 13, 2020, the Company entered into a Securities Purchase Agreement with certain investors, pursuant to which the Company agreed to issue and sell, in a registered direct offering by the Company directly to the investors (the “December 2020 Registered Direct Offering”), an aggregate of 2,320,000 shares of common stock, par value $0.0001 per share, of the Company, at an offering price of $7.00 per share for gross proceeds of approximately $16.2 million. The net proceeds to the Company from the December 2020 Registered Direct Offering, after deducting placement agent fees and related offering expenses, was approximately $15.0 million.

On July 31, 2020, the Company entered into a Securities Purchase Agreement with certain investors, pursuant to which the Company agreed to issue and sell, in a private placement directly to the investors (the "July 2020 PIPE Offering"), 2,744,078 shares of its common stock and accompanying warrants to purchase up to an aggregate of 2,744,078 shares of common stock at a combined purchase price of $3.335 per share and accompanying warrant. The warrants were immediately exercisable upon issuance at an exercise price of $3.30 per share and will expire five years from the date of issuance. The July 2020 PIPE Offering closed on August 4, 2020. The net proceeds to the Company from the July 2020 PIPE Offering, after deducting placement agent fees and related offering expenses, were approximately $8.5 million.

On January 9, 2020, the Company entered into a Securities Purchase Agreement with certain investors, pursuant to which the Company agreed to issue and sell, in a registered direct offering by the Company directly to the investors (the “January 2020 Registered Direct Offering”), (i) an aggregate of 1,189,000 shares of common stock, par value $0.0001 per share, of the Company, at an offering price of $3.9825 per share and (ii) an aggregate of 448,800 pre-funded warrants exercisable for shares of common stock at an offering price of $3.9725 per pre-funded warrant, for gross proceeds of approximately $6.5 million before deducting the placement agent fee and related offering expenses. In a concurrent private placement, the Company issued to the Investors who participated in the January 2020 Registered Offering warrants exercisable for up to an aggregate of 818,900 shares of common stock at an exercise price of $3.93 per share. Each warrant was immediately exercisable upon issuance and will expire five and one-half years from the issuance date. The net proceeds to the Company from the January 2020 Registered Direct Offering, after deducting placement agent fees and related offering expenses, and excluding the exercise of any warrants, was approximately $6.0 million.

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

Warrants outstanding 519

Stock options outstanding 534

Restricted stock units outstanding 200

Shares reserved for future issuance under the Employee Stock Purchase Plans 311

Total shares of common stock reserved for future issuance 2,013

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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, 2021 (in thousands, except per share data):

Warrants classified as equity:

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.

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:

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As of December 31,

Risk free interest rate 0.65 % 0.16 %

Expected term (years) 1.75 2.75

Expected dividend yield — % — %

The changes in fair value of the warrant liability for the year ended December 31, 2021 and 2020 were as follows (in thousands):

Warrant Liability

Warrant liability, December 31, 2019 $ 52

Fair value of warrants exercised (94)

Change in fair value of warrants 97

Change in fair value of warrants (15)

Warrant liability, December 31, 2021 $ 40

Deemed Dividend Arising from Warrant Modifications

On January 2, 2020, the Company amended the March 2019 Exercise Agreement warrants to provide for an exercise price of $7.50 per share (subject to adjustment for stock splits and the like). The reduced exercise price of the 63,000 New Warrants increased the fair value of these warrants by approximately $0.1 million during the year ended December 31, 2020, which was recorded as a deemed dividend increasing the net loss attributable to common stockholders and additional paid-in-capital.The expected volatility assumptions are based on the Company's implied volatility. The expected life assumption is based on the remaining contractual terms of the warrants. The risk-free rate is based on the zero coupon rates in effect at the time of valuation. The dividend yield used in the pricing model is zero, because the Company has no present intention to pay cash dividends on its shares of common stock.

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 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 ("GPS Plus") product candidates ("GPS Licensed Products") for all therapeutic and other diagnostic uses in mainland China, Hong Kong, Macau and Taiwan ("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. The Company is responsible for providing the licensed technology and data (the "3DMed License") as well as transferring certain technological and manufacturing know-how (the "transfer of know-how").

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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. The royalties are payable on a GPS Licensed Product-by-GPS Licensed Product and region-by-region basis commencing on the first commercial sale of a GPS Licensed Product in a region and continuing until the latest of (i) the date that is 15 years from the receipt of marketing authorization for such GPS Licensed Product in such region and (ii) the date that is 10 years from the expiration of the last valid claim of a licensed patent covering or claiming such GPS Licensed Product in such region. The royalty rate is subject to reduction under certain circumstances, including when generic competition for a GPS Licensed Product exists in a particular region.

3DMed is responsible for all costs related to developing, obtaining regulatory approval of and commercializing the GPS Licensed Products in the 3DMed Territory. 3DMed is required to use commercially reasonable best efforts to develop and obtain regulatory approval for, and upon receipt of regulatory approval, commercialize the GPS Licensed Products in the 3DMed Territory. A joint development committee has been established between 3DMed and the Company to coordinate and review the development, manufacturing and commercialization plans with respect to the GPS Licensed Products in the 3DMed Territory. The Company and 3DMed also agreed to negotiate in good faith the terms and conditions of a clinical supply agreement, a commercial supply agreement, and related quality agreements pursuant to which the Company will manufacture or have manufactured and supply 3DMed with all quantities of the GPS Licensed Products necessary for 3DMed to develop and commercialize the GPS Licensed Products in the 3DMed Territory until 3DMed has received all approvals required for 3DMed or its designated contract manufacturing organization to manufacture the GPS Licensed Products in the 3DMed Territory.

The 3DMed License Agreement will expire on a GPS Licensed Product-by-GPS Licensed Product and region-by-region basis on the date of the expiration of all of 3DMed’s payment obligations to the Company. Upon expiration of the 3DMed License Agreement, the license granted to 3DMed will become fully paid-up, perpetual and irrevocable. Either party may terminate the 3DMed License Agreement for the other party’s material breach following a cure period or upon certain insolvency events. The Company may terminate the 3DMed License Agreement if 3DMed or its affiliates or sublicensees challenge the validity or enforceability of the licensed patents. At any time following the two-year anniversary of the effective date, 3DMed has the right to terminate the 3DMed License Agreement for convenience, subject to certain requirements. 3DMed may terminate the 3DMed License Agreement upon prior notice to the Company if the grant of the license to 3DMed is prohibited or delayed for a period of time due to a change of U.S. export laws and regulations.

The 3DMed License Agreement includes customary representations and warranties, covenants and indemnification obligations for a transaction of this nature.

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 identified the 3DMed License and the transfer of know-how to be the material promises under the 3DMed License Agreement. The Company determined that 3DMed License and the transfer of know-how are not distinct from each other. As such, for the purposes of ASC 606, the Company determined that these two material promises, described above, should be combined into a single 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

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constrained. The Company achieved $2.0 million of these milestones during the year ended December 31, 2021. The Company determined that $192.5 million in future certain development, regulatory, and sales milestones is variable consideration subject to constraint at inception. At the end of each subsequent reporting period, the Company will reevaluate 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.

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.

Since 3DMed is benefiting from the combined single performance obligation relating to the 3DMed License and the transfer of know-how as the technology transfer occurs, the Company recognized the transaction price over the technology transfer period, which was finalized in the second quarter of 2021. The revenue recognized is based an output method to measure progress, using a straight-line convention, which the Company believes reasonably approximates its efforts in satisfying the combined performance obligation. The Company recognized $7.6 million of license revenue during the year ended December 31, 2021. As of December 31, 2021, the initial transaction price of the single performance obligation of $9.5 million has been fully recognized as licensing revenue.

The following table presents a summary of the activity in the Company's deferred revenue during the year ended December 31, 2021 and 2020 (in thousands):

Deferred revenue, December 31, 2019 $ —

Revenue recognized (1,900)

Revenue recognized (7,600)

Deferred revenue, December 31, 2021 $ —

Cost of Contract Acquisition