Celldex Therapeutics, Inc. (CLDX) FY 2022 MD&A

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

OVERVIEW

We are a biopharmaceutical company dedicated to developing therapeutic monoclonal and bispecific antibodies that address diseases for which available treatments are inadequate. Our drug candidates include antibody-based therapeutics which have the ability to engage the human immune system and/or directly affect critical pathways to improve the lives of patients with inflammatory diseases and many forms of cancer.

We are focusing our efforts and resources on the continued research and development of

Our goal is to build a fully integrated, commercial-stage biopharmaceutical company that develops important therapies for patients with unmet medical needs. We believe our program assets provide us with the strategic options to either retain full economic rights to our innovative therapies or seek favorable economic terms through advantageous commercial partnerships. This approach allows us to maximize the overall value of our technology and product portfolio while best ensuring the expeditious development of each individual product.

The expenditures that will be necessary to execute our business plan are subject to numerous uncertainties. Completion of clinical trials may take several years or more, and the length of time generally varies substantially according to the type, complexity, novelty and intended use of a drug candidate. It is not unusual for the clinical development of these types of drug candidates to each take five years or more, and total development costs could exceed hundreds of millions of dollars for each drug candidate. We estimate that clinical trials of the type we generally conduct are typically completed over the following timelines:

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The duration and the cost of clinical trials may vary significantly over the life of a project as a result of differences arising during the clinical trial protocol, including, among others, the following:

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We test potential drug candidates in numerous preclinical studies for safety, toxicology and immunogenicity. We may then conduct multiple clinical trials for each drug candidate. As we obtain results from trials, we may elect to discontinue or delay clinical trials for certain drug candidates in order to focus our resources on more promising drug candidates.

An element of our business strategy is to pursue the discovery, research and development of a broad portfolio of drug candidates. This is intended to allow us to diversify the risks associated with our research and development expenditures. To the extent we are unable to maintain a broad range of drug candidates, our dependence on the success of one or a few drug candidates increases.

Regulatory approval is required before we can market our drug candidates as therapeutic products. In order to proceed to subsequent clinical trial stages and to ultimately achieve regulatory approval, the regulatory agencies must conclude that our clinical data demonstrate that our product candidates are safe and effective. Historically, the results from preclinical testing and early clinical trials (through Phase 2) have often not been predictive of results obtained in later clinical trials. A number of new drugs and biologics have shown promising results in early clinical trials but subsequently failed to establish sufficient safety and efficacy data to obtain necessary regulatory approvals.

Furthermore, our business strategy includes the option of entering into collaborative arrangements with third parties to complete the development and commercialization of our drug candidates. In the event that third parties take over the clinical trial process for one of our drug candidates, the estimated completion date would largely be under control of that third party rather than us. We cannot forecast with any degree of certainty which proprietary products, if any, will be subject to future collaborative arrangements, in whole or in part, and how such arrangements would affect our development plan or capital requirements. Our programs may also benefit from subsidies, grants, contracts or government or agency-sponsored studies that could reduce our development costs.

As a result of the uncertainties discussed above, among others, it is difficult to accurately estimate the duration and completion costs of our research and development projects or when, if ever, and to what extent we will receive cash inflows from the commercialization and sale of a product. Our inability to complete our research and development projects in a timely manner or our failure to enter into collaborative agreements, when appropriate, could significantly increase our capital requirements and could adversely impact our liquidity. These uncertainties could force us to seek additional, external sources of financing from time to time in order to continue with our business strategy. Our inability to raise additional capital, or to do so on terms reasonably acceptable to us, would jeopardize the future success of our business.

During the past five years through December 31, 2022, we incurred an aggregate of $287.2 million in research and development expenses. The following table indicates the amount incurred for each of our significant research programs and for other identified research and development activities during the years ended December 31, 2022, 2021 and 2020. The amounts disclosed in the following table reflect direct research and development costs, license fees associated with the underlying technology and an allocation of indirect research and development costs to each program.

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Clinical Development Programs

Barzolvolimab (also referred to as CDX-0159)

Barzolvolimab is a humanized monoclonal antibody that specifically binds the receptor tyrosine kinase KIT and potently inhibits its activity. KIT is expressed in a variety of cells, including mast cells, and its activation by its ligand SCF regulates mast cell growth, differentiation, survival, chemotaxis and degranulation. Barzolvolimab is designed to block KIT activation by disrupting both SCF binding and KIT dimerization. We believe that by targeting KIT, barzolvolimab may be able to inhibit mast cell activity and decrease mast cell numbers to provide potential clinical benefit in mast cell related diseases.

In certain inflammatory diseases, such as chronic spontaneous urticaria (CSU), also known as chronic idiopathic urticaria (CIU), and chronic inducible urticaria (CIndU), mast cell degranulation plays a central role in the onset and progression of the disease. In June 2020, we completed a randomized, double-blind, placebo-controlled, single ascending dose escalation Phase 1a study of barzolvolimab in healthy subjects (n = 32; 8 subjects per cohort, 6 barzolvolimab; 2 placebo). Subjects received a single intravenous infusion of barzolvolimab at 0.3, 1.0, 3.0, or 9.0 mg/kg or placebo. The objectives of the study included safety and tolerability, pharmacokinetics (PK) and pharmacodynamics (tryptase and stem cell factor) and immunogenicity. Tryptase is an enzyme synthesized and secreted almost exclusively by mast cells and decreases in plasma tryptase levels are believed to reflect a systemic reduction in mast cell burden in both healthy volunteers and in disease. Data from the study were featured in a late breaking presentation at the European Academy of Allergy and Clinical Immunology (EAACI) Annual Congress 2020 in June. Barzolvolimab demonstrated a favorable safety profile as well as profound and durable reductions of plasma tryptase, consistent with systemic mast cell suppression.

These data supported expansion of the barzolvolimab program into mast cell driven diseases, including initially in CSU and CIndU, diseases where mast cell degranulation plays a central role in the onset and progression of the disease. Phase 1 studies in CSU and CIndU are completing and Phase 2 studies are ongoing. We continue to assess potential opportunities for barzolvolimab in other diseases where mast cells play an important role, such as dermatologic, respiratory, allergic, gastrointestinal and ophthalmic conditions and to this end, are conducting an ongoing Phase 1 study in prurigo nodularis and plan to initiate a Phase 2 study in eosinophilic esophagitis in the first half of 2023. Phase 1 studies of barzolvolimab have been conducted with an intravenous formulation; a subcutaneous formulation has been successfully developed and is being used in Phase 2 studies.

Chronic Spontaneous Urticaria (CSU)

CSU presents as itchy hives, angioedema or both for at least six weeks without a specific trigger; multiple episodes can play out over years or even decades. CSU is one of the most frequent dermatologic diseases with a prevalence of 0.5-1.0% of the total population or up to approximately 1 to 3 million patients in the United States (Weller et al. 2010. Hautarzt. 61(8), Bartlett et al. 2018. DermNet.Org). Approximately 50% of patients with CSU achieve symptomatic control with antihistamines. Omalizumab, an IgE inhibitor, provides relief for roughly half of the remaining antihistamine refractory patients. Consequently, there is a need for additional therapies.

In October 2020, we announced that enrollment had opened and the first patient had been dosed in a Phase 1b multi-center study of barzolvolimab in CSU. This study is a randomized, double-blind, placebo- controlled clinical trial designed to assess the safety of multiple ascending doses of barzolvolimab in up to 40 patients with CSU who remain symptomatic despite treatment with antihistamines. Secondary and exploratory objectives include pharmacokinetic and pharmacodynamic assessments, including measurement of tryptase and stem cell factor levels and clinical activity outcomes (impact on urticaria symptoms, disease control, clinical response) as well as quality of life assessments. Barzolvolimab is administered intravenously (0.5, 1.5, 3 and 4.5 mg/kg at varying dosing schedules) as add on treatment to H1- antihistamines, either alone or in combination with H2-antihistamines and/or leukotriene receptor agonists.

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In February 2023, we reported positive interim data from the CSU study. As of the data cut-off date on November 29, 2022, enrollment was complete with 45 patients with moderate to severe CSU refractory to antihistamines enrolled and treated [35 barzolvolimab (n=9 in 0.5 mg/kg; n=8 in 1.5 mg/kg; n=9 in 3.0 mg/kg; n=9 in 4.5 mg/kg) and 10 placebo]. The 0.5 mg/kg, 1.5 mg/kg and 3.0 mg/kg cohorts had completed study participation through 24 weeks; 6 of 9 patients in the 4.5 mg/kg cohort had completed through the week 20 visit. Complete data were included for all patients in dose levels through 3.0 mg/kg through 24 weeks. All available data for the 4.5 mg/kg and placebo dose levels were presented for adverse events. Activity data for the 4.5 mg/kg dose level were reported through week 20. Activity data for the 0.5 mg/kg and placebo group were only included through week 12 because, as expected, most patients from these groups had significant symptoms ahead of week 24 and discontinued follow up. Two patients did not receive all doses of study treatment [4.5 mg/kg (1), placebo (1)].

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In June 2022, we announced that the first patient has been dosed in a Phase 2 study in patients with CSU who remain symptomatic despite antihistamine therapy. The study is being conducted at approximately 75 sites across 9 countries. The study is a randomized, double-blind, placebo-controlled, parallel group Phase 2 study evaluating the efficacy and safety profile of multiple dose regimens of barzolvolimab to determine the optimal dosing strategy. Approximately 168 patients will be randomly assigned on a 1:1:1:1 ratio to receive subcutaneous injections of barzolvolimab at 75 mg every 4 weeks, 150 mg every 4 weeks, 300 mg every 8 weeks or placebo during a 16-week placebo-controlled treatment phase. Patients will then enter a 36-week active treatment phase, in which patients not already randomized to barzolvolimab at 150 mg every 4 weeks or 300 mg every 8 weeks will be randomized 1:1 to receive one of these two dose regimens; patients already randomized to these treatment arms will remain on the same regimen as during the placebo-controlled treatment phase. Following the treatment period, patients will enter a 24-week follow up phase. The primary endpoint of the study is mean change in baseline to week 12 in UAS7 (Urticaria Activity Score over 7 days). Secondary endpoints include safety and other assessments of clinical activity including ISS7 (Itch Severity Score over 7 days), HSS7 (Hive Severity Score over 7 days) and AAS7 (Angioedema Activity Score over 7 days). Based on current enrollment projections, we anticipate that enrollment to this study will be completed by the end of the third quarter of 2023 and we plan to report topline data either late this year or in the first quarter of 2024.

Chronic Inducible Urticaria (CIndU)

CIndUs are forms of urticaria that have an attributable cause or trigger associated with them, typically resulting in hives or wheals. The prevalence of CIndU is estimated at 0.5% of the total population and is reported to overlap in up to 36% of CSU patients (Weller et al. 2010. Hautarzt. 61(8), Bartlett et al. 2018. DermNet.Org). There are currently no approved therapies for chronic inducible urticarias other than antihistamines and patients attempt to manage symptoms associated with their disease through avoidance of triggers. We are exploring cold-induced, dermographism (scratch-induced) and cholinergic (exercise-induced) urticarias.

In December 2020, we announced that enrollment had opened and the first patient had been dosed in a Phase 1b study in CIndU being conducted in Germany in patients who are refractory to antihistamines. This study is an open label clinical trial designed to evaluate the safety of a single dose (3 mg/kg) of barzolvolimab in patients with cold urticaria (ColdU) or symptomatic dermographism (SD). In March and June 2021, respectively, we added a third cohort (single dose, 3 mg/kg) in patients with cholinergic urticaria and a fourth cohort at a lower dose (single dose, 1.5 mg/kg) in ColdU. Patient’s symptoms are induced via provocation testing that resembles real life triggering situations. Secondary and exploratory objectives include pharmacokinetic and pharmacodynamic assessments, including changes from baseline provocation thresholds, measurement of tryptase and stem cell factor levels, clinical activity outcomes (impact on urticaria symptoms, disease control, clinical response), quality of life assessments and measurement of tissue mast cells through skin biopsies. Barzolvolimab is administered intravenously on Day 1 as add on treatment to H1-antihistamines.

In November 2022, data from the ColdU and SD cohorts treated with a single intravenous infusion of barzolvolimab at 3 mg/kg were published in Allergy (Terhorst-Molawi et al Allergy. 2022 Nov 16. doi: 10.1111/all.15585). Safety results were reported for 21 patients; activity results were reported for the 20 patients who received a full dose of barzolvolimab. Patients had high disease activity. At baseline, patients’ mean scores (range) for Dermatology Life Quality Index (DLQI) [10.8 (2–21)] and Urticaria Control Test (UCT) [6.0 (0–13)] indicated marked impairment of quality of life (QoL) and poorly controlled disease, respectively. Three patients (1 with ColdU and 2 with SD) were previously treated with omalizumab and chose to discontinue that treatment because they remained symptomatic. At baseline, provocation thresholds, on average (range), were 18.9°C or 66°F (5–27°C or 41–80.6°F) for patients with ColdU and 3.5 (2–4) pins for patients with SD.

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In December 2022, we presented long term follow up data from the 3.0 mg/kg cohorts in cold urticaria and symptomatic dermographism at the GA²LEN Global Urticaria Forum (GUF) 2022. 14 patients consented to the optional long term follow up evaluation (6 cold, 8 symptomatic dermographism); 10 of the 14 still had complete control of their disease as assessed by provocation testing at week 12. Data were collected at one or more timepoints beyond week 12 through week 36.

In December 2022, we also presented 12 week treatment results for the 1.5 mg/kg cohort in cold urticaria at the GA²LEN Global Urticaria Forum (GUF) 2022. 10 patients received a single intravenous infusion of barzolvolimab at 1.5 mg/kg. Patients had high disease activity as assessed by provocation threshold testing with a mean baseline critical temperature threshold of 18.4°C or 65°F with a range from 6 to 27°C or 43 to 81°F. All patients had disease refractory to antihistamines and five patients had disease refractory to omalizumab. Safety results were reported for all 10 patients; activity results were reported for the 9 patients who received a full dose of barzolvolimab, including four patients with omalizumab refractory disease.

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To date, 19 of 19 (100%) patients with cold urticaria treated with either a single dose of barzolvolimab at 1.5 or 3.0 mg/kg in this Phase 1b study have experienced a complete response by provocation testing, including 5 patients with omalizumab refractory disease.

In July 2022 we announced that the first patient has been dosed in a Phase 2 study in patients with CIndU who remain symptomatic despite antihistamine therapy. The study will be conducted at approximately 85 sites across approximately 12 countries. The randomized, double-blind, placebo-controlled, parallel group Phase 2 study is evaluating the efficacy and safety profile of multiple dose regimens of barzolvolimab in patients with CIndU to determine the optimal dosing strategy. Approximately 180 patients in 2 cohorts (differentiated by CIndU subtype) including 90 patients with cold urticaria and 90 patients with symptomatic dermographism will be randomly assigned on a 1:1:1 ratio to receive subcutaneous injections of barzolvolimab at 150 mg every 4 weeks, 300 mg every 8 weeks or placebo during a 20-week treatment phase. Patients will then enter a follow-up phase for an additional 24 weeks. In addition, the study includes the option for patients who have symptoms following the treatment phase, including patients who were on placebo, to enroll in an open label extension where all patients receive 300 mg every 9 weeks of barzolvolimab. The primary endpoint of the study is the percentage of patients with a negative provocation test at week 12 (using TempTest(R) and FricTest(R)). Secondary endpoints include safety and other assessments of clinical activity including CTT (Critical Temperature Threshold), CFT (Critical Friction Threshold) and WI-NRS (Worst itch numeric rating scale).

Prurigo Nodularis (PN)

We have expanded clinical development of barzolvolimab into prurigo nodularis (PN). PN is a chronic skin disease characterized by the development of hard, intensely itchy (pruritic) nodules on the skin. Mast cells through their interactions with sensory neurons and other immune cells are believed to play an important role in amplifying chronic itch and neuroinflammation, both of which are a hallmark of PN. There is currently only one FDA approved therapy for PN, representing an area of significant unmet need. Industry sources estimate there are approximately 154,000 patients in the United States with PN who have undergone treatment within the last 12 months and, of these, approximately 75,000 would be biologic-eligible. In December 2021, the first patient was dosed in a Phase 1b multi-center, randomized, double-blind, placebo-controlled intravenous study designed to assess the safety and treatment effects across multiple dosing cohorts of barzolvolimab in up to 30 patients with PN. Enrolling an intravenous, early stage study in the dermatology setting has been a challenge and the study has taken longer than expected to complete. In February 2023, we closed enrollment at 24 patients, which we believe will provide sufficient data for analysis to inform future development decisions in PN. Following the completion of the 24 week follow up period post dosing for patients on study, we plan to present data from the study in the second half of 2023. Potential future development in PN will utilize the subcutaneous formulation of barzolvolimab.

Eosinophilic Esophagitis (EoE)

In February 2022, we announced that we will be expanding clinical development of barzolvolimab into eosinophilic esophagitis (EoE), the most common type of eosinophilic gastrointestinal disease. EoE is a chronic inflammatory disease of the esophagus characterized by the infiltration of eosinophils. This chronic inflammation can result in trouble swallowing, chest pain, vomiting and impaction of food in the esophagus, a medical emergency. Several studies have suggested that mast cells may be an important driver in the disease, demonstrating that the number and activation state of mast cells are greatly increased in EoE biopsies and that mast cell signatures correlate with markers of inflammation, fibrosis, pain and disease severity. Currently, there is only one FDA approved therapy for EoE, representing an area of significant unmet need. Industry sources estimate there are approximately 160,000 patients in the United States with EoE who have undergone treatment within the last 12 months and, of these, approximately 48,000 would be biologic-eligible. Given the lack of effective therapies for EoE and barzolvolimab’s potential as a mast cell depleting agent, we believe EoE is an important indication for future study and plan to initiate a Phase 2 multi-center, randomized, double-blind, placebo-controlled subcutaneous study designed to assess the treatment effects and safety of barzolvolimab in patients with EoE in the first half of 2023.

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Additional Barzolvolimab Development Activities

Manufacturing activities to support the introduction of the barzolvolimab subcutaneous formulation into the clinical program have been completed and, in September 2021, we initiated dosing in a randomized, double-blind, placebo-controlled, Phase 1 study designed to evaluate the safety of single ascending doses of the subcutaneous formulation of barzolvolimab in healthy volunteers. In February 2022, we reported that subcutaneous administration of barzolvolimab was well tolerated and that multiple dose levels have been identified that possess promising pharmacokinetic and pharmacodynamic properties. Importantly, subcutaneous delivery of barzolvolimab resulted in dose-dependent, rapid and sustained decreases in serum tryptase compared with placebo and achieved sufficient exposure to produce tryptase suppression levels comparable with the levels that generated impressive clinical activity observed in the Phase 1 CIndU intravenous study. The Phase 2 multi-dose studies in urticaria are designed to evaluate 75 mg and 150 mg administered every 4 weeks and 300 mg administered every 8 weeks. These doses support a 0.5 to 2 ml injection volume, allowing for a single injection as barzolvolimab advances towards potential commercialization. In 2022, we initiated transfer of our current barzolvolimab manufacturing process to a contract manufacturing organization to support late-stage trials and to prepare for potential commercialization.

In February 2022, we reported interim data after completing the in-life dosing portion of our six-month chronic toxicology study in non-human primates. The only clinically adverse finding at the completion of dosing was a profound impact on spermatogenesis, an expected and well understood effect of KIT inhibition. As a standard part of toxicology studies, some animals from each group continued to be observed through a recovery period to understand the reversibility of any adverse findings. Due to the very high concentrations of barzolvolimab at the end of dosing, the recovery period was approximately one year. As we expected, and consistent with previous findings with KIT blocking antibodies, we were pleased to report in December 2022, that during this recovery period spermatogenesis fully recovered in all male animals as measured by both sperm count and motility. We expect the final histologic analysis and study report in early 2023. We are encouraged with these findings and believe these data strongly support our Phase 2 studies in urticaria and in future indications.

Bispecific Platform

Our next generation bispecific antibody platform is supporting the expansion of our pipeline with additional candidates for inflammatory diseases and oncology. Targets are being selected based on new science as well as their compatibility to be used in bispecific antibody formats with our existing antibody programs. Development is focused on emerging, important pathways controlling inflammatory diseases or immunity to tumors.

CDX-585

CDX-585 combines our proprietary highly active PD-1 blockade and anti-ILT4 blockade to prevent immunosuppressive signals in T cells and myeloid cells, respectively. ILT4 is emerging as an important immune checkpoint on myeloid cells and is thought to contribute to resistance to PD-1 blockade. Interactions of PD-1 and ILT4 with their ligands are known to deliver immune suppressive signals that can attenuate anti-tumor immune responses. The concept behind CDX-585 is to simultaneously inhibit both T cell and myeloid suppressive signals to potentiate the anti-tumor activity of both cell types, and potentially overcome PD-1 resistance. In preclinical studies, CDX-585 was demonstrated to be a potent inhibitor of PD-1 signaling in comparison to the approved PD-1 antibody, nivolumab. In addition, CDX-585 activated and promoted a strong inflammatory phenotype in human macrophage and dendritic cell cultures. Together these activities of CDX-585 enhanced the response in a mixed lymphocyte reaction assay above that observed for either parental mAb or the combination of the PD-1 and ILT4 mAbs. The in vivo efficacy of CDX-585 was also demonstrated in a melanoma humanized mouse model. CDX-585 has successfully completed GMP manufacturing and IND-enabling studies to support clinical development. CDX-585 will initially be developed for the treatment of solid tumors either as monotherapy or in combination with other oncologic treatments and is expected to enter the clinic in 2023 in patients with advanced malignancies.

CDX-527

CDX-527 used our proprietary highly active anti-PD-L1 and CD27 human antibodies to couple CD27 co-stimulation with blockade of the PD-L1/PD-1 pathway to help prime and activate anti-tumor T cell responses through CD27 co-stimulation, while preventing PD-1 inhibitory signals that subvert the immune response. In the summer of 2020, we initiated a Phase 1 dose-escalation study in patients with advanced or metastatic solid tumors that had progressed during or after standard of care therapy to be followed by tumor-specific expansion cohorts. Enrollment to the dose escalation portion was successfully completed and an expansion cohort in patients with checkpoint naïve ovarian cancer was initiated. In November 2022, we provided an update on the study. With multiple

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clinical trials actively recruiting in ovarian cancer, enrollment to the expansion cohort did not meet our internal timelines and a review of the results did not meet internal hurdles for proceeding and we closed enrollment to the study and discontinued the program.

Other programs:

CDX-1140

CDX-1140 is a fully human agonist monoclonal antibody targeted to CD40, a key activator of immune response, which is found on dendritic cells, macrophages and B cells and is also expressed on many cancer cells. A Phase 1 study was conducted in patients with recurrent, locally advanced or metastatic solid tumors and B cell lymphomas. An MTD of 1.5 mg/kg was established and clinical activity was observed both as a monotherapy and in combination with pembrolizumab. Despite evidence of clinical benefit, questions remain to be answered about CDX-1140, and the broader CD40 agonist class, regarding the best clinical settings, regimens, and possible combinations before advancing into additional Celldex-sponsored studies. Given our pipeline priorities and resource requirements, in August of 2022, we announced that we are not progressing further Company-sponsored studies at this time and are exploring these questions in third-party sponsored studies.

CRITICAL ACCOUNTING POLICIES AND ESTIMATES

Our significant accounting policies are described in Note 2 to the financial statements included in Item 8 of this Form 10-K. We believe our most critical accounting policies include accounting for contingent consideration, revenue recognition, intangible and long-lived assets, research and development expenses and stock-based compensation expense.

The methods, estimates and judgments we use in applying our most critical accounting policies have a significant impact on the results we report in our financial statements. We evaluate our estimates and judgments on an ongoing basis. We base our estimates on historical experience and on assumptions that we believe to be reasonable under the circumstances. Our experience and assumptions form the basis for our judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results may vary from what we anticipate and different assumptions or estimates about the future could materially change our reported results. We believe the following accounting policies are the most critical to us in that they are important to the portrayal of our financial statements and they require our most difficult, subjective or complex judgments in the preparation of our financial statements:

Contingent Consideration

We record contingent consideration resulting from a business combination at its fair value on the acquisition date. We determine the fair value of the contingent consideration based primarily on the following factors:

Our contingent consideration arose in connection with our acquisition of Kolltan. On a quarterly basis, we revalue these obligations and record increases or decreases in their fair value as an adjustment to operating earnings. As of December 31, 2022, the fair value of our contingent consideration was $0.0 million. Changes to contingent consideration obligations can result from adjustments to discount rates, accretion of the discount rates due to the passage of time, changes in our estimates of the likelihood or timing of achieving development or commercial milestones, changes in the probability of certain clinical events or changes in the assumed probability associated with regulatory approval.

The assumptions related to determining the value of contingent consideration include a significant amount of judgment, and any changes in the underlying estimates could have a material impact on the amount of contingent consideration adjustment recorded in any given period.

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Revenue Recognition

Revenues are recognized when performance obligations under agreements or contracts are satisfied, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those services.

The Company determines revenue recognition through the following steps:

Revenue for the Company is derived from product development agreements with collaborative partners for the research and development of therapeutic drug candidates. The terms of the agreements may include nonrefundable signing and licensing fees, funding for research, development and manufacturing, milestone payments and royalties on any product sales derived from collaborations. The Company assesses the multiple obligations typically within product development contracts to determine the distinct performance obligations and how to allocate the arrangement consideration to each distinct performance obligation. Under product development agreements, revenue is generally recognized using a cost-to-cost measure of progress. Revenue is recognized based on the costs incurred to date as a percentage of the total estimated costs to fulfill the contract. Incurred cost represents work performed, which corresponds with, and thereby best depicts, the transfer of control to the customer. Due to the nature of the work performed in these arrangements, the estimation of cost at completion is complex, subject to many variables, such as expected clinical trial costs, and requires significant judgements. Circumstances can arise that change original estimates of costs or progress toward completion. Any revisions to estimates are reflected in revenue on a cumulative catch-up basis in the period in which the change in circumstances became known.

Revenue for the Company is also derived from manufacturing and research and development arrangements. The Company owns and operates a cGMP manufacturing facility in Fall River, Massachusetts, to produce drug substance for its current and planned early-stage clinical trials. In order to utilize excess capacity, the Company has, from time to time, entered into contract manufacturing and research and development arrangements in which services are provided on a time-and-material basis or at a negotiated fixed- price. Revenue from time-and-material contracts is generally recognized on an output basis as labor hours and/or direct expenses are incurred. Under fixed-price contracts, revenue is generally recognized on an output basis as progress is made toward completion of the performance obligations using surveys of performance completed to date.

Intangible and Long-Lived Assets

We evaluate the recoverability of our long-lived assets, including property and equipment when circumstances indicate that an event of impairment may have occurred. Determination of recoverability is based on an estimate of undiscounted future cash flows resulting from the use of the asset and its eventual disposition. In the event that such cash flows are not expected to be sufficient to recover the carrying amount of the assets, the assets are written down to their estimated fair values.

IPR&D assets acquired in a business combination initially are recorded at fair value and accounted for as indefinite-lived intangible assets. These assets are capitalized on our balance sheets until either the project underlying them is completed or the assets become impaired. If a project is completed, the carrying value of the related intangible asset is amortized over the remaining estimated life of the asset beginning in the period in which the project is completed. If a project becomes impaired or is abandoned, the carrying value of the related intangible asset is written down to its fair value and an impairment charge is taken in the period in which the impairment occurs. Discounted cash flow models are typically used in these tests, and the models require the use of significant estimates and assumptions including but not limited to:

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Each IPR&D asset is assessed for impairment at least annually or when impairment indicators are present. The Company has the option to assess qualitative factors to determine if it is more likely than not that the IPR&D asset is impaired and whether it is necessary to perform a quantitative impairment test.

Research and Development Expenses

Research and development costs, including internal and contract research costs, are expensed as incurred. Research and development expenses consist mainly of clinical trial costs, manufacturing of clinical material, toxicology and other preclinical studies, personnel costs, depreciation, license fees and funding of outside contracted research.

Clinical trial expenses include expenses associated with clinical research organization, or CRO, services. Contract manufacturing expenses include expenses associated with contract manufacturing organization, or CMO, services. The invoicing from CROs and CMOs for services rendered can lag several months. We accrue the cost of services rendered in connection with CRO and CMO activities based on our estimate of costs incurred. We maintain regular communication with our CROs and CMOs to assess the reasonableness of our estimates. Differences between actual expenses and estimated expenses recorded have not been material and are adjusted for in the period in which they become known.

Stock-Based Compensation Expense

We record stock-based compensation expense for all stock-based awards made to employees, consultants and non-employee directors based on the estimated fair values of the stock-based awards expected to vest at the grant date and adjust, if necessary, to reflect actual forfeitures. Our estimates of employee, consultant, and non-employ director stock option values rely on estimates of future uncertain events. Significant assumptions include the use of historical volatility to estimate the expected stock price volatility. We also estimate expected term based on historical exercise patterns. For consultant and non-employee director grants, we may elect to use the contractual term as the expected term in the option-pricing model. Actual volatility and lives of options may be significantly different from our estimates. Compensation expense for all stock-based awards is recognized using the straight-line method over the term of vesting or performance.

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RESULTS OF OPERATIONS

Year Ended December 31, 2022 compared with Year Ended December 31, 2021

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Net Loss

The $41.8 million increase in net loss for the year ended December 31, 2022, as compared to the year ended December 31, 2021, was primarily due to the $15.0 million litigation settlement related loss recorded in the second quarter of 2022 and increases in research and development and general and administrative expenses, partially offset by an increase in the gain on fair value remeasurement of contingent consideration.

Revenue

Product development and licensing agreements revenue for the year ended December 31, 2022, was relatively consistent with the year ended December 31, 2021. The $2.3 million decrease in contracts and grants revenue for the year ended December 31, 2022, as compared to the year ended December 31, 2021, was primarily related to a decrease in services performed under our manufacturing and research and development agreements with Rockefeller University and Gilead Sciences. We expect revenue to increase over the next twelve months as a result of an increase in services expected to be performed under our manufacturing and research and development agreement with Rockefeller University.

Research and Development Expense

Research and development expenses consist primarily of (i) personnel expenses, (ii) laboratory supply expenses relating to the development of our technology, (iii) facility expenses and (iv) product development expenses associated with our drug candidates as follows:

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Personnel expenses primarily include salary, benefits, stock-based compensation and payroll taxes. The $6.3 million increase in personnel expenses for the year ended December 31, 2022, as compared to the year ended December 31, 2021, was primarily due to higher stock-based compensation expense and an increase in employee headcount. We expect personnel expenses to increase over the next twelve months as a result of additional headcount to support the expanded development of barzolvolimab.

Laboratory supplies expenses include laboratory materials and supplies, services, and other related expenses incurred in the development of our technology. The $0.3 million increase in laboratory supply expenses for the year ended December 31, 2022, as compared to the year ended December 31, 2021, was primarily due to higher laboratory services, materials and supplies purchases. We expect laboratory supplies expenses to remain relatively consistent over the next twelve months, although there may be fluctuations on a quarterly basis.

Facility expenses include depreciation, amortization, utilities, rent, maintenance and other related expenses incurred at our facilities. Facility expenses for the year ended December 31, 2022 were relatively consistent with the year ended December 31, 2021. We expect facility expenses to remain relatively consistent over the next twelve months, although there may be fluctuations on a quarterly basis.

Product development expenses include clinical investigator site fees, external trial monitoring costs, data accumulation costs, contracted research and outside clinical drug product manufacturing. The $19.9 million increase in product development expenses for the year ended December 31, 2022, as compared to the year ended December 31, 2021, was primarily due to an increase in barzolvolimab clinical trial and contract manufacturing expenses. We expect product development expenses to increase over the next twelve months as a result of further increases in barzolvolimab clinical trial and contract manufacturing expenses.

General and Administrative Expense

The $6.7 million increase in general and administrative expenses for the year ended December 31, 2022, as compared to the year ended December 31, 2021, was primarily due to higher stock-based compensation, legal and barzolvolimab commercial planning expenses. We expect general and administrative expenses to remain relatively consistent over the next twelve months, although there may be fluctuations on a quarterly basis.

Intangible Asset Impairment

During the third quarter of 2021, we evaluated the TAM program IPR&D asset for potential impairment as a result of a lack of interest in the program from third parties. We concluded that the TAM program IPR&D asset was fully impaired, and a non-cash impairment charge of $3.5 million was recorded in the third quarter of 2021.

Gain on Fair Value Remeasurement of Contingent Consideration

The $6.9 million gain on fair value remeasurement of contingent consideration for the year ended December 31, 2022 was primarily due to our decision to deprioritize the CDX-1140 program.

Litigation Settlement Related Loss

We recorded a loss of $15.0 million in the second quarter of 2022 related to the Initial Payment due under the binding settlement term sheet (the “Term Sheet”) entered with SRS.

Investment and Other Income, Net

The $2.4 million increase in investment and other income, net for the year ended December 31, 2022, as compared to the year ended December 31, 2021, was primarily due to higher interest rates on fixed income investments. We expect investment and other income to increase over the next twelve months primarily due to higher interest rates and higher other income related to our sale of New Jersey tax benefits.

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Income Tax Benefit

A $0.2 million non-cash income tax benefit was recorded for the year ended December 31, 2021 related to the impairment of the TAM program IPR&D asset in the third quarter of 2021.

Year Ended December 31, 2021 compared with Year Ended December 31, 2020

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Net Loss

The $10.7 million increase in net loss for the year ended December 31, 2021, as compared to the year ended December 31, 2020, was primarily the result of an increase in research and development and general and administrative expenses, a decrease in the gain on fair value remeasurement of contingent consideration and revenue, partially offset by a decrease in non-cash intangible asset impairment expense.

Revenue

The Company’s agreement with Rockefeller University, as amended, (the “Rockefeller Agreement”) provides for the Company to perform manufacturing and development services for Rockefeller University for their portfolio of antibodies against HIV. This portfolio was licensed to Gilead Sciences in January 2020 from Rockefeller University (“Rockefeller Transaction”). The $2.3 million decrease in revenue from product development and licensing agreements for the year ended December 31, 2021, as compared to the year ended December 31, 2020, was primarily due to the $1.8 million received from the Rockefeller Transaction in the first quarter of 2020. The $0.5 million decrease in revenue from contracts and grants for the year ended December 31, 2021, as compared to the year ended December 31, 2020, was primarily related to a decrease in services performed under our contract manufacturing and research and development agreements with Rockefeller University and Gilead Sciences.

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Research and Development Expense

Research and development expenses consist primarily of (i) personnel expenses, (ii) laboratory supply expenses relating to the development of our technology, (iii) facility expenses and (iv) product development expenses associated with our drug candidates as follows:

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Personnel expenses primarily include salary, benefits, stock-based compensation and payroll taxes. The $4.5 million increase in personnel expenses for the year ended December 31, 2021, as compared to the year ended December 31, 2020, was primarily due to higher stock-based compensation expense and an increase in employee headcount.

Laboratory supplies expenses include laboratory materials and supplies, services, and other related expenses incurred in the development of our technology. The $1.6 million increase in laboratory supply expenses for the year ended December 31, 2021, as compared to the year ended December 31, 2020, was primarily due to higher laboratory materials and supplies purchases.

Facility expenses include depreciation, amortization, utilities, rent, maintenance and other related expenses incurred at our facilities. The $1.6 million decrease in facility expenses for the year ended December 31, 2021, as compared to the year ended December 31, 2020, was primarily due to lower rent as a result of the consolidation of our Massachusetts lab and manufacturing facilities in the second quarter of 2020 and lower depreciation expenses.

Product development expenses include clinical investigator site fees, external trial monitoring costs, data accumulation costs, contracted research and outside clinical drug product manufacturing. The $6.0 million increase in product development expenses for the year ended December 31, 2021, as compared to the year ended December 31, 2020, was primarily due to an increase in barzolvolimab clinical trial and contract research expenses.

General and Administrative Expense

The $6.0 million increase in general and administrative expenses for the year ended December 31, 2021, as compared to the year ended December 31, 2020, was primarily due to higher stock-based compensation and legal expenses.

Intangible Asset Impairment

We evaluated the TAM program IPR&D asset for potential impairment in the fourth quarter of 2020 as a result of our decision to focus our efforts on out-licensing opportunities for the program, which caused changes in projected development and regulatory timelines related to the program. We concluded that the TAM program IPR&D asset was partially impaired, and a non-cash impairment charge of $14.5 million was recorded in the fourth quarter of 2020. During the third quarter of 2021, we evaluated the TAM program IPR&D asset for potential impairment as a result of a lack of interest in the program from third parties. We concluded that the TAM program IPR&D asset was fully impaired, and a non-cash impairment charge of $3.5 million was recorded in the third quarter of 2021. We evaluated the CDX-3379 IPR&D asset for potential impairment as a result of the discontinuation of the CDX-3379 program in the second quarter of 2020. We concluded that the CDX-3379 IPR&D asset was fully impaired, and a non-cash impairment charge of $3.5 million was recorded in the second quarter of 2020.

Gain on Fair Value Remeasurement of Contingent Consideration

The $1.4 million gain on fair value remeasurement of contingent consideration for the year ended December 31, 2021 was primarily due to updated assumptions for the TAM program, partially offset by losses related to changes in discount rates and the passage of time.

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Investment and Other Income, Net

The $1.9 million decrease in investment and other income, net for the year ended December 31, 2021, as compared to the year ended December 31, 2020, was primarily due to lower other income related to our sale of New Jersey tax benefits.

Income Tax Benefit

A $0.2 million non-cash income tax benefit was recorded for the year ended December 31, 2021 related to the impairment of the TAM program IPR&D asset in the third quarter of 2021.

LIQUIDITY AND CAPITAL RESOURCES

Our cash equivalents are highly liquid investments with a maturity of three months or less at the date of purchase and consist primarily of investments in money market mutual funds with commercial banks and financial institutions. We maintain cash balances with financial institutions in excess of insured limits. We do not anticipate any losses with respect to such cash balances. We invest our excess cash balances in marketable securities, including municipal bond securities, U.S. government agency securities and high- grade corporate bonds that meet high credit quality standards, as specified in our investment policy. Our investment policy seeks to manage these assets to achieve our goals of preserving principal and maintaining adequate liquidity.

The use of our cash flows for operations has primarily consisted of salaries and wages for our employees; facility and facility-related costs for our offices, laboratories and manufacturing facility; fees paid in connection with preclinical studies, clinical studies, contract manufacturing, laboratory supplies and services; and consulting, legal and other professional fees. We anticipate that our cash flows from operations will continue to be focused in these areas as we progress our current drug candidates through the clinical trial process and develop additional drug candidates. To date, the primary sources of cash flows from operations have been payments received from our collaborative partners and from government entities and payments received for contract manufacturing and research and development services provided by us. The timing of any new contract manufacturing and research and development agreements, collaboration agreements, government contracts or grants and any payments under these agreements, contracts or grants cannot be easily predicted and may vary significantly from quarter to quarter.

At December 31, 2022, our principal sources of liquidity consisted of cash, cash equivalents and marketable securities of $305.0 million. We have had recurring losses and incurred a loss of $112.3 million for the year ended December 31, 2022. Net cash used in operations for the year ended December 31, 2022 was $103.7 million. We believe that the cash, cash equivalents and marketable securities at December 31, 2022 are sufficient to meet estimated working capital requirements and fund planned operations through 2025, which include our ongoing Phase 1b studies in urticaria and prurigo nodularis and our ongoing and planned Phase 2 studies in CSU, CIndU and EoE. This could be impacted if we elect to pay the future milestones under the Settlement Agreement with SRS, if any, in cash.

During the next twelve months, we may take further steps to raise additional capital to meet our long-term liquidity needs including, but not limited to, one or more of the following: the licensing of drug candidates with existing or new collaborative partners, possible business combinations, issuance of debt, or the issuance of common stock or other securities via private placements or public offerings. Although we have been successful in raising capital in the past, there can be no assurance that additional financing will be available on acceptable terms, if at all, and our negotiating position in capital raising efforts may worsen as existing resources are used. There is also no assurance that we will be able to enter into further collaborative relationships. Additional equity financings may be dilutive to our stockholders; debt financing, if available, may involve significant cash payment obligations and covenants that restrict our ability to operate as a business; and licensing or strategic collaborations may result in royalties or other terms which reduce our economic potential from products under development. Our ability to continue funding our planned operations into and beyond twelve months from the issuance date is also dependent on the timing and manner of payment of the future milestones under the Settlement Agreement with SRS, in the event that we achieve the milestones related to those payments. We may decide to pay those milestone payments in cash, shares of our common stock or a combination thereof. If we are unable to raise the funds necessary to meet our long-term liquidity needs, we may have to delay or discontinue the development of one or more programs, discontinue or delay ongoing or anticipated clinical trials, discontinue or delay our commercial manufacturing efforts, discontinue or delay our efforts to expand into additional indications for our drug product candidates, license out programs earlier than expected, raise funds at a significant discount or on other unfavorable terms, if at all, or sell all or a part of our business.

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Operating Activities

Net cash used in operating activities was $103.7 million for the year ended December 31, 2022 compared to $60.9 million for the year ended December 31, 2021. The increase in net cash used in operating activities was primarily due to increases in research and development and general and administrative expenses and the $15.0 million Initial Payment made to SRS under the Settlement Agreement. We expect that cash used in operating activities (not including the $15.0 million Initial Payment made to SRS) will increase over the next twelve months as a result of the expanded development of barzolvolimab.

Net cash used in operating activities was $60.9 million for the year ended December 31, 2021 compared to $40.4 million for the year ended December 31, 2020. The increase in net cash used in operating activities was primarily due to increases in research and development and general and administrative expenses and a decrease in revenue.

We have incurred and will continue to incur significant costs in the area of research and development, including preclinical and clinical trials and clinical drug product manufacturing as our drug candidates are developed. We plan to spend significant amounts to progress our current drug candidates through the clinical trial processes as well as to develop additional drug candidates. As our drug candidates progress through the clinical trial process, we may be obligated to make significant milestone payments, pursuant to our existing arrangements and arrangements we may enter in the future.

Investing Activities

Net cash provided by investing activities was $89.9 million for the year ended December 31, 2022 compared to net cash used in investing activities of $216.2 million for the year ended December 31, 2021. The increase in net cash provided by investing activities was primarily due to net sales and maturities of marketable securities of $91.7 million for the year ended December 31, 2022 as compared to net purchases of $214.9 million for the year ended December 31, 2021. We expect that cash provided by investing activities will increase over the next twelve months as we fund our operations through the combination of net proceeds from the sales and maturities of marketable securities, cash provided by financing activities and/or new partnerships, although there may be significant fluctuations on a quarterly basis based on the amount of cash provided by financing activities and/or new partnerships.

Net cash used in investing activities was $216.2 million for the year ended December 31, 2021 compared to $98.2 million for the year ended December 31, 2020. The increase in net cash used in investing activities was primarily due to net purchases of marketable securities for the year ended December 31, 2021 of $214.9 million as compared to $96.7 million for the year ended December 31, 2020.

Financing Activities

Net cash provided by financing activities was $4.1 million for the year ended December 31, 2022 compared to $272.4 million for the year ended December 31, 2021. The decrease in net cash provided by financing activities was primarily due to a decrease in net proceeds from stock issuances.

Net cash provided by financing activities was $272.4 million for the year ended December 31, 2021 compared to $171.2 million for the year ended December 31, 2020. The increase in net cash provided by financing activities was primarily due to an increase in net proceeds from stock issuances.

Equity Offerings

In November 2020, we filed an automatic shelf registration statement with the SEC to register for sale any combination of the types of securities described in the shelf registration statement.

In May 2016, we entered into a controlled equity offering sales agreement with Cantor Fitzgerald & Co. (“Cantor”) to allow us to issue and sell shares of our common stock from time to time through Cantor, acting as agent. During the year ended December 31, 2020, we issued 7,125,004 million shares of common stock under the agreement with Cantor resulting in net proceeds of $29.4 million, after deducting commission and offering expenses. No shares of common stock were sold under the Cantor Agreement during the years ended December 31, 2021 and December 31, 2022. At December 31, 2022, we had $50.0 million remaining in aggregate gross offering price available under our November 2020 prospectus supplement.

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During the second quarter of 2020, the Company issued 15,384,614 shares of its common stock in an underwritten public offering resulting in net proceeds to the Company of $141.4 million, after deducting underwriting fees and offering expenses.

During the third quarter of 2021, we issued 6,845,238 shares of common stock in an underwritten public offering resulting in net proceeds of $269.9 million, after deducting underwriting fees and offering expenses.

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