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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

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FORM 10-K

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(Mark one)

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For the fiscal year ended December 31, 20212022

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or

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Commission File Number 000-15006

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CELLDEX THERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)

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Perryville III Building, 53 Frontage Road, Suite 220, Hampton, New Jersey 08827

(Address of principal executive offices) (Zip Code)

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Registrant’s telephone number, including area code: (908) 200-7500

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Securities registered pursuant to Section 12(b) of the Act:

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Securities registered pursuant to Section 12(g) of the Act: None

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Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ⌧☒ No ☐

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Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐ No ⌧☒

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Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ⌧☒ No ☐

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Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes ⌧☒ No ◻☐

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Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act. (Check one):

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If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

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Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

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If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

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Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

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Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes ☐ No ☒

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The aggregate market value of the registrant’s common stock held by non-affiliates as of June 30, 20212022 was $1.3 billion. Exclusion of shares held by any person should not be construed to indicate that such person possesses the power, direct or indirect, to direct or cause the actions of the management or policies of the registrant, or that such person is controlled by or under common control with the registrant.

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The number of shares of common stock outstanding at February 17, 202213, 2023 was 46,735,02647,207,189 shares.

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DOCUMENTS INCORPORATED BY REFERENCE

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Portions of the definitive Proxy Statement for our 20222023 Annual Meeting of Stockholders are incorporated by reference into Part III of this Report.

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CELLDEX THERAPEUTICS, INC.

ANNUAL REPORT ON FORM 10-K

FOR THE FISCAL YEAR ENDED DECEMBER 31, 20212022

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Safe Harbor Statement under the Private Securities Litigation Reform Act of 1995: This Annual Report on Form 10-K contains forward-looking statements made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995 under Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking statements include statements with respect to our beliefs, plans, objectives, goals, expectations, anticipations, assumptions, estimates, intentions and future performance, and involve known and unknown risks, uncertainties and other factors, which may be beyond our control and which may cause our actual results, performance or achievements to be materially different from future results, performance or achievements expressed or implied by such forward-looking statements. All statements other than statements of historical fact are statements that could be forward-looking statements. You can identify these forward-looking statements through our use of words such as “may,” “will,” “can,” “anticipate,” “assume,” “should,” “indicate,” “would,” “believe,” “contemplate,” “expect,” “seek,” “estimate,” “continue,” “plan,” “point to,” “project,” “predict,” “could,” “intend,” “target,” “potential” and other similar words and expressions of the future.

There are a number of important factors that could cause the actual results to differ materially from those expressed in any forward-looking statement made by us. These factors include, but are not limited to:

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All forward-looking statements are expressly qualified in their entirety by this cautionary notice. You are cautioned not to place undue reliance on any forward-looking statements, which speak only as of the date of this report or the date of the document incorporated by reference into this report. We have no obligation, and expressly disclaim any obligation, to update, revise or correct any of the forward-looking statements, whether as a result of new information, future events or otherwise. We have expressed our expectations, beliefs and projections in good faith, and we believe they have a reasonable basis. However, we cannot assure you that our expectations, beliefs or projections will result or be achieved or accomplished.

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PART I

Item 1. BUSINESS

Overview

Celldex Therapeutics, Inc., which we refer to as “Celldex,” “we,” “us,” “our” or the “Company,” is 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:of

We routinely work with external parties to collaboratively advance our drug candidates. In addition to Celldex-led studies, we also have an Investigator Initiated Research (IIR) program with multiple studies ongoing with our drug candidates.

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. Currently, all programs are fully owned by Celldex.

Our future success depends upon many factors, including our ability, and that of any licensees and collaborators that we may have, to successfully develop, obtain regulatory approval for and commercialize our drug candidates. We have had no commercial revenues from sales of our drug candidates, and we have had a history of operating losses. It is possible that we may not be able to successfully develop, obtain regulatory approval for, or commercialize, our drug candidates, and we are subject to a number of risks that you should be aware of before investing in us. These risks are described more fully in “Item 1A. Risk Factors.”

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In certain inflammatory diseases, such as chronic spontaneous urticaria (“CSU”)(CSU), also known as chronic idiopathic urticaria (“CIU”)(CIU), and chronic inducible urticaria (“CIndU”)(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 CDX-0159barzolvolimab in healthy subjects (n=(n = 32; 8 subjects per cohort, 6 CDX-0159;barzolvolimab; 2 placebo). Subjects received a single intravenous infusion of CDX-0159barzolvolimab 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. CDX-0159Barzolvolimab 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 CDX-0159barzolvolimab 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. The prevalence ofPhase 1 studies in CSU and CIndU is approximately 0.5-1% of the total population or upare 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 3 million patientsinitiate a Phase 2 study in eosinophilic esophagitis in the United States alone (Weller et al. 2010. Hautarzt. 61(8), Bartlett et al. 2018. DermNet. Org). 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. AboutCSU 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 or leukotriene receptor antagonists.antihistamines. Omalizumab, an IgE inhibitor, provides relief for roughly half of the remaining antihistamine/leukotrieneantihistamine refractory patients. Consequently, there is a need for additional therapies. CIndUs are forms of urticaria that have an attributable cause or trigger associated with them, typically resulting in hives or wheals. Celldex is exploring cold-induced, dermographism (scratch-induced) and cholinergic (exercise-induced) urticarias.

In October 2020, we announced that enrollment had opened and the first patient had been dosed in a Phase 1b multi-center study of CDX-0159barzolvolimab in CSU. This study is a randomized, double-blind, placebo- controlledplacebo-controlled clinical trial designed to assess the safety of multiple ascending doses of CDX-0159barzolvolimab 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. CDX-0159Barzolvolimab is administered intravenously (0.5, 1.5, 3 and 4.5 mg/kg at varying dosing schedules) as add on treatment to H1- antihistamines,H1-antihistamines, either alone or in combination with H2-antihistamines and/or leukotriene receptor agonists.

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

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(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 second 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 CDX-0159barzolvolimab in patients with cold urticaria (n=10)(ColdU) or symptomatic dermographism (n=10)(SD). In March and June 2021, respectively, we added a third cohort (single dose, 3 mg/kg) in patients with cholinergic urticaria (n=10) and a fourth cohort at a lower dose (single dose, 1.5 mg/kg) in cold urticaria.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. CDX-0159Barzolvolimab is administered intravenously on Day 1 as add on treatment to H1-antihistamines.

In July of 2021, we reported positive interimNovember 2022, data from the cold urticariaColdU and symptomatic dermographism cohorts. As of the data cut-off on June 11, 2021, 20 patients had receivedSD cohorts treated with a single intravenous infusion of CDX-0159barzolvolimab at 3 mg/kg including 11 patients with cold urticaria and 9 patients with symptomatic dermographism. Patients had high disease activity as assessed by provocation threshold testing. In patients with cold urticaria and symptomatic dermographism baseline critical temperature thresholds were 18.9°C/66°F (range: 5-27°C/41-80.6°F) and FricTest(R) thresholds were 3.8 (range: 3-4) of 4 pins.published in Allergy (Terhorst-Molawi et al Allergy. 2022 Nov 16. doi: 10.1111/all.15585). Safety results were reported for all 2021 patients; activity results were reported for the 1920 patients who received a full dose of CDX-0159. 14barzolvolimab. 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 19quality of life (QoL) and poorly controlled disease, respectively. Three patients completed the 12-week study observation period(1 with ColdU and five2 with SD) were ongoing (range of 2-8 weeks ) as of June 11, 2021.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.

In September of 2021, we reported additional positive data from the study on measurements of symptom control and quality of life. A single dose of CDX-0159 (3 mg/kg) resulted in a rapid and sustained improvement in urticaria control and greatly reduced disease impact on quality of life, as measured by the Urticaria Control Test (UCT) and Dermatology Life Quality Index (DLQI).

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CelldexIn 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.

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).

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Prurigo Nodularis (PN)

We have expanded clinical development of CDX-0159barzolvolimab into prurigo nodularis (“PN")(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 areis currently noonly one FDA approved therapiestherapy 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 CDX-0159barzolvolimab in up to 30 patients with PN.

Manufacturing activities Enrolling an intravenous, early stage study in the dermatology setting has been a challenge and the study has taken longer than expected to supportcomplete. 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 introductioncompletion of the CDX-0159 subcutaneous formulation into24 week follow up period post dosing for patients on study, we plan to present data from the clinical program have been completed and,study in September 2021, we initiated dosingthe second half of 2023. Potential future development in a randomized, double-blind, placebo-controlled, Phase 1 study designed to evaluate the safety of single ascending doses ofPN will utilize the subcutaneous formulation of CDX-0159 in healthy volunteers. In February 2022, we reported that subcutaneous administration of CDX-0159 was well tolerated and that multiple dose levels have been identified that possess promising pharmacokinetic and pharmacodynamic properties. Importantly, subcutaneous delivery of CDX-0159 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. Celldex anticipates the upcoming Phase 2 multi-dose studies in urticaria will evaluate 75mg and 150mg administered q4weeks and 300mg administered q8weeks. The planned doses support a 0.5 to 2 ml injection volume, allowing for a single injection as CDX-0159 advances towards potential commercialization. In 2022, we plan to initiate a transfer of our current CDX-0159 manufacturing process to a contract manufacturing organization to support late-stage trials and to prepare for potential commercialization.barzolvolimab.

In February 2022, we also reported interim data after completing the in-life dosing portion of our six month chronic toxicology study in non-human primates; a subset of the animals will continue to be followed beyond clearance of the CDX-0159 antibody to study completion. As expected and consistent with other KIT-targeting agents, impact on spermatogenesis was observed which is anticipated to be fully reversible upon clearance of the antibody. There were no other clinically adverse findings reported in the study. Celldex believes these data strongly support the Company’s planned Phase 2 studies in urticaria later this year and in future indications.Eosinophilic Esophagitis (EoE)

In February 2022, we announced that we will be expanding clinical development of CDX-0159barzolvolimab into eosinophilic esophagitis ("EoE")(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 are limited treatment options for EoE. Individuals often participate in an elimination diet to identify potential food allergens that may contribute to EoE, avoid difficult to swallow foods and undergo esophageal dilation. While notis only one FDA approved therapy for EoE, proton pump inhibitors and the swallowingrepresenting an area of topical corticosteroids are also used to address the disease.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 CDX-0159’sbarzolvolimab’s potential as a mast cell depleting agent, we believe EoE is an important indication for future study.

We continuestudy 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.

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 opportunitiescommercialization. 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 CDX-0159potential commercialization.

In February 2022, we reported interim data after completing the in-life dosing portion of our six-month chronic toxicology study in othernon-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.

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Bispecific Platform

Our next generation bispecific antibody platform is supporting the expansion of our pipeline with additional candidates for inflammatory diseases where mastand 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 playand myeloid cells, respectively. ILT4 is emerging as an important role, suchimmune 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 dermatologic, respiratory, allergic, gastrointestinalmonotherapy or in combination with other oncologic treatments and ophthalmic conditions.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 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. Potent CD40 agonist antibodies have shown encouraging results in early clinical studies; however, systemic toxicity associated with broad CD40 activation has limited their dosing concentrations to levels that may not be optimal for engaging CD40 expressing cells in the tumor microenvironment. CDX-1140 has unique properties relative to other CD40 agonist antibodies: potent agonist activity is independent of Fc receptor interaction, contributing to more consistent, controlled immune activation; CD40L binding is not blocked, leading to potential synergistic effects of agonist activity near activated T cells in lymph nodes and tumors; and the antibody does not promote cytokine production in whole blood assays. CDX-1140 has shown direct anti-tumor activity in preclinical models of lymphoma. Preclinical studies of CDX-1140

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Partnership agreements may terminate without benefit to us if the underlying products are not fully developed. If we fail to meet our obligations under these agreements, they could terminate, and we might need to enter into relationships with other collaborators and to spend additional time, money and other valuable resources in the process. We cannot predict whether our collaborators will continue their development efforts or, if they do, whether their efforts will achieve success. Many of our collaborators face the same kinds of risks and uncertainties in their businesses that we face. A delay or setback to a partner will, at a minimum, delay the commercialization of any affected drug candidates, and may ultimately prevent it. Moreover, any partner could breach its agreement with us or otherwise not use best efforts to promote our products. A partner may choose to pursue alternative technologies or products that compete with our technologies or drug candidates. In either case, if a partner failed to successfully develop one of our drug candidates, we would need to find another partner. Our ability to do so would depend upon our legal right to do so at the time and whether the product remained commercially viable.

Research Collaboration and License Agreements

We have entered into license agreements whereby we have received licenses or options to license technology, specified patents and/or patent applications. These license and collaboration agreements generally provide for royalty payments equal to specified percentages of product sales, annual license maintenance fees, continuing patent prosecution costs and potential future milestone payments to third parties upon the achievement of certain development, regulatory and/or commercial milestones. Summarized below are our significant research collaboration and license agreements for our current clinical drug candidates.

University of Southampton, UK (Southampton)

Under a license agreement with Southampton, we acquired the rights to develop human antibodies towards CD27, a potentially important target for immunotherapy of various cancers. We may be required to pay Southampton milestones of up to approximately $1.0 million upon obtaining first approval for commercial sale in a first indication and royalty payments in the low-single digits on any net product sales with respect to development and commercialization of CDX-527.

Amgen Inc. (Amgen)

Under a license agreement with Amgen, we acquired the exclusive rights to CDX-301 and CD40 ligand, or CD40L. CDX-301 and CD40L are immune modulating molecules that increase the numbers and activity of immune cells that control immune responses. We may be required to pay Amgen milestones of up to $0.9 million upon obtaining first approval for commercial sale in a first indication and royalty payments in the low-single digits on any net product sales with respect to development and commercialization of the technology licensed from Amgen, including CDX-301.

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biotechnology capabilities or made commercial arrangements with other biopharmaceutical companies to target the diseases on which we have focused both in the U.S. and outside of the U.S.

We also face competition in recruiting and retaining highly qualified scientific personnel and consultants and in the development and acquisition of technologies.

Our competitive position will depend upon our ability to attract and retain qualified personnel, obtain patent protection or otherwise develop proprietary products or processes and secure sufficient capital resources for the often lengthy period between technological conception and commercial sales. We will require substantial capital resources to complete development of some or all of our drug candidates, obtain the necessary regulatory approvals and successfully manufacture and market our drug candidates. In order to secure capital resources, we anticipate having to sell additional capital stock, which would dilute existing stockholders. We may also attempt to obtain funds through research grants and agreements with commercial collaborators. However, these types of funding are uncertain because they are at the discretion of the organizations and companies that control the funds. As a result, we may not receive any funds from grants or collaborations. Alternatively, we may borrow funds from commercial lenders, likely at high interest rates, which would increase the risk of any investment in us.

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Use of third-party manufacturers limits our control over and ability to monitor the manufacturing process. As a result, we may not be able to detect a variety of problems that may arise and may face additional costs in the process of interfacing with and monitoring the progress of our contract manufacturers. If third-party manufacturers fail to meet our manufacturing needs in an acceptable manner or fail to comply with regulatory requirements, we would face delays and additional costs while we develop internal manufacturing capabilities or find alternate third-party manufacturers. It may not be possible to have multiple third-party manufacturers ready to supply us with needed material at all or without incurring significant costs.

Commercial Organization

We have limited commercial experience in marketing, sales, distribution and product reimbursement. We have the capability to provide current and future market insights to our research and development organization regarding our potential drug candidates. In the future, we may choose to expand our commercial team and build a full-scale commercial organization which we believe could provide us the opportunity to retain marketing rights to our drug candidates and commercialize such products ourselves where we deem appropriate or pursue strategic partnerships to develop, sell, market and distribute our drug candidates where we deem appropriate.

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There can be no assurance that patent applications owned by or licensed to us will result in granted patents or that, if granted, the resultant patents will afford protection against competitors with similar technology. It is also possible that third parties may obtain patents or other proprietary rights that may be necessary or useful to us. In cases where third parties are first to invent a particular product or technology, it is possible that those parties will obtain patents that will be sufficiently broad to prevent us from using important technology or from further developing or commercializing important drug candidates and immunotherapeutic systems. If

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Proprietary Rights

We also rely on unpatented technology, trade secrets and confidential information, and no assurance can be given that others will not independently develop substantially equivalent information and techniques or otherwise gain access to our know-how and information, or that we can meaningfully protect our rights in such unpatented technology, trade secrets and information. We require each of our employees, consultants and advisors to execute a confidentiality agreement at the commencement of an employment or consulting relationship with us. The agreements generally provide that all inventions conceived by the individual in the course of employment or in providing services to us and all confidential information developed by, or made known to, the individual during the term of the relationship shall be the exclusive property of us and shall be kept confidential and not disclosed to third parties except in limited specified circumstances. There can be no assurance, however, that these agreements will provide meaningful protection for our information in the event of unauthorized use or disclosure of such confidential information.

Government Regulation

Our activities and products are significantly regulated by a number of governmental entities, including the U.S. Food and Drug Administration, or FDA, in the United States and by comparable authorities in other countries. These entities regulate, among other things, the manufacture, testing, safety, effectiveness, labeling, documentation, advertising and sale of our products. We must obtain regulatory approval from the FDA and comparable authorities in other countries, as applicable, for our drug candidates before we can commercialize such drugs in the U.S. and foreign jurisdictions. Product development within this regulatory framework takes a number of years and involves the expenditure of substantial resources. Many drug candidates that initially appear promising ultimately do not reach the market because they are found to be unsafe or ineffective when tested. Our inability to commercialize a product would impair our ability to earn future revenues.

FDA Approval Process

In the United States, the FDA regulates drugs and biological products under the Federal Food, Drug, and Cosmetic Act, or FDCA, the Public Health Service Act, or PHSA, and implementing regulations. The process of obtaining regulatory approvals and the subsequent compliance with appropriate federal, state, local and foreign statutes and regulations requires the expenditure of substantial time and financial resources. Failure to comply with the applicable United States requirements at any time during the product development process, approval process or after approval may subject an applicant to a variety of administrative or judicial sanctions, such as the FDA’s refusal to approve pending applications, withdrawal of an approval, imposition of a clinical hold, issuance of untitled or warning letters, product recalls, product seizures, total or partial suspension of production or distribution injunctions, fines, refusals of government contracts, restitution, disgorgement of profits, civil penalties and criminal prosecution.

The process required by the FDA before a drug or biological product may be marketed in the United States generally involves the following:

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We expect that all of our clinical drug candidates will be subject to review as biological products under BLA standards.

Data obtained at any stage of testing is susceptible to varying interpretations, which could delay, limit or prevent regulatory approval. Moreover, during the regulatory process, new or changed drug approval policies may cause unanticipated delays or rejection of our product. We may not obtain necessary regulatory approvals within a reasonable period of time, if at all, or avoid delays or other problems in testing our products. Moreover, even if we received regulatory approval for a product, the approval may require limitations on use, which could restrict the size of the potential market for the product.

Clinical Trials

The FDA provides that human clinical trials may begin 30 days after receipt and review of an IND application, unless the FDA requests additional information or changes to the study protocol within that period. An IND must be sponsored and filed for each of our proposed drug candidates. Authorization to conduct clinical trials in no way assures that the FDA will ultimately approve the product. Clinical trials are generally conducted in three sequential phases. In a Phase 1 trial, the product is given to a small number of patients to test for safety (adverse effects), determine a recommended Phase 2 dose(s) and evaluate any signals of efficacy. Phase 2 trials are conducted on a limited group of the target patient population; safety, optimal dosage and efficacy are studied. A Phase 3 trial is performed in a large patient population, generally over a wide geographic area to provide evidence for the safety and efficacy of the product. The FDA maintains and exercises oversight authority throughout the clinical trial process.

A product’s safety and effectiveness in one clinical trial is not necessarily indicative of its safety and effectiveness in another clinical trial. Moreover, we may not discover all potential problems with a product even after completing clinical trials on it. Some of our products and technologies have undergone only preclinical testing. As a result, we do not know whether they are safe or effective for humans. Also, regulatory authorities may decide, contrary to our findings, that a product is unsafe or not as effective in actual use as its clinical trial results indicated. This could prevent the product’s widespread use, require its withdrawal from the market or expose us to liability. The FDA or the sponsor may suspend or terminate a clinical trial at any time on various grounds, including a finding that the patients are being exposed to an unacceptable health risk. Similarly, an IRB can suspend or terminate approval of a clinical trial at its institution if the clinical trial is not being conducted in accordance with the IRB’s requirements or if the drug has been associated with unexpected serious harm to patients. Any such action could materially harm us. Clinical trials are critical to the success of our products but are subject to unforeseen and uncontrollable delay, including delay in enrollment of patients. Any delay in clinical trials could delay our commercialization of a product.

Marketing Approval

Assuming successful completion of the required clinical testing, the results of the preclinical and clinical studies, together with detailed information relating to the product’s pharmacology, chemistry, manufacture, controls and proposed labeling, among other things, are submitted to the FDA as part of an NDA or BLA requesting approval to market the product for one or more indications. FDA approval of the NDA or BLA is required before marketing of the product may begin in the United States. Under federal law, the submission of most NDAs and BLAs is additionally subject to a substantial application user fee and the sponsor of an approved NDA or BLA is also subject to annual prescription drug program fees.

The FDA conducts a preliminary review of all NDAs and BLAs within the first 60 days after receipt before accepting them for filing based on the agency’s threshold determination that they are sufficiently complete to permit substantive review. The FDA may request additional information rather than accept an NDA or BLA for filing. In this event, the application must be resubmitted with the additional information. The resubmitted application is also subject to review before the FDA accepts it for filing. Once the submission is accepted for filing, the FDA begins an in-depth substantive review. The FDA has agreed to specified performance goals in the review of NDAs and BLAs. Most such applications for non-priority products are reviewed within ten to twelve months after filing, and most applications for priority review products, that is, drugs and biologics that the FDA determines represent a significant improvement over existing therapy, are reviewed in six to eight months after filing. The review process may be extended by the FDA for three additional months to consider certain late-submitted information or clarification regarding information already provided in

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the submission. The FDA may also refer applications for novel drugs or biological products or products that present difficult questions of safety or efficacy to an advisory committee, typically a panel that includes clinicians and other experts, for review, evaluation and a recommendation as to whether the application should be approved. The FDA is not bound by the recommendations of an advisory committee, but it considers such recommendations carefully when making decisions.

Before approving an NDA or BLA, the FDA typically will inspect the facility or facilities where the product is manufactured. The FDA will not approve an application unless it determines that the manufacturing processes and facilities are in compliance with cGMP requirements and adequate to assure consistent production of the product within required specifications. In addition, before approving an NDA or BLA, the FDA will typically inspect one or more clinical sites to assure compliance with GCP and integrity of the clinical data submitted.

The testing and approval processes require substantial time, effort and financial resources, and each may take many years to complete. Data obtained from clinical activities are not always conclusive and may be susceptible to varying interpretations that could delay, limit or prevent regulatory approval. The FDA may not grant approval on a timely basis, or at all. We may encounter difficulties or unanticipated costs in our efforts to develop our drug candidates and secure necessary governmental approvals, which could delay or preclude us from marketing our products.

After the FDA’s evaluation of the NDA or BLA and inspection of the manufacturing facilities, the FDA may issue an approval letter or a complete response letter. An approval letter authorizes commercial marketing of the drug or biological product with specific prescribing information for specific indications. A complete response letter generally outlines the deficiencies in the submission and may require substantial additional testing or information in order for the FDA to reconsider the application. If and when those deficiencies have been addressed to the FDA’s satisfaction in a resubmission of the NDA or BLA, the FDA will resume review and may subsequently issue an approval letter. The FDA has committed to reviewing such resubmissions in two or six months depending on the type of information included. Even with submission of this additional information, the FDA ultimately may decide that the application does not satisfy the regulatory criteria for approval.

Even if the FDA approves a product, it may limit the approved indications for use for the product, require that contraindications, warnings or precautions be included in the product labeling, require that post- approval studies, including Phase 4 clinical trials, be conducted to further assess a drug’s safety after approval, require testing and surveillance programs to monitor the product after commercialization, or impose other conditions, including distribution restrictions or other risk management mechanisms, which can materially affect the potential market and profitability of the product. The FDA may prevent or limit further marketing of a product based on the results of post-market studies or surveillance programs. After approval, many types of changes to the approved product, such as changes in indications, manufacturing changes and labeling, are subject to further testing requirements and FDA review and approval.

Special Regulatory Procedures

Fast track designation — The FDA is required to facilitate the development and expedite the review of drugs and biologics that are intended for the treatment of a serious or life-threatening disease or condition and that demonstrate the potential to address unmet medical needs. Under the fast track program, the sponsor of a new drug or biologic candidate may request the FDA to designate the product for a specific indication as a fast track product, concurrent with or after the filing of the IND for the drug candidate. A drug that receives fast track designation is eligible for some or all of the following: (i) more frequent meetings with the FDA to discuss the drug’s development plan and ensure collection of appropriate data needed to support drug approval; (ii) more frequent written communication from the FDA about such things as the design of the proposed clinical trials and use of biomarkers; (iii) eligibility for accelerated approval and priority review, if relevant criteria are met; and (iv) Rolling“Rolling Review,” which means that a drug company can submit completed sections of its BLA or NDA for review by the FDA, rather than waiting until every section of the NDA or BLA is completed before the entire application can be reviewed. This rolling review is available if the applicant provides and the FDA approves a schedule for the submission of the remaining information and the applicant pays applicable user fees. However, the FDA’s time period goal for reviewing a fast track application does not begin until the last section of the NDA or BLA is submitted. In addition, the fast track designation may be withdrawn by the FDA if it believes that the designation is no longer supported by data emerging in the clinical trial process.

Priority review — Under FDA policies, a drug candidate may be eligible for priority review. The priority review program provides for expedited review or an NDA or BLA, typically within a six to eight month time frame from the time a complete application is accepted for filing. Products regulated by the FDA’s Center for Drug Evaluation and Research, or CDER, are eligible

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for priority review if they provide a significant improvement compared to marketed products in the treatment, diagnosis or prevention of a disease. Products regulated by the FDA’s Center for Biologics Evaluation and Research, or CBER, are eligible for priority review if they provide a significant improvement in the safety or effectiveness of the treatment, diagnosis or prevention of a serious or life-threatening disease. A fast track designated drug candidate could be eligible for priority review if supported by clinical data at the time of the BLA or NDA submission.

Accelerated approval — Under the law and the FDA’s accelerated approval regulations, the FDA may approve a drug or biologic for a serious or life-threatening illness that provides meaningful therapeutic benefit to patients over existing treatments based on a surrogate endpoint that is reasonably likely to predict clinical benefit. Surrogate endpoints can often be measured more easily or more rapidly than clinical endpoints. A drug candidate approved on this basis is subject to rigorous post-marketing compliance requirements, including the completion of Phase 4 or post-approval clinical trials to confirm the effect on the clinical endpoint. Failure to conduct required post-approval studies, or confirm a clinical benefit during post-marketing studies, would allow the FDA to withdraw the drug from the market on an expedited basis. All promotional materials for drug candidates approved under accelerated regulations are subject to prior review by the FDA.

Breakthrough therapy designation — The FDA is also required to expedite the development and review of the application for approval of drugs that are intended to treat a serious or life-threatening disease or condition where preliminary clinical evidence indicates that the drug candidate may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints. Under the breakthrough therapy program, the sponsor of a new drug candidate may request that the FDA designate the drug candidate for a specific indication as a breakthrough therapy concurrent with, or after, the filing of the IND for the drug candidate.

Orphan drug designation — Under the Orphan Drug Act, the FDA may grant orphan drug designation to a drug or biologic intended to treat a rare disease or condition, which is generally defined as a disease or condition that affects fewer than 200,000 individuals in the United States. Orphan drug designation does not convey any advantage in, or shorten the duration of, the regulatory review and approval process. The first NDA or BLA applicant to receive FDA approval for a particular active ingredient to treat a particular disease with FDA orphan drug designation is entitled to a seven-year exclusive marketing period in the United States for that product, for that indication. During the seven-year exclusivity period, the FDA may not approve any other applications to market the same drug or biologic for the same orphan indication, except in limited circumstances. Among the other benefits of orphan drug designation are tax credits for certain research and a waiver of the NDA or BLA application user fee.

Pediatric Information

Under the Pediatric Research Equity Act of 2003, an NDA, BLA or supplement to an NDA or BLA must contain data that are adequate to assess the safety and effectiveness of the drug or biological product for the claimed indications in all relevant pediatric subpopulations, and to support dosing and administration for each pediatric subpopulation for which the product is safe and effective. The FDA may, on its own initiative or at the request of the applicant, grant deferrals for submission of some or all pediatric data until after approval of the product for use in adults, or full or partial waivers from the pediatric data requirements. Under the Food and Drug Administration Safety and Innovation Act, or FDASIA, the FDA has additional authority to take action against manufacturers not adhering to pediatric study requirements. Unless otherwise required by regulation, the pediatric data requirements do not apply to products with orphan drug designation.

Post Approval

Any drug or biological products manufactured or distributed by us pursuant to FDA approvals are subject to pervasive and continuing regulation by the FDA, including, among other things, requirements relating to recordkeeping, periodic reporting, product sampling and distribution, advertising and promotion and reporting of adverse experiences with the product. After approval, most changes to the approved product, such as adding new indications or other labeling claims are subject to prior FDA review and approval.

The FDA may impose a number of post-approval requirements as a condition of approval of an NDA or BLA. For example, the FDA may require post-marketing testing, including Phase 4 clinical trials, and surveillance to further assess and monitor the product’s safety and effectiveness after commercialization. Regulatory approval of oncology products often requires that patients in clinical trials be followed for long periods to determine the overall survival benefit of the drug or biologic.

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In addition, drug and biologic manufacturers and other entities involved in the manufacture and distribution of approved drugs and biological products are required to register their establishments with the FDA and state agencies and are subject to periodic unannounced inspections by the FDA and these state agencies for compliance with cGMP requirements. The FDA was also granted new inspection authorities under FDASIA. Changes to the manufacturing process are strictly regulated and often require prior FDA approval before being implemented. FDA regulations also require investigation and correction of any deviations from cGMP and impose reporting and documentation requirements upon us and any third-party manufacturers that we may decide to use. Accordingly, manufacturers must continue to expend time, money and effort in the areas of production and quality control to maintain cGMP compliance.

Once an approval is granted, the FDA may withdraw the approval if compliance with regulatory requirements and standards is not maintained or if problems occur after the product reaches the market. Later discovery of previously unknown problems with a product, including adverse events of unanticipated severity or frequency, or with manufacturing processes, or failure to comply with regulatory requirements, may result in revisions to the approved labeling to add new safety information, imposition of post-market studies or clinical trials to assess new safety risks or imposition of distribution or other restrictions under a Risk Evaluation and Mitigation Strategy program. Other potential consequences include, among other things:

The FDA strictly regulates marketing, labeling, advertising and promotion of products that are placed on the market. Drugs and biologics may be promoted only for the approved indications and in accordance with the provisions of the approved label. The FDA, the Office of the Inspector General of Health and Human Services and other agencies actively enforce the laws and regulations prohibiting the promotion of off label uses, and a company that is found to have improperly promoted off label uses may be subject to significant liability.

Biosimilars Law

The Biologics Price Competition and Innovation Act of 2009, or BPCIA, amended the PHSA to provide for an abbreviated approval pathway for biological products that demonstrate biosimilarity to a previously-approved biological product. The BPCIA establishes criteria for determining that a product is biosimilar to an already-licensed biologic, or reference product, and establishes a process by which an abbreviated BLA for a biosimilar product is submitted, reviewed and approved. The BPCIA provides periods of exclusivity that protect a reference product from biosimilars competition. Under the BPCIA, the FDA may not accept a biosimilar application for review until four years after the date of first licensure of the reference product, and the biosimilar may not be licensed until 12 years after the reference product’s approval. Additionally, the BPCIA establishes procedures by which the biosimilar applicant may provide information about its application and product to the reference product sponsor, and by which information about potentially relevant patents is shared and litigation over patents may proceed in advance of approval. The BPCIA also provides a period of exclusivity for the first biosimilar to be determined by the FDA to be interchangeable with the reference product. The BPCIA applies to our drug candidates and could be applied to allow approval of biosimilars to our products.

21st Century Cures Act

On December 13, 2016, Congress passed the 21st Century Cures Act, or the Cures Act. The Cures Act is designed to modernize and personalize health care, spur innovation and research, and streamline the discovery and development of new therapies through increased federal funding of particular programs. It authorizes increased funding for the FDA to spend on innovation projects, including for certain oncology- directed research. The new law also amends the Public Health Service Act to reauthorize and expand funding for the National Institutes of Health.

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The Cures Act also authorizes funding for the “Cancer Moonshot” initiative. The Cancer Moonshot initiative’s strategic goals encourage inter-agency cooperation and fund research and innovation to catalyze new scientific breakthroughs, bring new therapies to patients and strengthen prevention and diagnosis. This initiative aims to stimulate drug development through the creation of a public-private partnership with 20 to 30 pharmaceutical and biotechnology companies to expedite cancer researchers’ access to investigational agents and approved drugs. This partnership is designed to permit researchers to obtain drugs and other technologies from a preapproved “formulary” list without having to negotiate with each company for individual research projects. We will continue to monitor these developments to assess their potential impacts on our business.

Companion Diagnostic Review and Approval

Our drug candidates may rely on the use of a companion diagnostic. Companion diagnostics are subject to regulation by the FDA and comparable foreign regulatory authorities as medical devices and require separate clearance or approval prior to their commercialization. Based on recent FDA guidance documents and the FDA’s past treatment of companion diagnostics, we believe that the FDA will likely require one or more of our in vitro companion diagnostics to obtain Premarket Approval Application, or PMA, in conjunction with approval of the related drug candidate. The receipt and timing of PMA approval may have a significant effect on the receipt and timing of commercial approval for such drug candidates.Currently we rely on third-party collaborators to develop companion diagnostics for our drug candidates.

The PMA process is similar to the NDA and BLA processes and is costly, lengthy and uncertain. PMA applications must be supported by valid scientific evidence, which typically requires extensive data, including technical, preclinical, clinical and manufacturing data, to demonstrate to the FDA’s satisfaction the safety and effectiveness of the device. For diagnostic tests, a PMA application typically includes data regarding analytical and clinical validation studies. As part of its review of the PMA, the FDA will conduct a pre-approval inspection of the manufacturing facility or facilities to ensure compliance with the Quality System Regulation, or QSR, which requires manufacturers to follow design, testing, control, documentation and other quality assurance procedures. If the FDA evaluations of both the PMA application and the manufacturing facilities are favorable, the FDA will either issue an approval letter or an approvable letter, which usually contains a number of conditions that must be met in order to secure the final approval of the PMA. If the FDA’s evaluation of the PMA or manufacturing facilities is not favorable, the FDA will deny approval of the PMA or issue a not approvable letter. A not approvable letter will outline the deficiencies in the application and, where practical, will identify what is necessary to make the PMA approvable. The FDA may also determine that additional clinical trials are necessary, in which case the PMA approval may be delayed while the trials are conducted and then the data submitted in an amendment to the PMA.

Furthermore, even after PMA approval is obtained, numerous regulatory requirements apply to the manufacturer of the companion diagnostic. The FDA enforces these requirements by inspection and market surveillance. These requirements include: the QSR, labeling regulations, the FDA’s general prohibition against promoting products for unapproved or “off label” uses, the medical device reporting regulation, and the reports of corrections and removals regulation. If the FDA finds a violation, it can institute a wide variety of enforcement actions, ranging from a public warning letter to more severe sanctions such as: fines, injunctions and civil penalties; recall or seizure of products; operating restrictions, partial suspension or total shutdown of production; refusing requests for PMA of new products; and withdrawing PMAs already granted.

Federal and State Fraud and Abuse, Data Privacy and Security and Transparency Laws

In addition to FDA restrictions on marketing and promotion of pharmaceutical products, several other types of federal and state laws have been applied to restrict certain marketing business practices in the biopharmaceutical and medical device industries in recent years. These laws include, without limitation, state and federal anti-kickback statutes and false claims statutes and false claims laws, data privacy and security laws, as well as transparency laws regarding payments or other items of value provided to health care providers. Applicable state law may be broader in scope than federal law and may apply regardless of payor, in addition to items and services reimbursed under Medicaid and other state programs. If our operations are found to be in violation of any of the health regulatory laws described above or any other laws that apply to us, we may be subject to penalties, including potentially significant criminal and civil and/or administrative penalties, damages, fines, disgorgement, imprisonment, exclusion from participation in government health care programs, contractual damages, reputational harm, administrative burdens, diminished profits and future earnings, and the curtailment or restructuring of our operations, any of which could adversely affect our ability to operate our business and our results of operations. To the extent that any of our products are sold in a foreign country, we may be subject to similar foreign laws, which may include, for instance, applicable post-marketing requirements, including safety surveillance, anti-fraud and abuse laws and implementation of corporate compliance programs and reporting of payments or transfers of value to health care professionals.

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In addition, the United States Foreign Corrupt Practices Act, or FCPA, prohibits corporations and individuals from engaging in certain activities to obtain or retain business or to influence a person working in an official capacity. It is illegal to pay, offer to pay or authorize the payment of anything of value to any official of another country, government staff member, political party or political candidate in an attempt to obtain or retain business or to otherwise influence a person working in that capacity. In many countries, the health care professionals we may interact with may meet the FCPA’s definition of a foreign government official.

Foreign Regulation

In order to market any therapeutic or diagnostic product outside of the United States, we need to comply with numerous and varying regulatory requirements of other countries regarding safety and efficacy and governing, among other things, clinical trials, marketing authorization, commercial sales and distribution of our products. Whether or not we obtain FDA approval for a product, we need to obtain the necessary approvals by the comparable regulatory authorities of foreign countries before we can commence clinical trials or marketing of the product in those countries. The approval process varies from country to country and can involve additional product testing and additional administrative review periods. The time required to obtain approval in other countries might differ from and be longer than that required to obtain FDA approval. Regulatory approval in one country does not ensure regulatory approval in another, but a failure or delay in obtaining regulatory approval in one country may negatively impact the regulatory process in others.

Under the EU regulatory system, we will submit most of our marketing authorization applications under the centralized procedure. The centralized procedure is compulsory for medicines produced by biotechnology, or are for the treatment of cancer, or officially designated as ‘orphan medicines.’ The centralized procedure provides for the grant of a single marketing authorization that is valid for all EU member states. As in the United States, we may apply for designation of a drug candidate as an orphan drug for the treatment of a specific indication in the EU before the application for marketing authorization is made. The European Medicines Agency (“EMA”) grants orphan medicinal product designation to promote the development of products that may offer therapeutic benefits for life-threatening or chronically debilitating conditions affecting not more than five in 10,000 people in the EU. Orphan drugs in Europe enjoy economic and marketing benefits, including a 10-year market exclusivity period for the approved indication, but not for the same product, unless another applicant can show that its product is safer, more effective or otherwise clinically superior to the orphan-designated product.

Other Regulatory Processes

From time to time, legislation is drafted, introduced and passed in Congress that could significantly change the statutory provisions governing the testing, approval, manufacturing and marketing of products regulated by the FDA.

In addition to new legislation, FDA regulations and policies are often revised or interpreted by the agency in ways that may significantly affect our business and our products. It is impossible to predict whether further legislative changes will be enacted or whether FDA regulations, guidance, policies or interpretations will change or what the effect of such changes, if any, may be.

Third-Party Payor Coverage and Reimbursement

Significant uncertainty exists as to the coverage and reimbursement status of any drug products for which we obtain regulatory approval. Sales of any of our drug candidates, if approved, will depend, in part, on the extent to which the costs of the drugs will be covered by third-party payors, including government health programs such as Medicare and Medicaid, as well as commercial health insurers, such as managed care organizations. The process for determining reimbursement rates is separate from the payor coverage decision. Therefore, despite obtaining coverage, reimbursement rates may be lower than expected, which can result in larger out-of-pocket payments for the patient.

In order to secure coverage and reimbursement for any drug that might be approved for sale, we need to conduct analyses and pharmaco-economic studies in order to demonstrate the incremental medical benefit over and above the generally-accepted standard of care and cost-effectiveness of the drug. Our drug candidates may not be considered medically necessary, provide insufficient incremental medical benefit, or may not be deemed cost-effective. A payor’s decision to provide coverage for a drug product does not imply that an adequate reimbursement rate will be approved.

The containment of health care costs has become a priority of federal, state and foreign governments, and the prices of drugs have been a focus in this effort. Third-partyGiven that the Inflation Reduction Act is now in place, potential implications for the biopharma industry are being assessed. In the meantime, third-party payors are increasingly challenging the prices charged for medical products and services

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and examining the medical necessity and cost-effectiveness of medical products and services, in addition to their safety and efficacy. If

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respectively. We anticipate that a significant portion of our operating expenses will continue to be related to research and development in 20222023 as we continue to advance our drug candidates through clinical development.

Corporate and Available Information

We are incorporated in Delaware. Our website is located at http://www.celldex.com. On our website, investors can obtain, free of charge, a copy of our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, our Code of Conduct and Business Ethics, including disclosure related to any amendments or waivers thereto, other reports and any amendments thereto filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act of 1934, as amended, as soon as reasonably practicable after we file such material electronically with, or furnish it to, the Securities and Exchange Commission, or the SEC. None of the information posted on our website is incorporated by reference into this Annual Report. The SEC also maintains a website at http://www.sec.gov that contains reports, proxy and information statements and other information regarding us and other companies that file materials with the SEC electronically.

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Risks Related to Business Operations

Risks Related to Intellectual Property

Regulatory Risks

Risks Related to Our Capital Stock

General Risk Factors

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Risks Related to Our Financial Condition and Capital Requirements

We currently have no product revenue and will need to raise capital to operate our business.

To date, we have generated no product revenue and cannot predict when and if we will generate product revenue. We had an accumulated deficit of $1.1$1.3 billion as of December 31, 2021.2022. Until, and unless, we complete clinical trials and other development activity, and receive approval from the FDA and other regulatory authorities, for our drug candidates, we cannot sell our drugs and will not have product revenue. We expect to spend substantial funds to continue the research, development and testing of our products that are in the preclinical and clinical testing stages of development and to prepare to commercialize products in anticipation of FDA approval. Therefore, for the foreseeable future, we will have to fund all of our operations and development expenditures from cash on hand, equity or debt financings, licensing fees and grants. Additional financing will be required to meet our liquidity needs. If we do not succeed in raising additional funds on acceptable terms, we might not be able to complete planned preclinical and clinical trials or obtain approval of any drug candidates from the FDA and other regulatory authorities. In addition, we could be forced to discontinue product development, reduce or forego sales and marketing efforts, forego attractive business opportunities or curtail operations. Any additional sources of financing could involve the issuance of our equity securities, which would have a dilutive effect on our stockholders. No assurance can be given that additional financing will be available to us when needed on acceptable terms, or at all.

We cannot be certain that we will achieve or sustain profitability in the future. Failure to achieve profitability could diminish our ability to sustain operations, pay dividends on our common stock, obtain additional required funds and make required payments on our present or future indebtedness.

We expect to incur future losses and we may never become profitable.

We have incurred operating losses of $115.2 million, $71.2 million and $63.4 million during 2022, 2021 and $55.0 million during 2021, 2020, and 2019, respectively, and expect to incur an operating loss in 20222023 and beyond. We believe that operating losses will continue in 20222023 and beyond because we are planning to incur significant costs associated with the development of our drug candidates. During the years ended December 31, 2022, 2021 2020 and 2019,2020, we incurred $23.8 million, $8.0 million $4.9 million and $4.3$4.9 million in clinical trial expense and $4.5 million, $1.7 million $1.2 million and $0.6$1.2 million in contract manufacturing expense. Our net losses have had and will continue to have an adverse effect on, among other things, our stockholders’ equity, total assets and working capital. We expect that losses will fluctuate from quarter to quarter and year to year, and that such fluctuations may be substantial. We cannot predict when we will become profitable, if at all.

We will need additional capital to fund our operations, including the development, manufacture and potential commercialization of our drug candidates. If we do not have or cannot raise additional capital when needed, we may be unable to develop and ultimately commercialize our drug candidates successfully.

We expect to incur significant costs as we develop our drug candidates. The continuing development and commercialization of our drug candidates requires additional capital beyond our current resources. As of December 31, 2021,2022, we had cash, cash equivalents and marketable securities of $408.3$305.0 million. During the next twelve months and beyond, we will take further steps to raise additional capital to fund our long-term liquidity needs. Our capital raising activities may include, but may not be limited to, one or more of the following:

While we may seek capital through a number of means, 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 financing 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 drug candidates under development. If we are unable to raise the funds necessary to meet our liquidity needs, we may

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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 significant discount or on other unfavorable terms, if at all, or sell all or part of our business.

Our stockholders may be subject to substantial dilution if we elect to pay future milestone consideration to the former Kolltan stockholders in shares of common stock. If we elect to pay future milestone consideration in cash, we would likely need to raise additional capital.

TheIn connection with the agreement pursuant to which we acquired Kolltan in 2016 (the “Merger Agreement”) as modified by the definitive settlement agreement (the “Settlement Agreement”) we entered on July 15, 2022 related to litigation arising from the Kolltan merger, agreement between usin the event that certain specified milestones related to the successful completion of a Phase 2 clinical trial of CDX-0159 or regulatory approval by the United States Food and Kolltan (“Merger Agreement”) provides thatDrug Administration or European Medicines Agency of certain drug candidates are achieved, we will be required to pay Kolltan’sto the former stockholders contingent consideration in the form of development, regulatory approval and sales-based milestones (“Kolltan Milestones”) of up to $172.5 million. Certain Kolltan Milestones related to the METRIC clinical study, TAM partnership closing within two years of the acquisition, CDX-3379 and CDX-0158 have been abandoned. We previously sent abandonment notices to the representative of Kolltan’s former stockholders, Shareholder Representative Services LLC (“SRS”), with respect to each of the abandoned Kolltan Milestones, and the representative subsequently objected to the abandonment notices for CDX-3379 and CDX-0158. We disagree with their objection and believe their objection to be without merit.

We have filed a Verified Complaint in the Court of Chancery of the State of Delaware against SRS seeking declaratory relief with respect to the rights and obligations of the parties relating to certain contingent milestone payments, underwhich milestone payments may be made, at our sole election, in cash, in shares of our common stock or a combination of both, subject to provisions of the Merger Agreement. In SRS’ responsive Answer and Verified Counterclaim, SRS made claims of breach of contract with respectPursuant to the MergerSettlement Agreement, breach of implied covenant of good faith and fair dealing, declaratory relief, and unjust enrichment regarding abandonment of the CDX-0158 milestones. At this time, we are unable to reasonably assess the ultimate outcome of our litigation with the representative of Kolltan’s former stockholders over its objection to our abandonment of certain Kolltan Milestones or determine an estimate of potential losses, if any. Further, there are disagreements between that representative and us with respect to our abandonment notice related to the discontinued CDX-3379 program. The case remains ongoing and we are currently unable to predict or estimate the outcome of this matter. The case is currently scheduled for trial in June 2022. The parties entered into non-binding mediation in May 2021 following SRS’s approach to Celldex about its interest in settlement or mediation discussions, but those discussions did not result in a resolution of the dispute. Asas of December 31, 2021, we believe2022 we may be requiredobligated to make milestone payments in an amount of up to $107.5 million.$65,000,000. If we elect to issue shares of our common stock to make these milestone payments, you will experience further dilution.

Milestone payments under the Merger Agreement may be made, at our sole election, in cash, in shares of our common stock or a combination of both, although we are required to maintain a certain percentage of the overall consideration paid in Celldex common stock to satisfy certain tax requirements under the Merger Agreement. We may require additional capital to fund any milestone payments in cash, depending on the facts and circumstances at the time such payments become due. The number of shares of our common stock issuable in connection with a milestone payment, if any, will be determined based on the average closing price per share of our common stock for the five trading day period ending three calendar days prior to the achievement of such milestone. If we elect to pay the Kolltan Milestones in shares of our common stock, our stockholders would experience substantial dilution.

U.S. federal income tax reform could adversely affect us.

On March 27, 2020, in response to COVID-19, U.S. Congress enacted the Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”) was enacted.. The CARES Act modified the Tax Cuts and Jobs Act (“TCJA”) by, among other things, eliminating the limitation on the deduction of net operating losses to 80% of current year taxable income for tax years beginning before January 1, 2021, and increasing the amount of interest expense that may be deducted from 30% to 50% of adjusted taxable income for tax years beginning in 2019 or 2020. We continue to examine the impact of this tax reform legislation, as well as any additional regulatory guidance that may be issued, may have on our business. For example, the recent change of administration could result in additional tax legislative activity that could have a material adverse effect on the Company.

Risks Related to Development and Regulatory Approval of Drug Candidates

Our long termlong-term success depends heavily on our ability to fund and complete the research and development activities and obtain regulatory approval for our program assets.

Only a small minority of all research and development programs ultimately result in commercially successful drugs. Clinical failure can occur at any stage of clinical development. Clinical and preclinical trials may produce negative or inconclusive results, and we may

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Our drug candidates are subject to extensive regulatory scrutiny.

All of our drug candidates are at various stages of development, and our activities and drug candidates are significantly regulated by a number of governmental entities, including the FDA in the United States and by comparable authorities in other countries. These entities regulate, among other things, the manufacture, testing, safety, effectiveness, labeling, documentation, advertising and sale of drugs and drug candidates. We or our partners must obtain regulatory approval for a drug candidate in all of these areas before we can commercialize any of our drug candidates. Product development within this regulatory framework takes a number of years and involves the expenditure of substantial resources. This process typically requires extensive preclinical and clinical testing, which may take longer or cost more than we anticipate, and may prove unsuccessful due to numerous factors. Many drug candidates that initially appear promising ultimately do not reach the market because they are found to be unsafe or ineffective when tested. Companies in the pharmaceutical, biotechnology and immunotherapeutic drug industries have suffered significant setbacks in advanced clinical trials, even after obtaining promising results in earlier trials. Our inability to commercialize a drug candidate would impair our ability to earn future revenues.

If our drug candidates do not pass required tests for safety and effectiveness, we will not be able to obtain regulatory approval and derive commercial revenue from them.

In order to succeed, we will need to obtain regulatory approval for our drug candidates. The FDA has not approved any of our drug candidates for sale to date. Our drug candidates are in various stages of preclinical and clinical testing. Preclinical tests are performed at an early stage of a product’s development and provide information about a drug candidate’s safety and effectiveness before initiating human clinical trials. Preclinical tests can last years. If a product passes its preclinical tests satisfactorily and we determine that further development is warranted, we would file an IND application for the product with the FDA, and, if the FDA gives its approval, we would begin Phase 1 clinical tests. Phase 1 testing generally lasts between 6 and 24 months. If Phase 1 test results are satisfactory and the FDA gives its approval, we can begin Phase 2 clinical tests. Phase 2 testing generally lasts between 6 and 36 months. If Phase 2 test results are satisfactory and the FDA gives its approval, we can begin Phase 3 pivotal studies. Phase 3 studies generally last between 12 and 48 months. Once clinical testing is completed and a BLA or NDA is filed with the FDA, it may take more than a year to receive FDA approval.

In all cases we must show that a drug candidate is both safe and effective before the FDA, or drug approval agencies of other countries where we intend to sell the product, will approve it for sale. Our research and testing programs must comply with drug approval requirements both in the United States and in other countries, since we are developing our drug candidates with the intention to, or could later decide to, commercialize them both in the U.S. and abroad. A product may fail for safety or effectiveness at any stage of the testing process. A major risk we face is the possibility that none of our products under development will come through the testing process to final approval for sale, with the result that we cannot derive any commercial revenue from them after investing significant amounts of capital in multiple stages of preclinical and clinical testing.

Success in early clinical trials does not ensure that later clinical trials will be successful, and we cannot assure you that any of the clinical trials that we may conduct will demonstrate consistent or adequate efficacy and safety to obtain regulatory approval.

The results of preclinical studies and early clinical trials may not be predictive of the results of later- stage clinical trials, and interim results of a clinical trial do not necessarily predict final results. Preclinical and clinical data are susceptible to various interpretations and analyses, and many companies that have believed their drug candidates performed satisfactorily in preclinical studies and early-stage clinical trials have nonetheless failed to replicate such results in later-stage clinical trials and subsequently

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have experienced difficulty enrolling patients, and we may experience more difficulty as the scale of our clinical testing program increases. The factors that affect our ability to enroll patients are largely uncontrollable and include principally the following:

If we cannot enroll patients as needed, our costs may increase, or we may be forced to delay or terminate testing for a product.

We may have delays in commencing, enrolling and completing our clinical trials, and we may not complete them at all.

We have not completed the clinical trials necessary to obtain FDA approval to market any of our drug candidates in development. Clinical trials for our products in development may be delayed or terminated as a result of many factors, including the following:

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If serious adverse or unacceptable side effects are identified during the development of our drug candidates, such events could prevent us from obtaining regulatory approval or achieving market acceptance of our drug candidates, and we may need to abandon or limit our development of some of our drug candidates.

If our drug candidates are associated with serious adverse events or undesirable side effects in clinical trials or have characteristics that are unexpected, such events could prevent us from obtaining regulatory approval or achieving market acceptance of our drug candidates, and we may need to abandon their development or limit development to more narrow uses or subpopulations in which the serious adverse events, undesirable side effects or other characteristics are less prevalent, less severe or more acceptable from a risk-benefit perspective. In pharmaceutical development, many drugs that initially show promise in early-stage testing are later found to cause side effects that prevent further development of the drug. Currently marketed therapies for the treatment of cancer and inflammatory diseases are generally limited to some extent by their toxicity. In addition, some of our drug candidates would be chronic therapies or be used in pediatric populations, for which safety concerns may be particularly important. Use of our drug candidates as monotherapies may also result in adverse events consistent in nature with those associated with other marketed therapies. In addition, when used in combination with other marketed therapies, our drug candidates may exacerbate adverse events associated with the marketed therapy.

Our drug candidates, including barzolvolimab, are monoclonal antibodies, which are biologics. Side effects from biologics may include hypersensitivity; severe reactions such as anaphylaxis or cytokine release syndrome; immune-mediated adverse reactions that may occur in any organ system or tissue, such as pneumonitis, colitis, hepatitis, endocrinopathies, nephritis, and dermatologic reactions; as well as infusion-related reactions, cellulitis, sepsis, pneumonia, urinary tract infection, fatigue, rash, and diarrhea.

Most biologics, including some of our drug candidates, are injected, either subcutaneously or intravenously. There are risks inherent in subcutaneous injections, such as injection-site reactions (including redness, itching, swelling, pain, and tenderness) and other side effects. In addition, there are risks inherent in intravenous administration such as infusion-related reactions (including nausea, pyrexia, rash, and dyspnea). These and other complications or side effects could harm further development and/or commercialization of our antibody-based products and product candidates utilizing this method of administration.

In addition to the safety, efficacy, manufacturing, and regulatory hurdles faced by our product candidates, the administration of biologics frequently causes an immune response, sometimes resulting in the creation of antibodies against the drug candidate which can impact the safety and/or efficacy associated with the treatment.

We may expend our resources to pursue a particular drug candidate or indication and forgo the opportunity to capitalize on drug candidates or indications that may ultimately be more profitable or for which there is a greater likelihood of success.

Because we have limited financial and managerial resources, we intend to focus on developing drug candidates for specific indications that we identify as most likely to succeed, in terms of both their potential for regulatory approval and commercialization. As a result, we may forego or delay pursuit of opportunities with other drug candidates or for other indications that may prove to have greater commercial potential.

Our resource allocation decisions may cause us to fail to capitalize on viable commercial drugs or profitable market opportunities. Our spending on current and future research and development programs and drug candidates for specific indications may not yield any commercially viable drug candidates. If we do not accurately evaluate the commercial potential or target market for a particular drug candidate, we may relinquish valuable rights to that drug candidate through collaboration, licensing or other royalty arrangements in cases in which it would have been more advantageous for us to retain sole development and commercialization rights to the drug candidate.

We may be unable to manage multiple late-stage clinical trials for a variety of drug candidates simultaneously.

As our current clinical trials progress, we may need to manage multiple late-stage clinical trials simultaneously in order to continue developing all of our current products. The management of late-stage clinical trials is more complex and time consuming than early-stage trials. Typically, early-stage trials involve several hundred patients in no more than 10 to 30 clinical sites. Late-stage (Phase 3) trials may involve up to several thousand patients in up to several hundred clinical sites and may require facilities in several countries. Therefore, the project management required to supervise and control such an extensive program in a compliant manner is substantially larger than early-stage programs. As the need for these resources is not known until some months before the trials begin, it is necessary to recruit large numbers of experienced and talented individuals very quickly. If the labor market does not allow this

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team to be recruited quickly, the sponsor is faced with a decision to delay the program or to initiate it with inadequate management resources. This may result in recruitment of inappropriate patients, inadequate monitoring of clinical investigators and inappropriate handling of data or data analysis. Consequently, it is possible that conclusions of efficacy or safety may not be acceptable to permit filing of a BLA or NDA for any one of the above reasons or a combination of several.

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choose to devote their resources to products that compete with ours. If a collaborator does not successfully develop any one of our products, we will need to find another collaborator to do so. The success of our search for a new collaborator will depend on our legal right to do so at the time and whether the product remains commercially viable.

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If our future drugs fail to achieve market acceptance, we will not be able to generate significant revenues and may never achieve profitability.

Even if any of our drug candidates receive FDA approval, the terms of the approval may limit such drug’s commercial potential. Additionally, even after receipt of FDA approval, such drug would be subject to substantial, ongoing regulatory requirements.

The FDA has complete discretion over the approval of our drug candidates. If the FDA grants approval, the scope of the approval may limit our ability to commercialize such drug, and in turn, limit our ability to generate substantial product revenue. For example, the FDA may grant approval contingent on the performance of costly post-approval clinical trials or subject to warnings or contraindications.contraindications or under a Risk Evaluation and Mitigation Strategy (REMS) drug safety program. Additionally, even after granting approval, the manufacturing processes, labeling, packaging, distribution, adverse event reporting, storage, advertising, promotion and recordkeeping for such drug will be subject to extensive and ongoing regulatory requirements. In addition, manufacturers of our drug candidates are required to comply with cGMP regulations, which include requirements related to quality control and quality assurance as well as the corresponding maintenance of records and documentation. Further, regulatory authorities must inspect and approve these manufacturing facilities before they can be used to manufacture our drug candidates, and these facilities are subject to continual review and periodic inspections by the FDA and other regulatory authorities for compliance with cGMP regulations. If we or a third party discover previously unknown problems with a drug, such as adverse events of unanticipated severity or frequency, or problems with the facility where the drug is manufactured, a regulatory authority may impose restrictions on that product, the manufacturer or us, including requiring withdrawal of the drug from the market or suspension of manufacturing. If we, our drug candidates or the manufacturing facilities for our drug candidates fail to comply with regulatory requirements of the FDA and/or other non-U.S. regulatory authorities, we could be subject to administrative or judicially imposed sanctions, including the following:

The regulatory requirements and policies may change, and additional government regulations may be enacted with which we may also be required to comply. We cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative action, either in the United States or in other countries. If we are not able to maintain regulatory compliance, we may not be permitted to market our future products and our business may suffer.

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Reimbursement decisions by third-party payors may have an adverse effect on pricing and market acceptance of any of our drug candidates. If there is not sufficient reimbursement for our future drugs, it is less likely that such drugs will be widely used.

Market acceptance and sales of any of our drug candidates for which we obtain regulatory approval will depend on reimbursement policies and may be affected by future health care reform measures in both the United States and foreign jurisdictions. Government authorities and third-party payors, such as private health insurers and health maintenance organizations, decide which drugs they will cover and establish payment levels. In addition, government authorities and these third-party payors are increasingly attempting to contain health care costs by demanding price discounts or rebates and limiting both the types and variety of drugs that they will cover and the amounts that they will pay for these drugs. In addition, we might need to conduct post-marketing studies in order to demonstrate the cost-effectiveness of any future drugs to such payors’ satisfaction. Such studies might require us to commit a significant amount of management time and financial and other resources.

Reimbursement rates may vary according to the use of the drug and the clinical setting in which it is used, may be based on payments allowed for lower-cost products that are already reimbursed, may be incorporated into existing payments for other products or services and may reflect budgetary constraints and/or imperfections in Medicare or Medicaid data used to calculate these rates. Net prices for drugs may be reduced by mandatory discounts or rebates required by government health care programs. Such programs, or regulatory changes or relaxation of laws that restrict imports of drugs from other countries, could reduce the net price we receive for any future marketed drugs. In addition, our future drugs might not ultimately be considered cost-effective.

We cannot be certain that reimbursement will be available for any drug candidates that we develop.Also, we cannot be certain that reimbursement policies will not reduce the demand for, or the price paid for, any future drugs. If reimbursement is not available or is available on a limited basis, we may not be able to successfully commercialize any drug candidates that we develop.

Other factors could affect the demand for and sales and profitability of any drug candidates that we may commercialize in the future.

In general, other factors that could affect the demand for and sales and profitability of our future drugs include, but are not limited to:

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Any of these factors could have a material adverse effect on the sales of any drug candidates that we may commercialize in the future.

Failure to obtain regulatory approvals in foreign jurisdictions will prevent us from marketing our products internationally.

We may seek approval for our drug candidates outside the United States and may market future products in international markets. In order to market our future products in the European Economic Area, or EEA, and many other foreign jurisdictions, we must obtain separate regulatory approvals. Specifically, in the EEA, medicinal products can only be commercialized after obtaining a Marketing Authorization, or MA.

Before granting the MA, the European Medicines Agency or the competent authorities of the member states of the EEA make an assessment of the risk-benefit balance of the product on the basis of scientific criteria concerning its quality, safety and efficacy.

The approval procedures vary among countries and can involve additional clinical testing, and the time required to obtain approval may differ from that required to obtain FDA approval. Clinical studies conducted in one country may not be accepted by regulatory authorities in other countries. Approval by the FDA does not ensure approval by regulatory authorities in other countries, and approval by one or more foreign regulatory authorities does not ensure approval by regulatory authorities in other foreign countries or by the FDA. However, a failure or delay in obtaining regulatory approval in one country may have a negative effect on the regulatory process in others. The foreign regulatory approval process may include all of the risks associated with obtaining FDA approval. We may not obtain foreign regulatory approvals on a timely basis, if at all. We may not be able to file for regulatory approvals, and even if we file, we may not receive necessary approvals to commercialize our products in any market.

If we obtain approval to commercialize any approved products outside of the United States, a variety of risks associated with international operations could materially adversely affect our business.

If our drug candidates are approved for commercialization outside of the United States, we expect that we will be subject to additional risks related to international operations and entering into international business relationships, including:

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Risks Related to Reliance on Third Parties

We rely on third parties to plan, conduct and monitor our clinical tests, and their failure to perform as required would interfere with our product development.

We rely on third parties to conduct a significant portion of our clinical development activities. These activities include clinical patient recruitment and observation, clinical trial monitoring, clinical data management and analysis, safety monitoring and project management. We conduct project management and medical and safety monitoring in-house for some of our programs and rely on third parties for the remainder of our clinical development activities. If any of these third parties is unable to perform in a quality and timely manner, and at a feasible cost, our clinical studies will face delays. Further, if any of these third parties fails to perform as we expect or if their work fails to meet regulatory standards, our testing could be delayed, cancelled or rendered ineffective.

We rely on contract manufacturers over whom we have limited control. Should the cost, delivery and quality of clinical materials manufactured by us in our Fall River facility or supplied by contract manufacturers vary to our disadvantage, our business operations could suffer significant harm.

We have limited experience in commercial manufacturing. We rely on CMOs to manufacture drug substance and drug product for any late-stage clinical studies of our drug candidates as well as for future commercial supplies. Our ability to conduct late-stage clinical trials, manufacture and commercialize our drug candidates, if regulatory approval is obtained, depends on the ability of such third parties to manufacture our drug candidates on a large scale at a competitive cost and in accordance with cGMP and foreign regulatory requirements, if applicable. We also rely on CMOs for labeling and storage for studies inside and outside the US. In order for us to establish our own commercial manufacturing facility, we would require substantial additional funds and would need to make facility modifications, hire and retain significant additional personnel and comply with extensive cGMP regulations applicable to such a facility. The commercial manufacturing facility would also need to be licensed for the production of our drug candidates by the FDA and meet other regulatory standards.

Prior to approval of any drug candidate, the FDA must review and approve validation studies for both drug substance and drug product. The manufacturing processes for our drug candidates and immunotherapeutic delivery systems utilize known technologies. We believe that the products we currently have under development can be scaled up to permit manufacture in commercial quantities. However, there can be no assurance that we will not encounter difficulties in scaling up the manufacturing processes. Significant scale-up of manufacturing may result in unanticipated technical challenges and may require additional validation studies that the FDA must review and approve. CMOs may encounter difficulties in scaling up production, including problems involving supply chain, raw material suppliers, production yields, technical difficulties, scaled-up product characteristics, quality control and assurance, shortage of qualified personnel, capacity constraints, changing priorities within the CMOs, compliance with FDA and foreign regulations, environmental compliance, production costs and development of advanced manufacturing techniques and process controls. Any of these difficulties, if they occur and are not overcome to the satisfaction of the FDA or other regulatory agency, could lead to significant delays and possibly the termination of the development program for such drug candidate. These risks become more acute as we scale up for commercial quantities, where a reliable sourcesources of drug substance and drug product becomesbecome critical to commercial success. The commercial viability of any of our drug candidates, if approved, will depend on the ability of our contract manufacturers to produce drug substance and drug product on a large scale. Failure to achieve this level of supply can jeopardize and prevent the successful commercialization of the drug.

We operate our own cGMP manufacturing facility in Fall River, Massachusetts, to produce drug substance for our current and planned early-stage clinical trials. Our Fall River manufacturing facility has 250L and 1000L bioreactor capacity and is able to manufacture in compliance with FDA and EU regulations, allowing us to distribute potential products to clinical sites in the U.S., EU and ROW for early-stage clinical trials. We currently manufacture CDX-0159, CDX-1140, CDX-301, CDX-527have manufactured barzolvolimab and CDX-585 drug substance in our Fall River facility for our current and planned Phase 1 and Phase 2 clinical trials. All products are then filled at CMOs. Any manufacturing failures, supply chain delays or compliance issues at our Fall River facility or at our CMOs could cause delays in our Phase 1 and Phase 2 clinical studies for these drug candidates.

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produce larger batches in support of late-stage trials and to prepare for potential commercialization. We believe that CDX-0159barzolvolimab can be scaled up to permit manufacturing in commercial quantities. However, there can be no assurance that we will not encounter difficulties in scaling up the manufacturing processes.

Our leading drug candidates require specialized manufacturing capabilities and processes. We may face difficulty in securing commitments from U.S. and foreign contract manufacturers as these manufacturers could be unwilling or unable to accommodate our needs. Relying on foreign manufacturers involves peculiar and increased risks, including the risk relating to the difficulty foreign manufacturers may face in complying with cGMP requirements as a result of language barriers, lack of familiarity with cGMP or the FDA regulatory process, supply chain issues or other causes, economic or political instability in or affecting the home countries of our foreign manufacturers, shipping delays, potential changes in foreign regulatory laws governing the sales of our product supplies, fluctuations in foreign currency exchange rates and the imposition or application of trade restrictions.

There can be no assurances that contract manufacturers will be able to meet our timetable and requirements. Further, contract manufacturers must operate in compliance with cGMP and failure to do so could result in, among other things, the disruption of product supplies. As noted above, non-U.S. contract manufacturers may face special challenges in complying with cGMP requirements, and although we are not currently dependent on non-U.S. collaborators or contract manufacturers, we may choose or be required to rely on non-U.S. sources in the future as we seek to develop stable supplies of increasing quantities of materials for ongoing clinical trials of larger scale. Our dependence upon third parties for the manufacture of our products may adversely affect our profit margins and our ability to develop, manufacture, sell and deliver products on a timely and competitive basis.

We may need to rely on third-party collaborators to develop and commercialize companion diagnostic tests for our drug candidates.

We do not have experience or capabilities in developing, administering, obtaining regulatory approval for, or commercializing companion diagnostic tests and will need to rely in large part on third-party collaborators to perform these functions. Companion diagnostic tests are subject to regulation by the FDA and similar regulatory authorities outside of the United States as medical devices and require separate regulatory approval prior to commercialization. We may need to rely on such third-party collaborators to obtain regulatory approval and commercialize such companion diagnostic tests. Such third-party collaborators:

If such third-party collaborators fail to develop, obtain regulatory approval or commercialize the companion diagnostic test, we may not be able to enter into arrangements with another diagnostic company to obtain supplies of an alternative diagnostic test for use in connection with the development and commercialization of our drug candidates or do so on commercially reasonable terms, which could adversely affect and/or delay the development or commercialization of our drug candidates.

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Our reliance on third parties requires us to share our trade secrets, which increases the possibility that a competitor will discover them.

Because we rely on third parties to develop our drug candidates, we must share trade secrets with them.We seek to protect our proprietary technology in part by entering into confidentiality agreements and, if applicable, material transfer agreements, collaborative research agreements, consulting agreements or other similar agreements with our collaborators, advisors, employees and consultants prior to beginning research or disclosing proprietary information. These agreements typically restrict the ability of our collaborators, advisors, employees and consultants to publish data potentially relating to our trade secrets. Our academic collaborators typically have rights to publish data, provided that we are notified in advance and may delay publication for a specified time in order to secure our intellectual property rights arising from the collaboration. In other cases, publication rights are controlled exclusively by us, although in some cases we may share these rights with other parties. We also conduct joint research and development programs which may require us to share trade secrets under the terms of research and development partnership or similar agreements. Despite our efforts to protect our trade secrets, our competitors may discover our trade secrets, either through breach of these agreements, independent development or publication of information including our trade secrets in cases where we do not have proprietary or otherwise protected rights at the time of publication. A competitor’s discovery of our trade secrets would impair our competitive position.

We or the third parties upon whom we depend may be adversely affected by natural disasters and our business continuity and disaster recovery plans may not adequately protect us from a serious disaster.

Any unplanned event, such as flood, fire, explosion, earthquake, extreme weather condition, medical epidemic, including the COVID-19 pandemic, power shortage, telecommunication failure or other natural or manmade accidents or incidents that result in us being unable to fully utilize our facilities, or the manufacturing facilities of our third-party CMOs, could severely disrupt our operations and have a material adverse effect on our business, results of operations, financial condition and prospects. For example, our operations are located primarily on the east coast of the United States, and any adverse weather event or natural disaster, such as a hurricane or heavy snow storm,snowstorm, could have a material adverse effect on a substantial portion of our operations. If any event occurred that prevented us from using all or a significant portion of our manufacturing and lab facilities, that damaged critical infrastructure, such as third-party manufacturing facilities, or that otherwise disrupted operations and travel, it may be difficult or, in certain cases, impossible for us to continue our business for a substantial period of time. The disaster recovery and business continuity plans we have in place may prove inadequate in the event of a serious disaster or similar event. We may incur substantial expenses as a result of the limited nature of our disaster recovery and business continuity plans, which could have a material adverse effect on our business.

Risks Related to Business Operations

We may engage in strategic transactions that could impact our liquidity, increase our expenses and present significant distractions to our management.

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

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

We may expand our clinical development, regulatory and sales and marketing capabilities, and as a result, we may encounter difficulties in managing our growth, which could disrupt our operations.

We expect that if our drug candidates continue to progress in development, we may require significant additional investment in personnel, management systems and resources, particularly in the build out of our commercial capabilities. To date we have hired a core commercial team to plan for potential commercial launches if any of our drug candidates are approved. Over the next several years, we may experience significant growth in the number of our employees and the scope of our operations, particularly in the areas of drug development, regulatory affairs and sales and marketing. To manage this potential future growth, we may continue to implement and improve our managerial, operational and financial systems, expand our facilities and continue to recruit and train additional qualified personnel. Due to our limited financial resources and the limited experience of our management team in managing a company with such anticipated growth, we may not be able to effectively manage the expansion of our operations or recruit and train additional qualified personnel. The physical expansion of our operations may lead to significant costs and may divert our management and business development resources. Any inability to manage growth could delay the execution of our business plans or disrupt our operations.

We may not be able to successfully integrate our existing technology or to modify our technologies to create new immunotherapeutic drugs.

If we are able to integrate our acquired assets and licensed assets with our immunotherapy technologies, we believe these assets will give our immunotherapeutic drugs a competitive advantage. However, if we are unable to successfully integrate licensed assets, or other technologies which we have acquired or may acquire in the future, with our existing technologies and potential products currently under development, we may be unable to realize any benefit from our acquisition of these assets, or other technologies which we have acquired or may acquire in the future, and we may face the loss of our investment of financial resources and time in the integration process.

We believe that our immunotherapy technology portfolio may offer opportunities to develop immunotherapeutic drugs that treat a variety of cancers and inflammatory and infectious diseases by stimulating a patient’s immune system against those diseases. If our immunotherapy technology portfolio cannot be used to create effective immunotherapeutic drugs against a variety of diseases, we may lose all or portions of our investment in development efforts for new drug candidates.

Our internal computer systems, or those of our CROs, CMOs, or other contractors or consultants, may fail or suffer security breaches, which could result in a material disruption of our drug development programs.

Despite the implementation of security measures, our internal computer systems and those of our CROs, CMOs, and other contractors and consultants are vulnerable to damage from cyberattacks, malicious intrusion, computer viruses, unauthorized access, loss of data privacy, natural disasters, terrorism, war and telecommunication, electrical failures or other significant disruption. If such an event were to occur and cause interruptions in our operations, it could result in a material disruption of our drug development programs and commercialization efforts. For example, the loss of clinical study data from completed or ongoing clinical studies for any of our drug candidates could result in delays in our regulatory approval efforts and significantly increase our costs to recover or reproduce the data. Further, the risk of cyber-attacks or other privacy or data security incidents may be heightened due to common, external attempts to attack our information technology systems and data using means such as phishing. To the extent that any disruption or security breach were to result in a loss of or damage to our data or applications or inappropriate disclosure of confidential

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or proprietary information, we could incur liability and the further development or commercialization of our drug candidates could be delayed.

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economy, there can be no assurances that unforeseen future events in the global supply chain, and inflationary pressures, will not have a material adverse effect on our business, financial condition and results of operations.

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We may need to license intellectual property from third parties, and such licenses may not be available or may not be available on commercially reasonable terms.

A third party may hold intellectual property, including patent rights, that are important or necessary to the development of our drug candidates. It may be necessary for us to use the patented or proprietary technology of a third party to commercialize our own technology or drug candidates, in which case we would be required to obtain a license from such third party. A license to such intellectual property may not be available or may not be available on commercially reasonable terms, which could have a material adverse effect on our business and financial condition.

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proprietary information, of a former employer or other third parties. Litigation may be necessary to defend against these claims. If we fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights or personnel. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees.

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Designation as a breakthrough therapy is within the discretion of the FDA. Accordingly, even if we believe one of our product candidates meets the criteria for designation as a breakthrough therapy, the FDA may disagree and instead determine not to make such designation. In any event, the receipt of a breakthrough therapy designation for a product candidate may not result in a faster development process, review or approval compared to drugs considered for approval under conventional FDA procedures and does not assure ultimate approval by the FDA. In addition, even if one or more of our product candidates qualify as breakthrough therapies, the FDA may later decide that the products no longer meet the conditions for qualification or decide that the time period for FDA review or approval will not be shortened.

If our processes and systems are not compliant with regulatory requirements, we could be subject to delays in submitting BLAs, NDAs or restrictions on marketing of drugs after they have been approved.

We currently are developing drug candidates for regulatory approval and are in the process of implementing regulated processes and systems required to obtain and maintain regulatory approval for our drug candidates. Certain of these processes and systems for conducting clinical trials and manufacturing material must be compliant with regulatory requirements before we can apply for regulatory approval for our drug candidates. These processes and systems will be subject to continual review and periodic inspection by the FDA and other regulatory bodies. If we are unable to achieve compliance in a timely fashion or if compliance issues are identified at any point in the development and approval process, we may experience delays in filing for regulatory approval for our drug candidates or delays in obtaining regulatory approval after filing. In addition, any later discovery of previously unknown problems or safety issues with approved drugs or manufacturing processes, or failure to comply with regulatory requirements may result in restrictions on such drugs or manufacturing processes, withdrawal of drugs from the market, the imposition of civil or criminal penalties or a refusal by the FDA and/or other regulatory bodies to approve pending applications for marketing approval of new drugs or supplements to approved applications, any of which could have a material adverse effect on our business. In addition, we are a party to agreements that transfer responsibility for complying with specified regulatory requirements, such as filing and maintenance of marketing authorizations and safety reporting or compliance with manufacturing requirements, to our collaborators and third-party manufacturers. If our collaborators or third-party manufacturers do not fulfill these regulatory obligations, any drugs for which we or they obtain approval may be subject to later restrictions on manufacturing or sale or may even risk withdrawal, which could have a material adverse effect on our business.

We have conducted and are conducting clinical trials outside the United States and anticipate conducting additional clinical trials outside the United States, and the FDA may not accept data from such trials.

We are currently conducting clinical trials for our product candidates in countries outside of the United States and we anticipate that we will conduct additional clinical trials in countries outside the United States. Although the FDA may accept data from clinical trials conducted outside the United States, acceptance of such study data by the FDA is subject to certain conditions. For example, the clinical trial must be conducted in accordance with GCP requirements and the FDA must be able to validate the data from the clinical trial through an onsite inspection if it deems such inspection necessary. Where data from foreign clinical trials are intended to serve as the sole basis for marketing approval in the United States, the FDA will not approve the application on the basis of foreign data alone unless those data are considered applicable to the U.S. patient population and U.S. medical practice, the clinical trials were performed by clinical investigators of recognized competence, and the data is considered valid without the need for an on-site inspection by the FDA or, if the FDA considers such an inspection to be necessary, the FDA is able to validate the data through an on-site inspection or other appropriate means. In addition, such clinical trials would be subject to the applicable local laws of the foreign jurisdictions where the clinical trials are conducted. A description of any studies related to overdosage is also required, including information on dialysis, antidotes, or other treatments, if known. There can be no assurance the FDA will accept data from clinical trials conducted outside of the United States. If the FDA does not accept any such data, it would likely result in the need for additional clinical trials, which would be costly and time-consuming and delay aspects of our development plan.

Risks inherent in conducting international clinical trials include, but are not limited to:

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Changes in product candidate manufacturing or formulation may result in additional costs or delay.

As product candidates are developed through preclinical studies to late-stage clinical trials towards approval and commercialization, it is common that various aspects of the development program, such as manufacturing methods and formulation, are altered along the way in an effort to optimize processes and results. During the course of a development program, sponsors may also change the contract manufacturers used to produce the product candidates. Such changes carry the risk that they will not achieve these intended objectives. Any of these changes could cause our product candidates to perform differently and affect the results of clinical trials. Such changes may also require additional testing, notification or approval by the FDA, EMA or other regulatory authorities. This could delay completion of clinical trials; require the conduct of bridging clinical trials or studies, or the repetition of one or more clinical trials; increase clinical trial costs; delay approval of our product candidates and jeopardize our ability to commence product sales and generate revenue.

Even if we receive regulatory approval for a drug candidate, we will be subject to ongoing regulatory obligations and continued regulatory review, which may result in significant additional expense and subject us to penalties if we fail to comply with applicable regulatory requirements.

Once regulatory approval has been granted, the approved product and its manufacturer are subject to continual review by the FDA and/or non-U.S. regulatory authorities. Any regulatory approval that we or our collaboration partners receive for our drug candidates may be subject to limitations on the indicated uses for which the product may be marketed or contain requirements for potentially costly post-marketing follow-up studies to monitor the safety and efficacy of the product. In addition, if the FDA and/or non-U.S. regulatory authorities approve any of our drug candidates, we will be subject to extensive and ongoing regulatory requirements by the FDA and other regulatory authorities with regard to the labeling, packaging, adverse event reporting, storage, advertising, promotion and recordkeeping for our products. In addition, manufacturers of our drug products are required to comply with cGMP regulations, which include requirements related to quality control and quality assurance as well as the corresponding maintenance of records and documentation. Further, regulatory authorities must inspect and approve these manufacturing facilities before they can be used to manufacture our drug products, and these facilities are subject to continual review and periodic inspections by the FDA and other regulatory authorities for compliance with cGMP regulations. If we or a third party discover previously unknown problems with a product, such as adverse events of unanticipated severity or frequency or problems with the facility where the product is manufactured, a regulatory authority may impose restrictions on that product, the manufacturer or us, including requiring withdrawal of the product from the market or suspension of manufacturing. If we, our drug candidates or the manufacturing facilities for our drug candidates fail to comply with regulatory requirements of the FDA and/or other non-U.S. regulatory authorities, we could be subject to administrative or judicially imposed sanctions, including the following:

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The regulatory requirements and policies may change and additional government regulations may be enacted with which we may also be required to comply. We cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative action, either in the United States or in other countries. If we are not able to maintain regulatory compliance, we may not be permitted to market our future products, and our business may suffer.

We may be subject, directly or indirectly, to federal and state health care fraud and abuse laws, false claims laws, transparency and pricing laws and health information privacy and security laws. If we are unable to comply, or have not fully complied, with such laws, we could face substantial penalties.

If we obtain FDA approval for any of our drug candidates and begin commercializing those products in the United States, our operations will be directly, or indirectly through our customers, subject to various federal and state fraud and abuse laws, including, without limitation, the federal Anti-Kickback Statute and the federal False Claims Act. These laws may affect, among other things, our proposed sales, marketing and education programs. In addition, we may be subject to patient privacy regulation by both the federal government and the states in which we conduct our business. The laws that may affect our ability to operate include:

Although compliance programs can mitigate the risk of investigation and prosecution for violations of these laws, the risks cannot be entirely eliminated. If our operations are found to be in violation of any of the laws described above or any other governmental regulations that apply to us, we may be subject to penalties, including exclusion from payment by federal health care programs, civil and criminal penalties, damages, fines and the curtailment or restructuring of our operations, any of which could adversely affect our ability to operate our business and our results of operations. Moreover, achieving and sustaining compliance with applicable federal and state privacy, security and fraud laws may prove costly.

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Compliance with laws and regulations pertaining to the privacy and security of health information may be time consuming, difficult and costly, particularly in light of increased focus on privacy issues in countries around the world, including the U.S. and the EU.

We are subject to various domestic and international privacy and security regulations.regulations related to personal information, including health information, that are appliable to our business and associated data processing activities. The confidentiality, collection, use and disclosure of personal data, including clinical trial patient-specific information, are subject to governmental regulation generally in the country that the personal data were collected or used. In the United States, we are subject to various state and federal privacy and data security regulations, including but not limited to HIPAA and as amended by the HITECH Act. HIPAA imposes specified requirements relating to the privacy, security and transmission of individually identifiable health information, and mandates, among other things, the adoption of uniform standards for the electronic exchange of information in common health care transactions, as well as standards relating to the privacy and security of individually identifiable health information, which require the adoption of administrative, physical and technical safeguards to protect such information. We may also be subject to state security breach notification laws, state laws protecting the privacy and security of health and personal information, and federal and state consumer protections laws which regulate the collection, use, disclosure and transmission of personal information. These laws may overlap and conflict with each other, and each of these laws is subject to varying interpretations by courts and government agencies, creating complex compliance issues for us. In the EU, personal data includes any information that relates to an identified or identifiable natural person with health information carrying additional obligations, including obtaining the explicit consent from the individual for collection, use or disclosure of the information. We are also subject to the EU General Data Protection Regulation 2016/679 (“GDPR”). Violations of the GDPR can carry hefty fines. In addition, we may be subject to additional national laws and regulations that govern the privacy and security of health information in certain circumstances, many of which came into effect on May 25, 2018.differ from each other in significant ways, thus complicating compliance efforts. If we fail to comply with applicable data protection laws and regulations, we could be subject to penalties or sanctions, including criminal penalties. Furthermore, the legislative and regulatory landscape for privacy and data protection continues to evolve, and there has been an increasing amount of focus on privacy and data protection issues. The United States and the EU and its member states continue to issue new privacy and data protection rules and regulations that relate to personal data and health information.

Compliance with these laws may be time consuming,time-consuming, difficult and costly. If we fail to comply with applicable laws, regulations or duties relating to the use, privacy or security of personal data we could be subject to the imposition of significant civil and criminal penalties, be forced to alter our business practices and suffer reputational harm.

Changes in health care law and implementing regulations, including government restrictions on pricing and reimbursement, as well as health care policy and other health care payor cost-containment initiatives, may have a material adverse effect on us.

In the United States and some foreign jurisdictions, there have been a number of legislative and regulatory changes and proposed changes regarding the regulatory system, health care system and efforts to control health care costs, including drug prices, that could have a significant negative impact on our business, including preventing, limiting or delay regulatory approval of our drug candidates and reducing the sales and profits derived from our products once they are approved. For example, in the United States, the ACA substantially changed the way health care is financed by both governmental and private insurers and significantly affects the pharmaceutical industry. Many provisions of ACA impact the biopharmaceutical industry, including that in order for a biopharmaceutical product to receive federal reimbursement under the Medicare Part B and Medicaid programs or to be sold directly to U.S. government agencies, the manufacturer must extend discounts to entities eligible to participate in the drug pricing program under the Public Health Services Act, or PHS. Since its enactment, there have been judicial and Congressional challenges and amendments to certain aspects of ACA. There is continued uncertainty about the implementation of ACA, including the potential for further amendments to the ACA and legal challenges to or efforts to repeal the ACA.

In addition, the Inflation Reduction Act of 2022, enacted in August 2022, empowers the Centers for Medicare and Medicaid Services to negotiate directly with pharmaceutical companies to set the prices for a limited set of high-cost drugs covered by Medicare, and puts penalties in place for drug manufacturers who increase their Medicare prices by more than the rate of inflation.

Other examples of proposed changes include, but are not limited to, expanding post-approval requirements, changing the Orphan Drug Act, and restricting sales and promotional activities for pharmaceutical products.

We cannot be sure whether additional legislative changes will be enacted, or whether government regulations, guidance or interpretations will be changed, or what the impact of such changes would be on the marketing approvals, sales, pricing, or reimbursement of our drug candidates or products, if any, may be.

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Risks Related to Our Capital Stock

Our history of losses and uncertainty of future profitability make our common stock a highly speculative investment.

We have had no commercial revenue to date from sales of our drug candidates. We had an accumulated deficit of $1.1$1.3 billion as of December 31, 2021.2022. We expect to spend substantial funds to continue the research and development testing of our drug candidates.

In anticipation of FDA approval of these products, we will need to make substantial investments to establish sales, marketing, quality control, regulatory compliance capabilities and commercial manufacturing alliances. These investments will increase if and when any of these drug candidates receive FDA approval. We cannot predict how quickly our lead drug candidates will progress through the regulatory approval process. As a result, we may continue to lose money for several years.

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assets at the time of the ownership change, and such unrealized loss or gain is recognized during the five-year period after the ownership change. Subsequent ownership changes, as defined in Section 382, could further limit the amount of net operating loss carryforwards and research and development credits that can be utilized annually to offset future taxable income. Additionally, as provided above, the Tax Cuts and Jobs Act limited the deduction for net operating losses to 80% of taxable income while providing that net operating loss carryovers for years after 2017 will not expire. The CARES Act provides relief to corporate taxpayers by permitting a five year carryback of 2018 – 2020 NOLs, removing the 80% limitation on the carryback of those NOLs, and accelerates refunds for minimum tax credit carryforwards, along with a few other provisions. During the twelve months ended December 31, 2021,2022, no material adjustments were made to provision amounts recorded as a result of the enactment of the CARES Act.

Refer to Note 15, “Income Taxes,” in the accompanying notes to the financial statements for additional discussion on income taxes.

General Risk Factors

If we fail to maintain an effective system of internal control over financial reporting, we may not be able to accurately report our financial results or prevent fraud. As a result, stockholders could lose confidence in our financial and other public reporting, which would harm our business and the trading price of our common stock.

Effective internal controls over financial reporting are necessary for us to provide reliable financial reports and, together with adequate disclosure controls and procedures, are designed to prevent fraud. Any failure to implement required or improved controls, or difficulties encountered in their implementation, could cause us to fail to meet our reporting obligations. In addition, any failure to maintain effective internal control as a result of shutdowns during the COVID-19 pandemic could result in deficiencies in internal control. We have designed, implemented and tested the internal control over financial reporting required to comply with this obligation, which was and is time consuming, costly, and complicated. A control system, no matter how well designed and operated, can provide only reasonable, not absolute, assurance that the control system’s objectives will be met. Because of the inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that misstatements due to error or fraud will not occur or that all control issues and instances of fraud will be detected. Any testing by us conducted in connection with Section 404 of the Sarbanes-Oxley Act of 2002, or any subsequent testing by our independent registered public accounting firm, may reveal deficiencies in our internal controls over financial reporting that are deemed to be material weaknesses or that may require prospective or retroactive changes to our financial statements or identify other areas for further attention or improvement. Inferior internal controls could also cause investors to lose confidence in our reported financial information, which could have a negative effect on the trading price of our common stock.

We have many competitors in our field, and they may develop technologies that make ours obsolete.

Biotechnology, pharmaceuticals and therapeutics are rapidly evolving fields in which scientific and technological developments are expected to continue at a rapid pace. We have many competitors in the U.S. and abroad. The competitors of which we are aware that have initiated a Phase 3 study or have obtained marketing approval for a potentially competitive drug to CDX-0159barzolvolimab for treatment of CSU, CIndU, or PN and EoE include: Allakos (lirentelimab for EoE), AstraZeneca (Fasenra for CSU), Galderma/Chugai (nemolizumab for PN), Genentech (fenebrutinib for CSU), Leo Pharma (Adbry for AD), Novartis (ligelizumab for CSU, CIndU and food allergy; LOU064remibrutinib for CSU), Regeneron/Sanofi (Dupixent for CSU, CIndU,

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reasonably estimated at this time and our business could be adversely impacted by its effects. In an effort to halt or slow the outbreak of COVID-19, the United States has,many governments have, at times, placed significant restrictions on travel and many businesses have, at times, announced closures for extended closuresperiods which could adversely impact our operations. Enrollment of patients in our clinical trials and our planned and ongoing preclinical and clinical trials may be delayed due to COVID-19. The impact of the COVID-19 pandemic on the operations of the FDA and other health authorities may delay potential approvals of our clinical trial protocols. In addition, we rely on independent clinical investigators, contract research organizations and other third-party service providers to assist us in managing, monitoring and otherwise carrying out our preclinical studies and clinical trials, and the pandemic may affect their ability to devote sufficient time and resources to our programs. We also rely on third party suppliers and contract manufacturers to produce the drug product we utilize in our clinical trials, and the pandemic may cause delays in the delivery of active pharmaceutical ingredients (“APIs”) and drug product. Temporary closure of our facilities, or facilities at which our clinical or preclinical trials are conducted, or restrictions on the ability of our employees, clinicians or patients enrolled in our trials to travel could adversely affect our operations and our ability to conduct and complete our preclinical and clinical trials. In addition, the COVID-19 pandemic, including insufficient vaccination of the general population and the emergence of newCOVID-19 variants, including the delta variant and the omicron variant, could affect the health and availability of our workforce as well as those of the third parties on whom we rely. If new, more infectious or severe variants emerge, it is possible that the impact of the pandemic on our business may increase or lengthen in duration.

As a result of the foregoing factors, the expected timeline for data readouts of our preclinical studies and clinical trials and certain regulatory filings may be negatively impacted, which would adversely affect our business.

We depend greatly on the intellectual capabilities and experience of our key executives and scientists, and the loss of any of them could affect our ability to develop our products.

The loss of any of our executive officers could harm us. We entered into employment agreements with each of our executive officers, although an employment agreement as a practical matter does not guarantee retention of an employee. We also depend on our scientific and clinical collaborators and advisors, all of whom have outside commitments that may limit their availability to us. In addition, we believe that our future success will depend in large part upon our ability to attract and retain highly skilled scientific, managerial and marketing personnel, particularly as we expand our activities in clinical trials, the regulatory approval process and sales and manufacturing. We routinely enter into consulting agreements with our scientific and clinical collaborators and advisors, key opinion leaders and heads of academic departments in the ordinary course of our business. We also enter into contractual agreements with physicians and institutions who recruit patients into our clinical trials on our behalf in the ordinary course of our business. Notwithstanding these arrangements, we face significant competition for this type of personnel from other companies, research and academic institutions, government entities and other organizations. We cannot predict our success in hiring or retaining the personnel we require for continued growth.

Our employees may engage in misconduct or other improper activities, including noncompliance with regulatory standards and requirements, which could have a material adverse effect on our business.

We are exposed to the risk of employee fraud or other misconduct. Misconduct by employees could include intentional failures to comply with FDA regulations, provide accurate information to the FDA, comply with applicable privacy laws, comply with manufacturing standards we have established, comply with federal and state health care fraud and abuse laws and regulations, report

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We may not be able to maintain compliance with the Listing Rules of the NASDAQ Stock Exchange.

There can be no assurance that in the future we will be able to maintain compliance with the Nasdaq Listing Rules, including the minimum bid price requirement and other applicable corporate governance requirements. If we fail to maintain compliance with the minimum bid requirement or to meet the other applicable continued listing requirements for the NASDAQ Capital Market in the future and NASDAQ determines to delist our common stock, the delisting could adversely affect the market price and liquidity of our common stock and reduce our ability to raise additional capital. In addition, if our common stock is delisted from NASDAQ and the trading price remains below $5.00 per share, trading in our common stock might also become subject to the requirements of certain rules promulgated under the Exchange Act, which require additional disclosure by broker-dealers in connection with any trade involving a stock defined as a “penny stock” (generally, any equity security not listed on a national securities exchange or quoted on NASDAQ that has a market price of less than $5.00 per share, subject to certain exceptions).

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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, 2021,2022, we incurred an aggregate of $301.1$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 2020 and 2019.2020. The amounts disclosed in the

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Clinical Development Programs

The COVID-19 pandemic continuesBarzolvolimab (also referred to have a major impact in the US and around the world. The availability of vaccines holds promise for the future, though new variants of the virus and potential waning immunity from vaccines may result in continued impact from this pandemic in the future, which could adversely impact our operations. To date, the Company has managed delays and disruptions without significant impact in planned and ongoing preclinical and clinical trials, manufacturing or shipping. Potential impacts to our business include delays in planned and ongoing preclinical and clinical trials including enrollment of patients, disruptions in time and resources provided by independent clinical investigators, contract research organizations, and other third-party service providers, temporary closures of our facilities, disruptions or restrictions on our employees’ ability to travel, and delays in manufacturing and/or shipments to and from third-party suppliers and contract manufacturers for APIs and drug product.

CDX-0159as CDX-0159)

CDX-0159Barzolvolimab 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. CDX-0159Barzolvolimab is designed to block KIT activation by disrupting both SCF binding and KIT dimerization. Celldex believesWe believe that by targeting KIT, CDX-0159barzolvolimab 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”)(CSU), also known as chronic idiopathic urticaria (“CIU”)(CIU), and chronic inducible urticaria (“CIndU”)(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 CDX-0159barzolvolimab in healthy subjects (n=(n = 32; 8 subjects per cohort, 6 CDX-0159;barzolvolimab; 2 placebo). Subjects received a single intravenous infusion of CDX-0159barzolvolimab 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. CDX-0159Barzolvolimab 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 CDX-0159barzolvolimab 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. The prevalence ofPhase 1 studies in CSU and CIndU is approximately 0.5-1% of the total population or upare 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 3 million patientsinitiate a Phase 2 study in eosinophilic esophagitis in the United States alone (Weller et al. 2010. Hautarzt. 61(8), Bartlett et al. 2018. DermNet. Org). 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. AboutCSU 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 or leukotriene receptor antagonists.antihistamines. Omalizumab, an IgE inhibitor, provides relief for roughly half of the remaining antihistamine/leukotrieneantihistamine refractory patients. Consequently, there is a need for additional therapies. CIndUs are forms of urticaria that have an attributable cause or trigger associated with them, typically resulting in hives or wheals. Celldex is exploring cold-induced, dermographism (scratch-induced) and cholinergic (exercise-induced) urticarias.

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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 second 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 CDX-0159barzolvolimab in patients with cold urticaria (n=10)(ColdU) or symptomatic dermographism (n=10)(SD). In March and June 2021, respectively, we added a third cohort (single dose, 3 mg/kg) in patients with cholinergic urticaria (n=10) and a fourth cohort at a lower dose (single dose, 1.5 mg/kg) in cold urticaria.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. CDX-0159Barzolvolimab is administered intravenously on Day 1 as add on treatment to H1-antihistamines.

In July of 2021, we reported positive interimNovember 2022, data from the cold urticariaColdU and symptomatic dermographism cohorts. As of the data cut-off on June 11, 2021, 20 patients had receivedSD cohorts treated with a single intravenous infusion of CDX-0159barzolvolimab at 3 mg/kg including 11 patients with cold urticaria and 9 patients with symptomatic dermographism. Patients had high disease activity as assessed by provocation threshold testing. In patients with cold urticaria and symptomatic dermographism baseline critical temperature thresholds were 18.9°C/66°F (range: 5-27°C/41-80.6°F) and FricTest® thresholds were 3.8 (range: 3-4) of 4 pins.published in Allergy (Terhorst-Molawi et al Allergy. 2022 Nov 16. doi: 10.1111/all.15585). Safety results were reported for all 2021 patients; activity results were reported for the 1920 patients who received a full dose of CDX-0159. 14barzolvolimab. 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 19quality of life (QoL) and poorly controlled disease, respectively. Three patients completed the 12-week study observation period(1 with ColdU and five2 with SD) were ongoing (range of 2-8 weeks) as of June 11, 2021.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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In SeptemberTo date, 19 of 2021, we reported additional positive data from the study on measurements of symptom control and quality of life. A19 (100%) patients with cold urticaria treated with either a single dose of CDX-0159 (3barzolvolimab at 1.5 or 3.0 mg/kg) resultedkg 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 rapidPhase 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 sustained improvementsafety 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 control and greatly reduced disease impact90 patients with symptomatic dermographism will be randomly assigned on qualitya 1:1:1 ratio to receive subcutaneous injections of life, as measured bybarzolvolimab 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 Urticaria Control Test (UCT)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 Dermatology Life Quality Index (DLQI)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).

Celldex hasPrurigo Nodularis (PN)

We have expanded clinical development of CDX-0159barzolvolimab into prurigo nodularis (“PN")(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 areis currently noonly one FDA approved therapiestherapy 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 CDX-0159barzolvolimab in up to 30 patients with PN.

Manufacturing activities Enrolling an intravenous, early stage study in the dermatology setting has been a challenge and the study has taken longer than expected to supportcomplete. 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 introductioncompletion of the CDX-0159 subcutaneous formulation into24 week follow up period post dosing for patients on study, we plan to present data from the clinical program have been completed and,study in September 2021, we initiated dosingthe second half of 2023. Potential future development in a randomized, double-blind, placebo-controlled, Phase 1 study designed to evaluate the safety of single ascending doses ofPN will utilize the subcutaneous formulation of CDX-0159 in healthy volunteers. In February 2022, we reported that subcutaneous administration of CDX-0159 was well tolerated and that multiple dose levels have been identified that possess promising pharmacokinetic and pharmacodynamic properties. Importantly, subcutaneous delivery of CDX-0159 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. Celldex anticipates the upcoming Phase 2 multi-dose studies in urticaria will evaluate 75mg and 150mg administered q4weeks and 300mg administered q8weeks. The planned doses support a 0.5 to 2 ml injection volume, allowing for a single injection as CDX-0159 advances towards potential commercialization. In 2022, we plan to initiate a transfer of our current CDX-0159 manufacturing process to a contract manufacturing organization to support late-stage trials and to prepare for potential commercialization.barzolvolimab.

In February 2022, we also reported interim data after completing the in-life dosing portion of our six month chronic toxicology study in non-human primates; a subset of the animals will continue to be followed beyond clearance of the CDX-0159 antibody to study completion. As expected and consistent with other KIT-targeting agents, impact on spermatogenesis was observed which is anticipated to be fully reversible upon clearance of the antibody. There were no other clinically adverse findings reported in the study. Celldex believes these data strongly support the Company’s planned Phase 2 studies in urticaria later this year and in future indications.Eosinophilic Esophagitis (EoE)

In February 2022, we announced that we will be expanding clinical development of CDX-0159barzolvolimab into eosinophilic esophagitis (“EoE”)(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 are limited treatment options for EoE. Individuals often participate in an elimination diet to identify potential food allergens that may contribute to EoE, avoid difficult to swallow foods and undergo esophageal dilation. While notis only one FDA approved therapy for EoE, proton pump inhibitors and the swallowingrepresenting an area of topical corticosteroids are also used to address the disease.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 CDX-0159’sbarzolvolimab’s potential as a mast cell depleting agent, we believe EoE is an important indication for future study.

We continuestudy and plan to initiate a Phase 2 multi-center, randomized, double-blind, placebo-controlled subcutaneous study designed to assess potential opportunities for CDX-0159the treatment effects and safety of barzolvolimab in other diseases where mast cells play an important role, such as dermatologic, respiratory, allergic, gastrointestinal and ophthalmic conditions.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. Potent CD40 agonist antibodies have shown encouraging results in early clinical studies; however, systemic toxicity associated with broad CD40 activation has limited their dosing concentrations to levels that may not be optimal for engaging CD40 expressing cells in the tumor microenvironment. CDX-1140 has unique properties relative to other CD40 agonist antibodies: potent agonist activity is independent of Fc receptor interaction, contributing to more consistent, controlled immune activation; CD40L binding is not blocked, leading to potential synergistic effects of agonist activity near activated T cells in lymph nodes and tumors; and the antibody does not promote cytokine production in whole blood assays. CDX-1140 has shown direct anti-tumor activity in preclinical models of lymphoma. Preclinical studies of CDX-1140 clearly demonstrate strong immune activation effects and low systemic toxicity and support the design of theA Phase 1 study to identify the dose for characterizing single-agent and combination activity.

In November 2017, we initiated a Phase 1 study of CDX-1140was conducted in up to 260 patients with recurrent, locally advanced or metastatic solid tumors and B cell lymphomas. The study is designed to determine the maximum tolerated dose, orAn MTD during a dose-escalation phase (0.01 to 3.0 mg/kg once every four weeks until confirmed progression or intolerance) and to recommend a dose level for further study in a subsequent expansion phase. Secondary objectives include assessments of safety and tolerability, pharmacodynamics, pharmacokinetics, immunogenicity and additional measures of anti-tumor activity, including clinical benefit rate. We believe that the potential for CDX-1140 will be best defined in combination studies with other immunotherapies or conventional cancer treatments. A combination cohort with CDX-301, a hematopoietic cytokine that uniquely expands dendritic cells and hematopoietic stem cells and a safety run-in combination cohort with gemcitabine/nab-paclitaxel in patients with previously untreated metastatic pancreatic adenocarcinoma have been completed. A combination of CDX-1140 with pembrolizumab has completed the safety run-in phase. Expansion cohorts in patients with checkpoint-refractory/resistant squamous cell head and neck cancer and non-small cell lung cancer are enrolling patients.

In November 2020, we reported interim Phase 1 data from patients treated at the maximum tolerated dose (MTD) and recommended dose of 1.5 mg/kg—one of the highest systemic dose levels in the CD40 agonist class. Interim data from the study were presented at the Society for Immunotherapy of Cancer’s (SITC) 35th Annual Meeting 2020 (n=41; 25 mono, 16 with CDX-301kg was established and 29 with post-treatment scans). Preliminary safety data from the combination cohort with pembrolizumab (n=9; 4 at 0.72 mg/kg and 5 at 1.5 mg/kg CDX-1140) were also presented. CDX-1140clinical activity was observed both as a monotherapy and in combination with pembrolizumab was generally well tolerated with mostly grade 1 or 2 drug related adverse events. Activity at 1.5mg/kg dosepembrolizumab. Despite evidence of clinical benefit, questions remain to be answered about CDX-1140, included an ongoing complete response (CR; 18 months as of Oct 2021) in a patient with follicular lymphoma treated with CDX-1140 monotherapy. There was notable tumor shrinkage and/or necrosis in 6 patients with squamous cell head and neck cancer (SCCHN) treated with CDX-1140 alone or in combination with CDX-301 and stable disease (n=10) for 11 to 32 weeks. CDX-1140 provided good systemic exposure and resulted in marked changes in the tumor microenvironment.

In November 2021, we provided an update on the ongoing Phase 1 study. Emerging data from the safety run-in cohort of CDX-1140 with gemcitabine/nab-paclitaxel in patients with previously untreated metastatic pancreatic adenocarcinoma and externalbroader CD40 agonist data recently reported usingclass, regarding the same regimen, suggest that simultaneous treatment with chemotherapybest clinical settings, regimens, and CD40 activation may not be optimal. Alternative strategies for investigating CDX-1140possible combinations before advancing into additional Celldex-sponsored studies. Given our pipeline priorities and resource requirements, in pancreatic cancer in other regimens are being explored, including through investigator sponsored studies. The combinationAugust of CDX-1140 with pembrolizumab has completed the safety run-in phase. Expansion cohorts in patients with checkpoint-refractory/resistant squamous cell head and neck cancer and non-small cell lung cancer are enrolling patients. Of the six patients with squamous cell head and neck cancer treated with CDX-1140 at 1.5 mg/kg in combination with pembrolizumab, encouraging preliminary results have been observed including a confirmed partial response and durable stable disease. Of the six evaluable patients with non-small cell lung cancer, four have had stable disease as their best response. Adverse events, such as arthralgia, myalgia and fatigue, have occurred more frequently in combination with pembrolizumab relative to CDX-1140 monotherapy and the protocol has been amended to allow CDX-1140 dose reduction, if necessary, to help manage these toxicities. Enrollment to the study is ongoing.

CDX-527

CDX-527 is the first candidate from Celldex’s bispecific antibody platform. Bispecifics provide opportunities to engage two independent pathways involved in controlling immune responses to tumors. CDX-527 uses Celldex’s 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

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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-downwritten 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

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Each IPR&D asset is assessed for impairment at least annually or when impairment indicators are present. DuringThe Company has the fourth quarter of 2020, we decided that although we had developed promising data for the AxL target within the TAM program, we would focus our efforts on out-licensing opportunities for the TAM program. As a result, we evaluated the TAM program IPR&D asset for potential impairment dueoption to the change in projected development and regulatory timelines relatedassess qualitative factors to the program and recorded a non-cash partial impairment charge of $14.5 million for the fourth quarter of 2020. During the third quarter of 2021, we evaluated our out-licensing progress since December 31, 2020 and the status and expectation for the TAM program. Despite our efforts to out-license, there was a lack of interest in the program from third parties. Therefore, we evaluated the TAM program IPR&D asset for potential impairment using a discounted cash flow fair value model and concluded that the TAM IPR&D asset was fully impaired. A non-cash impairment charge of $3.5 million was recorded during the third quarter of 2021. 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. We performed an annual impairment test of the remaining IPR&D assets during the fourth quarter of 2021 and concludeddetermine if it is more likely than not that the IPR&D assets were not impaired.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