CLDX US Equity☆

CELLDEX THERAPEUTICS, INC._December 31, 2025

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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, 2025

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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 Jersey08827

(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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Common Stock, par value $.001 ​ CLDX ​ NASDAQ Capital Market

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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, 2025 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 13, 2026 was 66,566,346 shares.

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DOCUMENTS INCORPORATED BY REFERENCE

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Portions of the definitive Proxy Statement for our 2026 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, 2025

TABLE OF CONTENTS

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Part I ​ ​ ​ ​

Item 1. ​ Business ​ 1

Item 1A. ​ Risk Factors ​ 26

Item 1B. ​ Unresolved Staff Comments ​ 57

Item 1C. ​ Cybersecurity ​ 57

Item 2. ​ Properties ​ 58

Item 3. ​ Legal Proceedings ​ 58

Item 4. ​ Mine Safety Disclosures ​ 58

Part II ​ ​ ​ ​

Item 6. ​ [Reserved] ​ 59

Item 7A. ​ Quantitative and Qualitative Disclosures About Market Risk ​ 81

Item 8. ​ Financial Statements and Supplementary Data ​ 82

Item 9A. ​ Controls and Procedures ​ 105

Item 9B. ​ Other Information ​ 106

Part III ​ ​ ​ ​

Item 10. ​ Directors, Executive Officers and Corporate Governance ​ 107

Item 11. ​ Executive Compensation ​ 107

Item 14. ​ Principal Accountant Fees and Services ​ 107

Part IV ​ ​ ​ ​

Item 15. ​ Exhibits, Financial Statement Schedules ​ 108

Signatures ​ ​ ​ 112

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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:

● our dependence on product candidates that are still in development stages;

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● the factors listed under “Risk Factors” in this Annual Report on Form 10-K.

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 exploring the science of mast cell biology and developing therapeutic antibodies which have the ability to engage the human immune system and/or directly affect critical pathways to improve the lives of patients with severe inflammatory, allergic, autoimmune and other devastating diseases. Our drug candidates include monoclonal and bispecific antibodies designed to address mast cell mediated diseases for which available treatments are inadequate.

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

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More detail on these programs is provided in the Clinical Development Programs section.

Our mission 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.

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.”

Clinical Development Programs

Barzolvolimab (also referred to as CDX-0159)

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

Barzolvolimab was initially studied in chronic spontaneous urticaria (CSU) and chronic inducible urticaria (CIndU), diseases where mast cell degranulation plays a central role in the onset and progression of the disease. In July 2024, we initiated two Phase 3 studies in CSU. In February 2026, we announced that enrollment is complete in the Phase 3 studies and that topline data is expected in the fourth quarter of 2026. In November 2023, we reported that barzolvolimab achieved the primary efficacy endpoint in a Phase 2 study in CSU, with a statistically significant mean change from baseline to Week 12 of UAS7 (weekly urticaria activity score) compared to placebo and was well tolerated. In September 2024, we presented 52 week treatment data from the CSU study, demonstrating sustained and deepening disease efficacy and a well tolerated long term safety profile. In June 2025, we presented follow up data from this study through Week 76, 7 months after the completion of dosing with barzolvolimab, demonstrating ongoing profound, sustained complete response and improved quality of life. The study is complete. In April 2024, we announced enrollment was complete in the ongoing Phase 2 CIndU study. In July 2024, we announced that our Phase 2 study in CIndU achieved the primary efficacy endpoint, (statistically significant difference between the percent of patients with a negative provocation test compared to placebo at Week 12) and was well tolerated. 12 week data from the CIndU study were presented in October of 2024 and all secondary endpoints across the study were also met and were highly statistically significant and clinically meaningful. Patients on study continued to receive barzolvolimab for 20 weeks of treatment and were then followed for up to 24 additional weeks without treatment. In November 2025, data from the 20 week placebo controlled treatment period were presented, demonstrating sustained efficacy and a favorable safety profile. Patients with returning or continuing symptoms were eligible to enroll into an open label extension (OLE). The study is now complete.

Based on the positive results reported in urticaria, we expanded development of barzolvolimab into additional indications where mast cells are believed to play an important role. We are conducting ongoing Phase 2 studies in prurigo nodularis (PN) and atopic dermatitis (AD). 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.

Chronic Spontaneous Urticaria (CSU) Summary of Phase 1 and Phase 2 Data Presented to Date

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. It is one of the most frequent dermatologic diseases with a prevalence of 0.5-1.0% of the total population or up to approximately 1 to 3 million patients in the United States (Weller et al. 2010. Hautarzt. 61(8), Bartlett et al. 2018. DermNet.Org). Approximately 50% of patients with CSU achieve symptomatic control with antihistamines. Omalizumab, an IgE inhibitor, provides relief for roughly half of the remaining antihistamine refractory patients. Consequently, there is a need for additional therapies.

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We have completed a Phase 1b randomized, double-blind, placebo-controlled multi-center study of barzolvolimab in CSU. The study was designed to assess the safety of multiple ascending doses of barzolvolimab in patients with CSU who remain symptomatic despite treatment with antihistamines. Secondary and exploratory objectives included pharmacokinetic and pharmacodynamic assessments, clinical activity outcomes and quality of life assessments. Barzolvolimab was administered intravenously as add on treatment to H1-antihistamines, either alone or in combination with H2-antihistamines and/or leukotriene receptor agonists. 45 patients with moderate to severe CSU refractory to antihistamines were 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].

At saturating doses (1.5 mg/kg and higher), barzolvolimab resulted in rapid, marked and durable responses in patients with moderate to severe CSU refractory to antihistamines. The 1.5 mg/kg, 3.0 mg/kg and 4.5 mg/kg dose groups showed similar markedly improved urticaria symptoms, including rapid onset of responses (as early as 1 week after the first dose) and prolonged disease control with sustained durability up to 24 weeks. Patients with prior omalizumab therapy also had similar symptom improvement as all patients.

Phase 1 CSU: Summary of Clinical Activity Assessments at Week 12 & 24

Mean Reduction Baseline UAS7; % at Week 12 82% (n=9) 67% (n=9) 67% (n=8)

Mean Reduction Baseline UAS7; % at Week 24 77% (n=7) 70% (n=6) 80% (n=7)

UAS7=0 (Complete Control); % at Week 12 67% 44% 57%

UAS7=0 (Complete Control); % at Week 24 43% 67% 57%

UCT ≥ 12 (Well-controlled); % at Week 12 89% 63% 75%

UCT ≥ 12 (Well-controlled); % at Week 24 67% 67% 75%

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During post-treatment follow up, 71% (10 of 14) of patients who had been treated with doses greater than or equal to 1.5 mg/kg and had a complete response (UAS7=0) at Week 12, remained urticaria free at Week 24 (patients received last dose of barzolvolimab at Week 8). Profound and durable improvement in angioedema symptoms as measured through the weekly angioedema activity score (AAS7) was achieved across all dose levels evaluated with sustained activity observed with the 1.5 mg/kg and greater dose levels. Patients also reported improvements in quality of life outcomes as assessed by the Dermatology Life Quality Index (DLQI) which surveys patients’ perceptions of symptoms and feelings, daily activities, leisure, work and school performance, personal relationships and treatment.

Tryptase suppression, indicative of mast cell depletion, paralleled symptom improvement, demonstrating the impact of mast cell depletion on CSU disease activity.

Barzolvolimab was well tolerated. Most adverse events were mild or moderate in severity and resolved while on study. The most common treatment emergent adverse events were hair color changes, COVID-19, headache, neutropenia and urinary tract infections (UTIs). UTIs and COVID-19 were reported as unrelated to treatment. Generally transient, asymptomatic and mild changes in hematologic parameters were observed, consistent with observations from prior studies. No pattern of further decrease was observed with multiple dose administration.

Data from this study were reported across multiple medical meetings, including the American Academy of Allergy, Asthma & Immunology (AAAAI) Annual Meeting in February 2023, the European Academy of Allergy and Clinical Immunology (EAACI) Annual Congress in June 2023 and the European Academy of Dermatology & Venereology (EADV) Congress in October 2023.

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We have completed a Phase 2 study in patients with CSU who remained symptomatic despite antihistamine therapy. The study was conducted at approximately 75 sites across 9 countries. The study was a randomized, double-blind, placebo-controlled, parallel group Phase 2 study that evaluated the efficacy and safety profile of multiple dose regimens of barzolvolimab to determine the optimal dosing strategy. 208 patients were 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. After 16 weeks, patients then entered a 36-week active treatment period, in which patients receiving placebo or the 75 mg dose were randomized to receive barzolvolimab 150 mg every 4 weeks or 300 mg every 8 weeks; patients already randomized to the 150 mg and 300 mg treatment arms remained on the same regimen as during the placebo-controlled treatment period. After 52 weeks, patients then entered a follow-up period for an additional 24 weeks. The primary endpoint of the study was mean change in baseline to Week 12 in UAS7 (weekly urticaria activity score). Secondary endpoints included safety and other assessments of clinical activity including ISS7 (weekly itch severity score), HSS7 (weekly hive severity score) and AAS7 (weekly angioedema activity score).

Topline data from this study were presented in November of 2023 and 12 week treatment results were presented at the AAAAI Annual Meeting in February 2024. Data from the 208 patients randomized in the study showed that barzolvolimab achieved the primary efficacy endpoint, with a statistically significant mean change from baseline to Week 12 in UAS7 compared to placebo at all dose levels. Secondary and exploratory endpoints in the study were also achieved at Week 12 and strongly support the primary endpoint results, including changes in ISS7 and HSS7 and responder analyses. Importantly, barzolvolimab demonstrated rapid, durable and clinically meaningful responses in patients with moderate to severe CSU refractory to antihistamines, including patients with prior omalizumab treatment. Demographics and baseline disease characteristics were well balanced across treatment groups. The majority of patients on study had severe disease (UAS7≥28).

Phase 2 CSU: Summary of Clinical Activity Assessments at Week 12

UAS7 Changes

HSS7 Changes

ISS7 Changes

Responder Analyses/Clinical Responses

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UAS7, HSS7 and ISS7 data were analyzed using ANCOVA model and multiple imputation.

Barzolvolimab demonstrated strong improvement in UAS7 independent of omalizumab status at Week 12. Approximately 20% (n=41) of enrolled patients received prior treatment with omalizumab and more than half of these patients had omalizumab-refractory disease. These patients experienced a similar clinical benefit as the overall treated population within their individual dosing groups consistent with the barzolvolimab mechanism of action.

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Barzolvolimab was well tolerated with a favorable safety profile. Most adverse events were mild to moderate in severity; through 12 weeks, the most common treatment emergent adverse events in barzolvolimab treated patients were urticaria/CSU (10%), hair color changes (9%), and neutropenia/ANC decrease (8%). The rate of infections was similar between barzolvolimab treated patients and placebo with no association between neutropenia and infections.

In June 2024, 12 week data on a secondary endpoint from the study, angioedema activity, and additional measures of angioedema control, were presented at the EAACI 2024 Congress. Approximately 72% of patients on study had angioedema at baseline. Barzolvolimab demonstrated significant improvements in AAS7 in patients with angioedema across all doses at Week 12. This improvement was rapid (within 2 weeks) and durable (continued through 12 weeks). Barzolvolimab demonstrated strong improvement in AAS7 independent of omalizumab status at Week 12. Patients on barzolvolimab experienced a > 8 point improvement in AAS7 (considered a clinically meaningful result) across all doses compared to placebo (p<0.05). Barzolvolimab increased angioedema free days compared to placebo through 12 weeks. Patients in the 300 mg cohort were angioedema free 77% of the time over the 12 week period.

Patients on study continued to receive barzolvolimab for up to 52 weeks. Long term treatment data were presented in September at the European Academy of Dermatology & Venereology (EADV) Congress 2024 and quality of life data were presented in March at the AAAAI Annual Meeting 2025. The data demonstrated a sustained and deepening disease efficacy, a well tolerated safety profile, greatly improved urticaria control and reduced disease impact on quality of life over a 52 week treatment period. Key highlights included:

In June of 2025, 52 week data on angioedema activity and additional measures of angioedema control were presented at the EAACI 2025 Congress. Barzolvolimab continued to demonstrate robust, durable and deepening improvements in angioedema symptoms over the treatment period. At Week 52, an 86% mean reduction from baseline was reported for 150 mg Q4W arm and an 82% reduction was reported for the 300 mg Q8W. Up to 77% of patients treated with barzolvolimab who had angioedema at baseline were angioedema free (AAS7=0) at Week 52, which we subsequently announced remained at up to 64% seven months after last dose. Patients treated with barzolvolimab were angioedema free up to 72% of the time over the 52 week treatment period. Up to 87% of patients reported clinically meaningful improvement (>8 point) in AAS7 at Week 52.

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In June of 2025, long term follow up data from the Phase 2 CSU study were presented at the EAACI 2025 Congress. At Week 76, seven months after completion of dosing, patients continue to experience profound clinical benefit on study. Key highlights included:

In September at EADV 2025, data were presented demonstrating rapid and strong efficacy regardless of baseline immunoglobulin E (IgE) levels. In November 2025, at the American College of Allergy, Asthma & Immunology’s Annual Scientific (ACAAI) Meeting, data were presented demonstrating that barzolvolimab leads to rapid and profound improvements in UCT7 scores with sustained disease control off treatment.

We believe these results strongly support the further development of barzolvolimab in CSU. In July 2024, we initiated two Phase 3 studies of barzolvolimab in CSU. The studies, EMBARQ-CSU1 and EMBARQ-CSU2, are designed to establish the efficacy and safety of barzolvolimab in adult patients with CSU who remain symptomatic despite H1 antihistamine treatment. Both Phase 3 trials are randomized, double-blind, placebo-controlled, parallel group, global studies (approximately 40 countries; 250 sites per study) where approximately 915 patients per trial will be randomized evenly to barzolvolimab 150 mg every 4 weeks (following 300 mg loading dose), barzolvolimab 300 mg every 8 weeks (following 450 mg loading dose) or placebo for 52 weeks. At 24 weeks, patients on placebo will be re-randomized to active treatment across both dosing groups. After completion of the 52 week treatment period, patients on study will continue to be followed for 16 weeks. The primary endpoint of the studies will evaluate the clinical effect of barzolvolimab in reducing urticaria activity (weekly urticaria activity score; UAS7) at Week 12. The studies are designed to detect a clinically meaningful difference between each of the active arms versus placebo in the overall population as well as in the subpopulation of omalizumab refractory participants. The primary endpoint analysis will be performed when all patients have completed the placebo controlled portion of the study at 24 weeks. Enrollment to the studies was completed in February 2026 and topline data will be available in Q4 2026. 1,939 patients were enrolled—the largest program conducted in antihistamine refractory CSU, including patients with advanced therapy experienced/refractory CSU. The studies included 43 countries and over 500 sites.

In addition, a global Phase 3b long term extension (LTE) study has been established for patient entry after completion of the EMBARQ - CSU Phase 3 trials. The study will consist of 2 Groups: Group 1 (Observation Group), containing patients whose disease remains well controlled (UAS7<16) and Group 2 (Barzolvolimab Retreatment Group) containing patients whose disease is currently moderate to severe (UAS7≥16). Patients in Group 2 will receive up to an additional year of treatment with barzolvolimab. Patients in the observation group (Group 1) whose CSU flares to a UAS7>/=16 in the first 6 months of the LTE will also be able to receive treatment.

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Chronic Inducible Urticaria (CIndU) Summary of Phase 1 and Phase 2 Data Presented to Date

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 completed a Phase 1b open label clinical trial in patients with CIndU refractory to antihistamines, conducted in Germany. This study was designed to evaluate the safety of a single intravenous dose (3 mg/kg) of barzolvolimab in patients with cold urticaria (ColdU) or symptomatic dermographism (SD). The study was expanded to include a cohort (single dose, 3 mg/kg) in patients with cholinergic urticaria (“CholU”) and a cohort at a lower dose (single dose, 1.5 mg/kg) in ColdU. Patient’s symptoms were induced via provocation testing that resembles real life triggering situations. Secondary and exploratory objectives included pharmacokinetic and pharmacodynamic assessments, including changes from baseline provocation thresholds, measurement of tryptase and stem cell factor levels, clinical activity outcomes, quality of life assessments and measurement of tissue mast cells through skin biopsies.

Generally patients on study had high disease activity at baseline that was poorly controlled and marked impairment in quality of life. At 3 mg/kg in the ColdU and SD cohorts, safety results were reported for 21 patients and activity results were reported for the 20 patients who received a full dose of barzolvolimab. At 1.5 mg/kg in the ColdU cohort, safety results were reported for 10 patients and activity results were reported for the 9 patients who received a full dose of barzolvolimab. At 3 mg/kg in the cholinergic cohort, safety results were reported for 21 patients and activity results were reported for the 20 patients who received a full dose of barzolvolimab.

Rapid (as early as 1 week) and durable responses were observed in patients as assessed by provocation testing.

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Data from this study were reported in Allergy (Nov 2022) and across multiple medical meetings, including the GA2LEN Global Urticaria Forum (GUF) in December and the European Academy of Allergy and Clinical Immunology (EAACI) Annual Congress in June 2022.

We recently completed a Phase 2 study in patients with CIndU who remain symptomatic despite antihistamine therapy. The study was conducted at approximately 85 sites across approximately 12 countries. The randomized, double-blind, placebo-controlled, parallel group Phase 2 study evaluated the efficacy and safety profile of multiple dose regimens of barzolvolimab in patients with CIndU to determine the optimal dosing strategy. 196 patients in 2 cohorts (differentiated by CIndU subtype) including 97 patients with cold urticaria and 99 patients with symptomatic dermographism were 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 then entered a follow-up phase for an additional 24 weeks. In addition, the study included the option for patients who had symptoms following the treatment phase, including patients who were on placebo, to enroll in an open label extension where all patients received 300 mg of barzolvolimab every 8 weeks. The primary endpoint of the study was the percentage of patients with a negative provocation test at Week 12. Secondary endpoints included 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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Topline primary endpoint data from this study were reported in July 2024 and 12 week treatment results were presented at the American College of Allergy, Asthma & Immunology’s Annual Scientific Meeting. Data from the 193 patients randomized and treated in the study showed that barzolvolimab achieved the primary efficacy endpoint, a statistically significant difference between the percent of patients with a negative provocation test compared to placebo at Week 12 as assessed by the TempTest® in ColdU and the FricTest® in SD. Secondary and exploratory endpoints in the study were also achieved at Week 12 and strongly support the primary endpoint results, including responder analyses, improvements in Critical Temperature and Critical Friction Thresholds (CFT and CFT), changes in WI-NRSprovo (itch associated with provocation test) and Urticaria Control Test. Demographics and baseline disease characteristics were well balanced across treatment groups. Patients on study had poorly controlled disease on initial provocation testing. In cold urticaria, patients presented with a mean baseline critical temperature threshold of approximately 19°C or 66°F on the TempTest on initial provocation testing. In patients with symptomatic dermographism baseline FricTest thresholds were an average of 3.6 out of 4 pins. UCT scores at baseline also reflected poorly controlled disease.

Summary of Clinical Assessments at Week 12

​ Cold Urticaria ​ ​ ​ Symptomatic Dermographism

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Patients experienced rapid disease improvement as early as two weeks (the first assessment) after receiving the initial dose of barzolvolimab as demonstrated by reductions in critical temperature and friction thresholds resulting in hives and rapid reduction in itch at the time of provocation testing (WI-NRSprovo).

Barzolvolimab was well tolerated with a favorable safety profile consistent with prior studies. Most adverse events were grade 1 (mild). Through 12 weeks, the most common treatment emergent adverse events in barzolvolimab treated patients were hair color changes (13%; Grade 1, n=15 / Grade 2, n=2) and neutropenia (10%; Grade 1, n=7 / Grade 2, n=6), which are mechanism related (KIT) and expected to be reversible. The rate of infections was similar between barzolvolimab-treated patients and placebo with no association between neutropenia and infections.

In March 2025, quality of life data were presented at the AAAAI Annual Meeting 2025. A marked and rapid improvement in urticaria control (UCT) and quality of life (DLQI) was observed and sustained through the 12-week period in patients with ColdU and SD. Up to 60% of patients reported that CIndU symptoms no longer had an impact on their quality of life at Week 12 and up to 69% of patients reported well-controlled urticaria based on UCT at Week 12.

Patients on study continued to receive barzolvolimab for up to 20 weeks. Data from this longer term treatment period were presented in November 2025 at the ACAAI Annual Scientific Meeting. The data demonstrated sustained efficacy and a favorable safety profile over the 20 week placebo controlled treatment period. Key highlights at 20 weeks included:

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We believe these results strongly support the further development of barzolvolimab in CIndU. In December 2025, we initiated a Phase 3 study of barzolvolimab in adult patients with ColdU and SD who remain symptomatic despite H1 antihistamine treatment. The Phase 3 trial (EMBARQ-ColdU and SD) is a randomized, double-blind, placebo-controlled, parallel group, global Phase 3 study (approximately 75 clinical trial sites across 7 countries) where approximately 240 participants will be enrolled to 2 separate cohorts (differentiated by subtype) to include approximately 120 participants with ColdU and 120 participants with SD. Participants in each cohort will be randomized in a 1:1 ratio to one of two treatment arms: cohort 1: barzolvolimab 150 mg every 4 weeks (Q4W) following a loading dose of 450 mg on Day 1 or cohort 2: matching placebo for 24 weeks. The primary endpoint of the study will evaluate the percentage of patients with complete response (negative provocation test) at Week 12 as assessed by the TempTest® in ColdU and the FricTest® in SD. After completing the treatment period, participants will continue to be followed for 16 weeks.

Prurigo Nodularis (PN)

We have expanded clinical development of barzolvolimab into prurigo nodularis (PN). PN is a chronic skin disease characterized by the development of hard, intensely itchy (pruritic) nodules on the skin. Mast cells through their interactions with sensory neurons and other immune cells are believed to play an important role in amplifying chronic itch and neuroinflammation, both of which are a hallmark of PN. There is currently only one FDA approved therapy for PN, representing an area of significant unmet need. Industry sources estimate there are approximately 154,000 patients in the United States with PN who have undergone treatment within the last 12 months and, of these, approximately 75,000 would be biologic-eligible.

We have completed a Phase 1b multi-center, randomized, double-blind, placebo-controlled intravenous study in PN. Data from the study, including 24 weeks of follow-up, were presented at the 12th World Congress on Itch (WCI) held in November 2023. 24 adults (evaluable: n=23 safety; n=22 efficacy) with moderate to severe PN were randomized across three arms: (1) barzolvolimab 3.0 mg/kg (n=9), barzolvolimab 1.5 mg/kg (n=7) and placebo (n=8). The primary endpoint of the study was safety; key secondary endpoints include changes from baseline in Worst Itch-Numerical Rating Scale (WI-NRS) & Investigator Global Assessment (IGA). The primary timepoint for evaluation of clinical activity was 8 weeks; patients were followed for safety and efficacy endpoints to 24 weeks. Patients on study generally had moderate to severe disease with mean baselines scores across all arms of 8.6 for WI-NRS and 3.3 for IGA.

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A single IV dose of 3.0 mg/kg barzolvolimab resulted in rapid and durable reductions in itch and healing of skin lesions in patients with moderate to severe PN and that barzolvolimab was generally well tolerated.

% of Subjects with ≥4-point decrease in WI-NRS

Dose Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8

​

% of Subjects with IGA 0/1

Dose Baseline Week 2 Week 4 Week 8

​

In April 2024, we initiated a Phase 2 subcutaneous study in PN. This randomized, double-blind, placebo-controlled, parallel group study is evaluating the efficacy and safety profile of 2 dose levels of barzolvolimab compared to placebo in approximately 120 patients with moderate to severe PN who had inadequate response to prescription topical medications, or for whom topical medications are medically inadvisable (such as concerns for safety). Patients are randomly assigned on a 1:1:1 ratio to receive barzolvolimab injections of 150 mg Q4W after an initial loading dose of 450 mg, 300 mg Q4W after an initial loading dose of 450 mg, or placebo during a 24‐week Treatment Phase. Participants then enter a follow-up phase with no study treatment for an additional 16 weeks through Week 40. The primary objective of this study is to evaluate the clinical effect of barzolvolimab, compared to placebo, on itch response as measured by the proportion of participants with ≥ 4-point improvement in the worst intensity itch per a numeric rating scale (WI-NRS). Secondary objectives include but are not limited to additional measures of itch response from baseline compared to different timepoints, the assessment of skin lesions as measured by the Investigator Global Assessment (IGA), QoL outcomes and safety. The study includes approximately 75 clinical trial centers worldwide, including the United States. Enrollment was completed in December 2025. Topline data from the study is expected in summer 2026.

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Atopic Dermatitis (AD)

In December of 2024, we announced the initiation of a Phase 2 study in atopic dermatitis (AD). AD is one of the most common chronic inflammatory skin diseases, with a lifetime prevalence of up to 20% of the US population and a substantial impact on quality of life (Kawakami, et al. 2009). Mast cells are strongly implicated in all facets of AD pathophysiology and the fundamental processes that characterize AD, including epithelial barrier dysfunction, immune cell recruitment, neuroinflammation (Keith, et al. 2023) and multiple other mast cell-associated factors that correlate with disease severity. Activated mast cells are also found in increased numbers in lesional biopsies. Two-thirds of patients treated with first line systemic therapy (1.7 million patients in the US) do not achieve complete control of their atopic dermatitis (Simpson, Bieber, Guttman-Yassky, et al. 2016) and new therapies that offer rapid, meaningful relief from the severe itching and breakdown of the skin associated with AD are needed. Given barzolvolimab’s potential as a mast cell depleting agent, we believe AD is an important indication for future study.

The randomized, double-blind, placebo-controlled, parallel group Phase 2 study is evaluating the efficacy and safety profile of subcutaneous barzolvolimab in patients with moderate to severe AD. Approximately 120 patients will be randomly assigned on a 1:1:1 ratio to receive subcutaneous injections of barzolvolimab at either 150 or 300 mg or placebo every 4 weeks after an initial loading dose of 450 mg or placebo during a 16-week placebo-controlled treatment phase. Participants randomized into the placebo arm will be re-randomized at Week 16 into 1 of the 2 active treatment arms. Patients then enter a 16-week active treatment phase, in which all patients will receive barzolvolimab every 4 weeks. The primary endpoint of the study is to evaluate the clinical efficacy of the two dose levels compared to placebo using the Peak Pruritus Numerical Rating Scale (PP-NRS) at Week 16, a well‐defined, reliable, sensitive and valid scale for evaluating worst itch intensity in adults with moderate‐to‐severe AD. Secondary endpoints include the evaluation of the clinical efficacy of barzolvolimab, compared to placebo across multiple patient-reported outcomes, including assessing impressions of disease change and severity and improvements in quality of life. When all clinical trial sites are open, the study includes approximately 40 clinical trial centers in the United States. Enrollment was completed in January 2026. Topline data from the study is expected in late 2026.

Eosinophilic Esophagitis (EoE)

In August 2025, we announced the discontinuation of development in eosinophilic esophagitis (EoE), a chronic inflammatory disease of the esophagus, based on interim results from a Phase 2 study. Identifying the key drivers of EoE has challenged the field and research has suggested that mast cells could play an important role in the disease pathogenesis. We designed this study to determine if barzolvolimab could deplete mucosal (intraepithelial) mast cells and, in turn, improve clinical outcomes in EoE. The primary endpoint of the study, absolute change from baseline to Week 12 in peak esophageal intraepithelial mast cell count was met, but the profound mast cell depletion observed did not result in improvement in EoE symptoms or endoscopic assessment of disease activity compared to placebo. Consistent with previously reported studies, barzolvolimab demonstrated a favorable safety and tolerability profile. Based on these results, further development in EoE was discontinued. The results do support future development with KIT- or SCF-targeted therapies in other GI indications where mucosal mast cells are believed to play an important role.

Additional Barzolvolimab Development Activities

The barzolvolimab manufacturing process has been successfully transferred and scaled up to produce larger cGMP batches at both Drug Substance (DS) and Drug Product (DP) commercial Contract Development and Manufacturing Organizations in support of late-stage trials and to prepare for potential commercialization. Drug product manufacturing into 1 mL pre-filled syringes has been completed and pre-filled syringes are actively being used in Phase 3 trials. In 2025, we initiated the Process Performance Qualification (PPQ) manufacturing runs for DS and anticipate the completion of those activities in 2026. We are currently preparing for the DP PPQ activities and expect to complete these activities in 2026.

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. The final histologic analysis and study report were completed in early 2023 and were consistent with previously reported results. We are encouraged with these findings and believe these data strongly support continued development of barzolvolimab.

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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. 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.

CDX-622

CDX-622 is a bispecific antibody that targets two complementary pathways that drive chronic inflammation, potently neutralizing the alarmin thymic stromal lymphopoietin (TSLP) and depleting mast cells via stem cell factor (SCF) starvation. TSLP has been directly implicated in several respiratory and dermatological disorders, such as asthma, chronic obstructive pulmonary disease (COPD), eosinophilic esophagitis, atopic dermatitis and chronic spontaneous urticaria, and in fibrotic diseases such as systemic sclerosis and idiopathic pulmonary fibrosis. In these disorders, TSLP is often upregulated and associated with disease severity. Similarly, mast cells drive or contribute to the pathophysiology of allergic, inflammatory, autoimmune and fibrotic disorders and CDX-622 contains a unique SCF neutralizing function that is expected to inhibit and deplete mast cells. Combined neutralization of SCF and TSLP with CDX-622 is expected to simultaneously reduce tissue mast cells and inhibit Type 2 inflammatory responses to potentially offer enhanced therapeutic benefit in inflammatory and fibrotic disorders. CDX-622 has been engineered to disable effector function (AQQ) and reduce clearance (YTE). In preclinical studies, CDX-622 inhibits TSLP and SCF with similar potency to both its respective parental mAbs and comparator mAbs in vitro and preferentially inhibits the soluble over the membrane form of SCF, which may lead to differential impact on KIT-dependent processes. CDX-622 was well tolerated in a multi-dose 8 week toxicology study in non-human primates and led to a profound mast cell depletion in several tissues. The No Adverse Event Level (NOAEL) was established to be 75 mg/kg, the highest dose level tested.

In November 2024, we initiated a Phase 1 study of CDX-622 in healthy volunteers and enrollment was completed in January 2026. The Phase 1a clinical trial is a three-part, randomized, double-blind, placebo-controlled, dose escalation study designed to assess the safety, pharmacokinetics, and pharmacodynamics of CDX-622 in up to 80 healthy participants. A single dose of CDX-622 or placebo was administered intravenously (IV) once during Part 1. In Part 2, CDX-622 or placebo was administered IV every 2 weeks (Q2W) for up to 6 weeks following the first dose, for a total of 4 doses. In Part 3, a single dose of CDX-622 or placebo was administered subcutaneously once. Participants are followed for 12 weeks in all Parts following the last dose of study drug. The pharmacodynamic biomarkers from blood and skin will be highly informative on the ability of CDX-622 to engage and neutralize SCF and TSLP.

We presented positive data from the Phase 1 single ascending dose portion of the study (Part 1) at the CIA (Collegium Internationale Allergologicum) Biennial Symposium in October 2025. CDX-622 was well tolerated with no dose limiting toxicities and no emergent events related to systemic KIT inhibition. CDX-622 exhibited a good pharmacokinetic profile and induced rapid and sustained dose dependent reductions in serum tryptase, indicative of mast cell inhibition and depletion. The multiple ascending doses portion of the study (Part 2) and subcutaneous administration (Part 3) are ongoing with data expected in the third quarter of 2026.

In January 2026, we initiated an open-label, single-dose Phase 1 proof of mechanism study to assess the safety, pharmacodynamics, and pharmacokinetics of CDX-622 in adults with mild to moderate asthma. Participants will receive a single IV infusion of CDX-622 and be followed for 12 weeks. PD effects of CDX-622 on fractional exhaled nitric oxide (FeNO), absolute eosinophil count (AEC) and serum biomarkers, including TSLP- and SCF-related biomarkers, will be evaluated.

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Partnerships

We may enter into co-development and commercialization partnerships for any of our programs where appropriate. In the past, we have entered into collaborative partnership agreements with pharmaceutical and other companies and organizations that provided financial and other resources, including capabilities in research, development, manufacturing, and sales and marketing, to support our research and development programs and may enter into more of them in the future.

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 is our significant research collaboration and license agreement for our current clinical drug candidates.

Yale University (Yale)

Under a license agreement with Yale, we may be required to make a one-time payment to Yale of $3.0 million with respect to barzolvolimab upon achievement of a specified commercial milestone. In addition, we may be required to pay a low single-digit royalty on annual worldwide net sales of barzolvolimab. Unless earlier terminated by us or Yale, the Yale license agreement is due to expire no later than May 2038 but may expire earlier on a country-by-country basis under specified circumstances.

Competition

The biotechnology and pharmaceutical industry is intensely competitive and subject to rapid and significant technological change. Many of the products that we are attempting to develop and commercialize will be competing with existing therapies. Other companies are pursuing the development of new therapies that target the same diseases and conditions that we are targeting and may compete directly with our drug candidates. We face competition from companies, major universities and research institutions in the United States and abroad, including a number of large pharmaceutical companies, as well as firms specialized in the development and production of targeted therapies and immune modulators. Some of our competitors possess substantially greater financial, technical and human resources than we do.

​

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The following table is a summary of 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 barzolvolimab for treatment of CSU, CIndU, PN, and AD.

​ ​

Competitor ​ ​ ​ Competitor Product ​ ​ ​ Indication(s)

Abbvie ​ Rinvoq ​ AD

Akeso Bio ​ AKT120 ​ AD

Amgen/Kiowa Kirin ​ Rocatinlimab ​ AD and PN

Celltrion ​ CT-P39, omalizumab biosimilar ​ CSU

Eli Lilly ​ Olumiant and Ebglyss ​ AD

Galderma/Chugai ​ Nemluvio ​ PN and AD

Genentech/Novartis ​ Xolair ​ CSU

Incyte ​ Povorcitinib ​ PN

Kashiv Biosciences ​ ADL-018 omalizumab biosimilar ​ CSU

Leo Pharma ​ Adbry ​ AD

Medimetriks ​ Difamilast ​ AD

Novartis ​ Remibrutinib ​ CSU and CIndU

Pfizer ​ Cibinqo ​ AD

Regeneron/Sanofi ​ Dupixent ​ CSU, PN, and AD

Sanofi ​ Amlitelimab ​ AD

Teva ​ Tev-45779, omalizumab biosimilar ​ CSU

Vanda Pharmaceuticals ​ Tradipitant ​ AD

​

Our competitors may utilize discovery technologies and techniques or partner with collaborators in order to develop products more rapidly or successfully than us or our collaborators are able to. In addition, some competitors have significantly greater experience than we have in conducting preclinical and nonclinical testing and human clinical trials of drug candidates, scaling up manufacturing operations and obtaining regulatory approvals of drugs and manufacturing facilities. Accordingly, our competitors may succeed in obtaining regulatory approval for drugs more rapidly than we do. If we obtain regulatory approval and commence commercial sales of our drug candidates, we also will compete with respect to manufacturing efficiency and sales and marketing capabilities, areas in which we currently have limited experience.

In addition, academic institutions, government agencies and other public and private organizations conducting research may seek patent protection with respect to potentially competitive products or technologies and may establish exclusive collaborative or licensing relationships with our competitors. Moreover, technology controlled by third parties that may be advantageous to our business may be acquired or licensed by our competitors, thereby preventing us from obtaining technology on commercially reasonable terms, if at all. We will also compete for the services of third parties that may have already developed or acquired internal 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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Manufacturing

We are a research and development company and have limited experience in commercial manufacturing. To conduct late-stage clinical trials, as well as manufacture and commercialize our drug candidates, we engage CDMOs in the U.S and outside the U.S. to manufacture our drug candidates on a large scale at a competitive cost and in accordance with current Good Manufacturing Practices (cGMP) and U.S. and foreign regulatory requirements, as applicable. We also rely on CDMOs for filling, labeling and storage for studies inside and outside the U.S. Any manufacturing failures or compliance issues at our CDMOs could cause delays in our clinical studies or commercialization of our drug candidates.

We currently 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 drug candidates to clinical sites in the U.S., EU and ROW for early-stage clinical trials. We have manufactured barzolvolimab and CDX-622 drug substance in our Fall River facility for our current and planned Phase 1 and Phase 2 clinical trials.

Our barzolvolimab drug product is currently administered subcutaneously. The subcutaneous formulation allows for potential self-administration at home, eliminating the need for intravenous dosing in a hospital or clinic setting. The barzolvolimab manufacturing process has been successfully transferred and scaled up to produce larger cGMP batches at both Drug Substance (DS) and Drug Product (DP) commercial Contract Development and Manufacturing Organizations in support of late-stage trials and to prepare for potential commercialization. Drug product manufacturing into 1 mL pre-filled syringes has been completed and pre-filled syringes are actively being used in Phase 3 trials. In 2025, we initiated the Process Performance Qualification (PPQ) manufacturing runs for DS and anticipate the completion of those activities in 2026. We are currently preparing for the DP PPQ activities and expect to complete these activities in 2026.

Commercial Organization

We have limited commercial resourcing and 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. On November 10, 2025, we announced the appointment of a new Chief Commercial Officer. 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.

Patents, Licenses and Proprietary Rights

In general, our intellectual property strategy is to protect our technology by filing patent applications and obtaining patent rights covering our own technology, both in the United States and in foreign countries that we consider important to our business. In addition, we have acquired and will seek to acquire as needed or desired, exclusive rights of others through assignment or license to complement our portfolio of patent rights. We also rely on trade secrets, unpatented know-how and technological expertise and innovation to develop and maintain our competitive position.

Patents

The successful development and marketing of products by us will depend in part on our ability to create and maintain intellectual property, including patent rights. We are the owner or exclusive licensee to proprietary patent positions in the areas of immunotherapy technologies and antibody technologies. Although we continue to pursue patent protection for our products, no assurance can be given that any pending application will issue as a patent, that any issued patent will have a scope that will be of commercial benefit or that we will be able to successfully enforce our patent position against infringers. We routinely review our patent portfolio and adjust our strategies for prosecution and maintenance of individual cases according to a number of factors, including program priorities, stage of development and patent term.

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The key patents and patent applications owned by us or licensed to us that we consider important to our current clinical programs include the following (except where stated otherwise, the indicated and estimated patent expiry dates are the estimated normal expirations if all maintenance fees and annuities are paid when due, and do not include any possible additional terms for Patent Term Adjustments (PTAs), Patent Term Extensions (PTEs), other term extensions or Supplementary Protection Certificates (SPCs), if these may be secured in due course):

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 licenses from third parties are necessary but cannot be obtained, commercialization of the covered products might be delayed or prevented. Even if these licenses can be obtained, they would probably require us to pay ongoing royalties and other costs, which could be substantial.

Although a patent has a statutory presumption of validity in the United States, the issuance of a patent is not conclusive as to validity or as to the enforceable scope of the patent claims. The validity or enforceability of a patent after its issuance by the Patent and Trademark Office can be challenged in litigation. As a business that uses a substantial amount of intellectual property, we face a heightened risk of intellectual property litigation. If the outcome of the litigation is adverse to the owner of the patent, third parties may then be able to use the invention covered by the patent without authorization or payment. There can be no assurance that our issued patents or any patents subsequently issued to or licensed by us will not be successfully challenged in the future. In addition, there can be no assurance that our patents will not be infringed or that the coverage of our patents will not be successfully avoided by competitors through design innovation.

We are aware that others, including universities and companies, have filed patent applications and have been granted patents in the United States and other countries which claim subject matter potentially useful or necessary to the commercialization of our products. The ultimate scope and validity of existing or future patents which have been or may be granted to third parties, and the availability and cost of acquiring rights in those patents necessary to the manufacture, use or sale of our products presently cannot be determined by us.

Third parties may have or may obtain valid and enforceable patents or proprietary rights that could block us from developing products using our technology, including:

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In addition to the patents referred to in the previous paragraphs, there may be other patent applications and issued patents belonging to competitors that may require us to alter our drug candidates and immunotherapeutic delivery systems, pay licensing fees or cease some of our activities. If our drug candidates conflict with patents that have been or may be granted to competitors, universities or others, the patent owners could bring legal action against us claiming damages and seeking to enjoin manufacturing and marketing of the patented products. If any of these actions is successful, in addition to any potential liability for damages, we could be required to obtain a license in order to continue to manufacture or market the affected products. There can be no assurance that we would prevail in any such action or that any license required under any such third-party patent would be made available on acceptable terms or at all. We believe that there may be significant litigation in the biotechnology industry regarding patent and other intellectual property rights. If we become involved in that litigation, we could consume substantial resources.

Licenses

We have entered into significant license agreements relating to technologies that are being developed by us. Typically, institutions have granted us an exclusive worldwide license (with right to sublicense) to make, use and sell products embodying the licensed technology, subject to the reservation by the licensor of a non-exclusive right to use the technologies for non-commercial research purposes. Generally, the term of each license is through the expiration of the last of the patents issued with respect to the technologies covered by the license and/or a specified period from first commercial sale on a territory-by- territory basis. We have generally agreed to use reasonable efforts to develop and commercialize licensed products and to achieve specified milestones and pay license fees, milestone payments and royalties based on the net sales of the licensed products or to pay a percentage of sublicense income. If we breach our obligations, the licensor has the right to terminate the license, and, in some cases, convert the license to a non-exclusive license. Generally, we control and are responsible for the cost of defending the patent rights of the technologies that we license.

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.

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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:

● satisfactory completion of an FDA advisory committee review, if applicable;

● FDA review and approval of the NDA or BLA.

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. Studies that are conducted in multiple countries are reviewed and authorized by additional regional or country specific health authorities in addition to the FDA. The

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additional international review often is slower than that of the FDA and may result in regulatory opinions that are different than the decisions provided by the FDA.

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.

Disclosure of Clinical Trial Information

Sponsors of clinical trials of FDA-regulated products, including biological products, are required to register and disclose certain clinical trial information on the website www.clinicaltrials.gov. Information related to the product, patient population, phase of investigation, trial sites and investigators, and other aspects of a clinical trial are then made public as part of the registration. Sponsors are also obligated to disclose the results of their clinical trials after completion. Disclosure of the results of clinical trials can be delayed in certain circumstances for up to two years after the date of completion of the trial. Competitors may use this publicly available information to gain knowledge regarding the progress of clinical development programs as well as clinical trial design.

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 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

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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 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 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

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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.

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.

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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:

● fines, untitled and warning letters or holds on post-approval clinical trials;

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 and Exclusivity

The Biologics Price Competition and Innovation Act of 2009 (“BPCIA”) created an abbreviated approval pathway for biological products shown to be highly similar to, or interchangeable with, an FDA-licensed reference biological product. The FDA has issued several guidance documents outlining an approach to review and approval of biosimilars.

Biosimilarity, which requires that there be no clinically meaningful differences between the biological product and the reference product in terms of safety, purity, and potency, can be shown through analytical studies, animal studies, and a clinical study or studies. Interchangeability requires that a product is biosimilar to the reference product and the product must demonstrate that it can be expected to produce the same clinical results as the reference product in any given patient and, for products that are administered multiple times to an individual, the biologic and the reference biologic may be alternated or switched after one has been previously administered without increasing safety risks or risks of diminished efficacy relative to exclusive use of the reference biologic.

The BPCIA includes, among other provisions, a 12-year exclusivity period from the date of first licensure, or BLA approval, of the reference product, during which approval of a 351(k) application referencing that product may not be made effective; a four-year exclusivity period from the date of first licensure of the reference product, during which a 351(k) application referencing that product may not be submitted; and an exclusivity period for certain biological products that have been approved through the 351(k) pathway as interchangeable biosimilars.

The BPCIA also establishes procedures for identifying and resolving patent disputes involving applications submitted under section 351(k) of the PHSA.

The BPCIA is complex and its interpretation and implementation by the FDA remains unpredictable. In addition, government proposals have sought to reduce the 12-year reference product exclusivity period. Other aspects of the BPCIA, some of which may impact the BPCIA exclusivity provisions, have also been the subject of recent litigation. As a result, the ultimate effect, implementation, and meaning of the BPCIA is subject to uncertainty.

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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.

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 all 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.

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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 acquisition 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 significant 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 value over and above the currently available treatment options. Our drug candidates may not be considered medically necessary, provide insufficient incremental value, or may not be deemed cost-effective per payor criteria. 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. Given that the Inflation Reduction Act is now in place, potential implications for the biopharma industry are still being assessed. In the meantime, third-party payors are increasingly challenging the prices charged for medical products and services and examining the medical necessity and cost-effectiveness of medical products and services, in addition to their safety and efficacy. If these third-party payors do not consider our drugs to be cost-effective compared to other available therapies, they may not cover our drugs after approval as a benefit under their plans or, if they do, the level of reimbursement and/or restrictions in formulary placement may be such that they would significantly limit projected sales volumes. In addition to third-party payors, we will also need to negotiate formulary placement with hospitals, health systems and certain independent delivery networks. Such negotiations may be more protracted than anticipated and may be compromised because of similar considerations, relating to insufficient incremental value and/or cost-effectiveness.

Pricing and reimbursement schemes vary widely from country to country. For example, certain EU member states may approve a specific price and volume for a drug product after which incremental revenues or profits need to be paid back by way of rebates. They may also institutionalize utilization restrictions, curb physicians’ drug budgets, provide conditional reimbursement schemes that require additional evidence to be generated post-marketing authorization, etc. The downward pressure on health care costs in general, including prescription drugs, has been evident in EU markets for some time and is now a major focus of federal and state governments in the U.S. As a result, increasingly high barriers are being erected to the pricing and reimbursement of new drugs, despite regulatory efforts to bring drugs to market sooner. Cross- border trade has existed for some time in the EU, allowing pharmacies in one country to import, at a lower price, drug from another country, further exerting pricing pressures across the EU. There is U.S. legislation that establishes a process for states to import less expensive drugs from Canada to the U.S. In January 2024, the FDA authorized the state of Florida to establish such a program, although Florida must take several other steps before drugs begin to be imported. There can be no assurance that any country that has price controls or reimbursement limitations for drug products will allow favorable reimbursement and pricing arrangements for any of our drugs.

The marketability of any drugs for which we receive regulatory approval for commercial sale may suffer if third-party payors and/or hospital administrators fail to provide adequate coverage, reimbursement or formulary placement. Coverage policies, third-party reimbursement rates and drug pricing regulations may change in the future. In addition, the States may continue to consider legislation of their own (e.g. Prescription Drug Afforability Boards) which could further restrict the ability to freely price drugs and/or curb utilization in the U.S. Even if favorable coverage and reimbursement status is attained for one or more drugs for which we receive regulatory approval, less favorable coverage policies and reimbursement rates may be implemented in the future.

Employees

As a mission driven organization, we believe the engagement and dedication of our employees is central to our success and employ talented individuals who have the skills and expertise to help us achieve our goals.

As of December 31, 2025, we had 198 full-time employees, 30 of whom have Ph.D. and/or M.D. degrees. Of these employees, 166 were engaged in or directly support research and development activities. We consider our relationship with our employees to be good.

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We believe that our success depends in large part on our ability to attract and retain experienced and skilled employees. We endeavor to provide competitive compensation and benefits packages designed to attract, retain and reward talented individuals who possess the skills necessary to support our business objectives, assist in the achievement of our strategic goals and increase stockholder value. We employ a pay for performance philosophy. Annual salary increases, incentive bonuses and stock option grants are available to all employees and are based on merit and include individual and corporate performance factors.

Much of our success is rooted in the diversity of our teams and our commitment to inclusion. We value diversity at all levels and continue to focus on extending our diversity and inclusion initiatives across our entire workforce. We believe that our business benefits from the different perspectives that a diverse workforce brings.

We are committed to the health, safety and well-being of our employees at all times. We follow federal, state and local rules and guidelines to ensure the safety of our workforce and provide resources to assist our employees in managing their overall physical and mental health.

Research and Development

We have dedicated a significant portion of our resources to our efforts to develop our drug candidates. We incurred research and development expenses of $245.1 million, $163.6 million and $118.0 million during the years ended December 31, 2025, 2024 and 2023, respectively. We anticipate that a significant portion of our operating expenses will continue to be related to research and development in 2026 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 Business Conduct and 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.

Item 1A. RISK FACTORS

You should consider carefully these risk factors together with all of the information included or incorporated by reference in this Annual Report in addition to our financial statements and the notes to our financial statements. This section includes forward-looking statements.

The following is a discussion of the risk factors that we believe are material to us at this time. These risks and uncertainties are not the only ones facing us, and there may be additional matters that we are unaware of or that we currently consider immaterial. All of these could adversely affect our business, results of operations, financial condition and cash flows.

Summary of Risk Factors

Risks Related to Our Financial Condition and Capital Requirements

● Risks related to our need for additional capital to fund our operations.

Risks Related to Development and Regulatory Approval of Drug Candidates

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Risks Related to Commercialization of Our Drug Candidates

● Risks related to reimbursement decisions by third-party payors.

Risks Related to Reliance on Third Parties

● Risks related to our reliance on third parties.

Risks Related to Business Operations

● Risks related to strategic transactions.

● Risks related to managing our growth.

● Risks related to hazardous materials.

● Risks related to product liability claims.

Risks Related to Intellectual Property

● Risks related to intellectual property.

Regulatory Risks

● Risks related to the regulatory approval process for our drugs.

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● Risks related to changes in product candidate manufacturing or formulation.

● Risks related to our compliance with laws and regulations.

Risks Related to Our Capital Stock

● Risks related to the volatility of our common stock.

● Risks related to our use of our net operating loss carryforwards.

General Risk Factors

● Risks related to internal controls over financial reporting.

● Risks that our competitors may develop technologies that make ours obsolete.

● Risks related to health epidemics and outbreaks.

● Risks related to the global economy and supply chain disruptions.

● Risks related to the loss of our key executives and scientists.

● Risks related to our compliance with the Nasdaq Listing Rules.

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 $1.8 billion as of December 31, 2025. 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.

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

We have incurred operating losses of $287.4 million, $195.1 million and $154.5 million during 2025, 2024, and 2023, respectively, and expect to incur an operating loss in 2026 and beyond. We believe that operating losses will continue in 2026 and beyond because we are planning to incur significant costs associated with the development of our drug candidates and, if we are successful in obtaining regulatory approval to market one or more of our product candidates, the marketing and commercialization of such approved product(s). During the years ended December 31, 2025, 2024 and 2023, we incurred $111.8 million, $73.0 million and $32.4 million in clinical trial expense and $47.1 million, $16.4 million and $24.1 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.

Even if we are successful in obtaining regulatory approval for barzolvolimab or one or more of our other drug candidates, our ability to generate revenue will still be dependent on a number of factors outside of our control, including, the size of the addressable market, the label for which approval is granted, the accepted price for the product, and/or the ability to get and maintain adequate coverage and reimbursement. See “If our drug candidates for which we obtain regulatory approval do not achieve broad acceptance from physicians, patients and third-party payors, we may be unable to generate significant revenues, if any” below.

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, 2025, we had cash, cash equivalents and marketable securities of $518.6 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:

● licensing of drug candidates with existing or new collaborative partners;

● possible business combinations;

● issuance of debt; or

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 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.

In 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

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Kolltan merger, in the event that regulatory approval by the United States Food and Drug Administration or European Medicines Agency of certain drug candidates are achieved, we will be required to pay to the former stockholders of Kolltan a milestone payment of $52,500,000, which milestone payment 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.

We may require additional capital to fund the milestone payment in cash, depending on the facts and circumstances at the time such payment becomes 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 milestone payment in shares of our common stock, our stockholders would experience substantial dilution.

Risks Related to Development and Regulatory Approval of Drug Candidates

Our long-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 decide, or regulators may require us, to conduct additional clinical or preclinical trials. In addition, data obtained from trials are susceptible to varying interpretations, and regulators may not interpret our data as favorably as we do, which may delay, limit or prevent regulatory approval. Success in preclinical testing and early clinical trials does not ensure that later clinical trials will generate the same results or otherwise provide adequate data to demonstrate the efficacy and safety of a drug candidate. As part of development, we also must show that we can formulate and manufacture our product candidates in compliance with regulatory requirements.

We will need substantial additional financing to complete the development of our drug candidates and comply with the regulatory requirements governing this process. Further, even if we complete the development of our drug candidates and gain marketing approvals from the FDA and comparable foreign regulatory authorities in a timely manner, we cannot be sure that such drug candidates will be commercially successful in the pharmaceutical market. If the results of clinical trials, the anticipated or actual timing of marketing approvals, or the market acceptance of any of our drug candidates, if approved, do not meet the expectations of investors or public market analysts, the market price of our common stock would likely decline.

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.

Premarket review of our product candidates by the FDA and/or other regulatory authorities is a lengthy and uncertain process and approval may be delayed, limited or denied, any of which would adversely affect our ability to generate operating revenues.

We are not permitted to market our drug product candidates in the United States until we receive approval of an application by the FDA. The time required to obtain approval by the FDA is unpredictable, but typically takes multiple years following the commencement of clinical trials, and depends upon numerous factors, including the substantial discretion of the FDA and the type, complexity and novelty of the product candidates involved. Similar processes are used in countries outside of the U.S. We have not submitted a marketing application such as BLA or NDA to the FDA or any similar application to any other regulatory authority in any jurisdiction.

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The FDA has substantial discretion in the drug approval process, including the ability to delay, limit or deny approval of a product candidate for many reasons. For example, the FDA:

● may change its approval policies or adopt new regulations; or

The time and expense of the approval process, as well as the unpredictability of future clinical trial results and other contributing factors, may result in our failure to obtain regulatory approval to market, in the United States or other jurisdictions, barzolvolimab and other drug candidates that we are developing or may seek to develop in the future, which would significantly harm our business, results of operations and prospects. In such case, we may also not have the resources to conduct new clinical trials and/or we may determine that further clinical development of any such drug candidate is not justified and may discontinue any such programs.

Disruptions at the U.S. FDA and other government agencies caused by funding shortages or otherwise could hinder their ability to hire and retain key leadership and other personnel, or otherwise review and process regulatory submissions in a timely manner, which could negatively impact our business.

The ability of the U.S. FDA to review and process regulatory submissions can be affected by a variety of factors, including government budget and funding levels, ability to hire and retain key personnel and accept the payment of user fees, and statutory, regulatory, policy changes, and other events that may otherwise affect the U.S. FDA’s ability to perform routine functions. For example, over the last several years, the U.S. government has shut down several times, including the most recent U.S. government shutdown which lasted from October 1, 2025 through November 12, 2025, and certain regulatory agencies, such as the U.S. FDA, have had to furlough U.S. FDA employees and suspend certain activities.

Disruptions at the U.S. FDA and other agencies may also slow the time necessary for new drugs to be reviewed and/or approved by necessary government agencies, which would adversely affect our business. If a prolonged government shutdown occurs or continues, or if the U.S. FDA or other regulatory authorities is prevented from conducting their regular inspections, reviews, or other regulatory activities, for any reason, it could significantly impact the ability of the U.S. FDA or other regulatory authorities to timely review and process our regulatory submissions, which could have a material adverse effect on our business.

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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 failed to obtain marketing approval. Drug candidates in later-stage clinical trials may fail to show the desired safety and efficacy despite having progressed through preclinical and initial clinical trials, even if certain analyses of primary or secondary endpoints in those early trials showed trends towards efficacy. Later-stage clinical trials with larger numbers of patients or longer durations of therapy may also reveal safety concerns that were not identified in earlier smaller or shorter trials. Our failure to demonstrate efficacy and safety data sufficient to support marketing approval for any of our other drug candidates would substantially harm our business, prospectus, financial condition and results of operations.

Product testing is critical to the success of our drug candidates but subject to delay or cancellation if we have difficulty enrolling patients.

As our portfolio of drug candidates moves from preclinical testing to clinical testing, and then through progressively larger and more complex clinical trials, we will need to enroll an increasing number of patients with the appropriate characteristics. At times we 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:

● the nature of the clinical test;

● the size of the patient population;

● the distance between patients and clinical test sites; and

● the eligibility criteria for the trial.

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

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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:

● difficulty in enrolling patients in our clinical trials;

● failure by regulators to authorize us to commence a clinical trial;

● drug candidates demonstrating a lack of efficacy during clinical trials;

● delays in completing data collection and analysis for clinical trials.

Any delay or failure to commence, enroll or complete clinical trials, fulfill regulatory requirements and obtain FDA approval for our drug candidates could have a material adverse effect on our cost to develop and commercialize, and our ability to generate revenue from, a particular drug candidate.

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 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.

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Our drug candidates, including barzolvolimab, are monoclonal antibodies, which are biologics. Side effects from biologics may include but are not limited to 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 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 team to be recruited quickly, we could be 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.

Failure to successfully validate, develop and obtain regulatory approval for companion diagnostics for our drug candidates, if needed, could harm our drug development strategy and operational results.

As an element of our clinical development approach, we may seek to screen and identify subsets of patients that express a certain biomarker or that have a certain genetic alteration who may derive meaningful benefit from our development drug candidates. To achieve this, one or more of our drug development programs may be dependent on the development and commercialization of a companion diagnostic by us or by third-party collaborators. Companion diagnostics are developed in conjunction with clinical programs for the associated drug candidate. Companion diagnostics are subject to regulation as medical devices and must themselves be approved for marketing by the FDA or certain other foreign regulatory agencies before the related drug candidate may be commercialized. The approval of a companion diagnostic as part of the product label will limit the use of the drug candidate to only

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those patients who express the specific biomarker it was developed to detect. We or our third-party collaborators may also experience delays in developing a sustainable, reproducible and scalable manufacturing process or transferring that process to commercial partners or negotiating insurance reimbursement for such companion diagnostic, all of which may prevent us from completing our clinical trials or commercializing our drugs on a timely or profitable basis, if at all.

We and our third-party collaborators may encounter difficulties in developing and obtaining approval for these companion diagnostics. Any delay or failure by us or third-party collaborators to develop or obtain regulatory approval of a companion diagnostic could delay or prevent approval of our related drug candidates or, if regulatory approval is obtained, delay or limit our ability to commercialize our related drug candidates.

Any delay in obtaining regulatory approval would have an adverse impact on our ability to earn future revenues.

It is possible that none of the drug candidates that we develop will obtain the regulatory approvals necessary for us to begin commercializing them. The time required to obtain FDA and other approvals is unpredictable but in general takes years following the commencement of clinical trials, depending upon the nature of the drug candidate. Any analysis we perform of data from clinical activities is subject to confirmation and interpretation by regulatory authorities, which could delay, limit or prevent regulatory approval. Any delay or failure in obtaining required approvals could have a material adverse effect on our ability to generate revenues from the particular drug candidate including, but not limited to, loss of patent term during the approval period. Furthermore, if we, or our partners, do not reach the market with our products before our competitors offer products for the same or similar uses, or if we, or our partners, are not effective in marketing our products, our revenues from product sales, if any, will be reduced.

We face intense competition in our development activities. We face competition from many companies in the United States and abroad, including a number of large pharmaceutical companies. Most of our competitors have substantially greater resources, more extensive experience in conducting preclinical studies and clinical testing and obtaining regulatory approvals for their products, greater operating experience, greater research and development and marketing capabilities and greater production capabilities than those of ours. These companies might succeed in obtaining regulatory approval for competitive products more rapidly than we can for our products, especially if we experience any delay in obtaining required regulatory approvals.

We may enter into collaboration agreements for the licensing, development and ultimate commercialization of some of our drug candidates including, where appropriate, for our lead drug candidates. In such cases, we will depend greatly on our third-party collaborators to license, develop and commercialize such drug candidates, and they may not meet our expectations.

We may enter into co-development and commercialization partnerships for our drug candidates where appropriate. The process of identifying collaborators and negotiating collaboration agreements for the licensing, development and ultimate commercialization of some of our drug candidates may cause delays and increased costs. We may not be able to enter into collaboration agreements on terms favorable to us or at all. Furthermore, some of those agreements may give substantial responsibility over our drug candidates to the collaborator. Some collaborators may be unable or unwilling to devote sufficient resources to develop our drug candidates as their agreements require. They often face business risks similar to ours, and this could interfere with their efforts. Also, collaborators may 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.

If we enter into collaboration agreements for one or more of our lead drug candidates, the success of such drug candidates will depend in great part upon our and our collaborators’ success in promoting them as superior to other treatment alternatives. We believe that our drug candidates can be proven to offer disease treatment with notable advantages over drugs in terms of patient compliance and effectiveness. However, there can be no assurance that we will be able to prove these advantages or that the advantages will be sufficient to support the successful commercialization of our drug candidates.

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Risks Related to Commercialization of Our Drug Candidates

We may face delays, difficulties or unanticipated costs in establishing and maintaining sales, marketing, market access, patient services and distribution capabilities or seeking a partnership for the commercialization of our drug candidates, even if regulatory approval is obtained.

We may retain full economic rights to our drug candidates or seek favorable economic terms through advantageous commercial partnerships. As a result, we may have full responsibility for commercialization of one or more of our drug candidates if and when they are approved for sale. We currently lack sufficient sales, marketing, market access, patient services and distribution capabilities to carry out this strategy. If any of our drug candidates are approved by the FDA, we will need a drug sales force with technical expertise and commercial-scale manufacturing capabilities prior to the commercialization of any of our drug candidates. We will also need to invest in new enterprise risk management programs to assist us with complying with the increasingly complex laws and requirements pertaining to commercial companies, including those related to regulatory oversight, financial reporting, and internal controls. We may not succeed in developing these new capabilities, the cost of establishing such capabilities may exceed any product revenue, or our direct marketing and sales efforts may be unsuccessful.

We may find it necessary to enter into strategic partnerships, co-promotion or other licensing arrangements. To the extent we enter into such strategic partnerships, co- promotion or other licensing arrangements, our product revenues may be lower than if we directly marketed and sold such drugs, and some or all of the revenues we receive will depend upon the efforts of third parties, which may not be successful and may not be within our control. If we are unable to enter into such strategic partnerships, co-promotion or other licensing arrangements on acceptable terms or at all, we may not be able to successfully commercialize our existing and future drug candidates. If we are not successful in commercializing any drug candidates for which we obtain regulatory approval, either on our own or through collaborations with one or more third parties, our future product revenue will suffer, and we may never achieve profitability or become unable to continue the operation of our business.

If our drug candidates for which we obtain regulatory approval do not achieve broad acceptance from physicians, patients and third-party payors, we may be unable to generate significant revenues, if any.

Even if we obtain regulatory approval for our drug candidates, our approved drugs may not gain market acceptance among physicians and patients. We believe that effectively marketing our drug candidates, if any of them are approved, will require substantial efforts, both prior to commercial launch and after approval. Physicians may elect not to prescribe our drugs, and patients may elect not to request or take them, for a variety of reasons, including:

● limitations or warnings contained in a drug’s FDA-approved labeling;

● limitations in the approved indications for our drug candidates;

● demonstrated clinical safety and efficacy compared to other drugs;

● the prevalence and severity of adverse side effects;

● effectiveness of education, sales, marketing and distribution support;

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● convenience and ease of administration of our drug candidates;

If our future drugs, if any, fail to achieve market acceptance or we fail to secure and maintain adequate coverage and reimbursement for our future drugs, if any, 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 or under a Risk Evaluation and Mitigation Strategy (REMS) drug safety program. Additionally, after 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:

● warning letters;

● civil or criminal penalties and fines;

● injunctions;

● consent decrees;

● suspension or withdrawal of regulatory approval;

● suspension of any ongoing clinical studies;

● voluntary or mandatory product recalls and publicity requirements;

● refusal to accept or approve applications for marketing approval of new drugs;

● seizure or detention of drugs or import bans.

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

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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.

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:

● the timing of regulatory approval, if any, of competitive drugs;

● marketing exclusivity, if any, awarded by the FDA to our drugs;

● the increasing use and development of alternate therapies;

● the rate of market penetration by competing drugs; and

● the termination of, or change in, existing arrangements with our partners.

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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. Similar regulatory review and risk-benefit assessments may apply to other regulatory authorities and payer bodies in markets around the world.