Celldex Therapeutics, Inc.

Previous wording

During the past five years through December 31, 2024, we incurred an aggregate of $459.7 million in research and development expenses. The following table indicates the amount incurred for each of our significant research programs and for other identified research and development activities during the six months ended June 30, 2025 and 2024. The amounts disclosed in the following table reflect direct research and development costs and an allocation of indirect research and development costs to each program.

Current wording

During the past five years through December 31, 2024, we incurred an aggregate of $459.7 million in research and development expenses. The following table indicates the amount incurred for each of our significant research programs and for other identified research and development activities during the nine months ended September 30, 2025 and 2024. The amounts disclosed in the following table reflect direct research and development costs and an allocation of indirect research and development costs to each program.

Previous wording

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 July 2023, we announced that enrollment was complete in the ongoing Phase 2 CSU study. In November 2023, we reported that barzolvolimab achieved the primary efficacy endpoint in this study, 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. 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 chronic inducible urticaria (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. We plan to present data from this study in 2025. Patients with resumption of symptoms were eligible to enroll into an open label extension.

Current wording

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 July 2023, we announced that enrollment was complete in the ongoing Phase 2 CSU study. In November 2023, we reported that barzolvolimab achieved the primary efficacy endpoint in this study, 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 was recently completed and data from the OLE are expected to be presented in the first quarter of 2026.

Previous wording

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 eosinophilic esophagitis (EoE), 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.

Current wording

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), atopic dermatitis (AD) and eosinophilic esophagitis (EOE; further development discontinued). 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.

Previous wording

Topline data from this study were presented in November of 2023 and 12 week treatment results were presented at the American Academy of Allergy, Asthma & Immunology (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).

Current wording

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).

Previous wording

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 American Academy of Allergy, Asthma & Immunology (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:

Current wording

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:

Previous wording

In addition, Celldex plans to initiate a global Phase 3b long term extension (LTE) study for patients who complete 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.

Current wording

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.

Previous wording

Chronic Inducible Urticaria (CIndU) Summary of Phase 1 and Phase 2 Data Presented to Date; Additional Phase 2 follow up data to be presented in 2025

Current wording

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

Previous wording

CIndUs are forms of urticaria that have an attributable cause or trigger associated with them, typically resulting in hives or wheals. The prevalence of CIndU is estimated at 0.5% of the total population and is reported to overlap in up to 36% of CSU patients (Weller et al. 2010. Hautarzt. 61(8), Bartlett et al. 2018. DermNet.Org). There are currently no approved therapies for chronic inducible urticarias other than antihistamines and patients attempt to manage symptoms associated with their disease through avoidance of triggers. We are currently exploring cold-induced and dermographism (scratch-induced) urticarias in an ongoing Phase 2 study.

Current wording

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.

Previous wording

In July 2022, we announced that the first patient had been dosed in a Phase 2 study in patients with CIndU who remain symptomatic despite antihistamine therapy; in April 2024, we announced that enrollment was complete. The study is being conducted at approximately 85 sites across approximately 12 countries. The randomized, double-blind, placebo-controlled, parallel group Phase 2 study is evaluating the efficacy and safety profile of multiple dose regimens of barzolvolimab in patients with CIndU to determine the optimal dosing strategy. 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 enter a follow-up phase for an additional 24 weeks. In addition, the study includes the option for patients who have symptoms following the treatment phase, including patients who were on placebo, to enroll in an open label extension where all patients receive 300 mg of barzolvolimab every 8 weeks. The primary endpoint of the study is the percentage of patients with a negative provocation test at Week 12. Secondary endpoints include safety and other assessments of clinical activity including CTT (Critical Temperature Threshold), CFT (Critical Friction Threshold) and WI-NRS (Worst itch numeric rating scale).

Current wording

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).

Previous wording

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. 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 reflect poorly controlled disease.

Current wording

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.

Previous wording

In March 2025, quality of life data were presented at the American Academy of Allergy, Asthma & Immunology (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.

Current wording

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.

Previous wording

We believe these results strongly support the further development of barzolvolimab in CIndU and plan to advance CIndU into Phase 3 registrational development.

Current wording

We believe these results strongly support the further development of barzolvolimab in CIndU and Celldex plans to initiate a global Phase 3 study in ColdU and SD in December 2025.

Previous wording

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 will include approximately 50 clinical trial centers worldwide, including the United States. Enrollment is ongoing.

Current wording

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 is ongoing. Initial data from this study are expected to be presented in the second half of 2026.

Previous wording

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 will include up to 50 clinical trial centers in the United States. Enrollment is ongoing.

Current wording

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 is ongoing. Initial data from this study are expected to be presented in the second half of 2026.

Previous wording

In 2023, we completed the transfer of our current barzolvolimab manufacturing process to a CDMO and successfully scaled up the drug substance manufacturing process to produce larger cGMP batches 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 are actively being used in the ongoing Phase 3 CSU trials.

Current wording

In 2023, we completed the transfer of our current barzolvolimab manufacturing process to a CDMO and successfully scaled up the drug substance manufacturing process to produce larger cGMP batches 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 are actively being used in the ongoing Phase 3 CSU trials. In the third quarter of 2025, we initiated the Process Performance Qualification (PPQ) manufacturing runs for drug substance and are currently planning for the drug product PPQ activities in 2026.

Previous wording

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. In preclinical studies, CDX-622 inhibits TSLP and SCF with similar potency to both its respective parental mAbs and comparator mAbsin 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.

Current wording

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 mAbsin 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.

Previous wording

In November 2024, we initiated a Phase 1 study of CDX-622 in healthy volunteers. The Phase 1a clinical trial is a two-part, randomized, double-blind, placebo-controlled, dose escalation study designed to assess the safety, pharmacokinetics, and pharmacodynamics of single ascending doses (Part 1) and multiple ascending doses (Part 2) of CDX-622 in up to 56 healthy participants. A single dose of CDX-622 or placebo will be administered intravenously once during Part 1. In Part 2, CDX-622 or placebo will be administered every 2 weeks (Q2W) for up to 6 weeks following the first dose, for a total of 3 doses. Participants will be followed for 12 weeks in both Parts 1 and 2 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. A subcutaneous formulation is currently being manufactured and will be added to this study in 2025. Enrollment is ongoing and we plan to present data from Part 1 of the study in the second half of 2025.

Current wording

In November 2024, we initiated a Phase 1 study of CDX-622 in healthy volunteers. 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 single ascending doses (Part 1), multiple ascending doses (Part 2) and single ascending doses administered subcutaneously (Part 3) of CDX-622 in up to 80 healthy participants. A single dose of CDX-622 or placebo was administered intravenously once during Part 1. In Part 2, CDX-622 or placebo is administered every 2 weeks (Q2W) for up to 6 weeks following the first dose, for a total of 3 doses. A single dose of CDX-622 or placebo will be administered subcutaneously once during Part 3. Participants will be 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. A subcutaneous formulation is currently being manufactured and will be added to this study in 2025.

Previous wording

The $20.8 million increase in net loss for the three months ended June 30, 2025, as compared to the three months ended June 30, 2024, was primarily due to an increase in research and development expenses and a decrease in investment and other income, net.

Current wording

The $24.9 million increase in net loss for the three months ended September 30, 2025, as compared to the three months ended September 30, 2024, was primarily due to an increase in research and development expenses related to barzolvolimab and decreases in revenue and investment and other income, net.

Previous wording

Revenue from product development and licensing agreements for the three months ended June 30, 2025 was relatively consistent with the three months ended June 30, 2024. The $1.8 million decrease in contracts and grants revenue for the three months ended June 30, 2025, as compared to the three months ended June 30, 2024, was primarily due to a decrease in revenue from our contract manufacturing and research and development agreements with Rockefeller University. We expect revenue to decrease over the next twelve months primarily due to a decrease in services expected to be performed under our contract manufacturing and research and development agreements with Rockefeller University.

Current wording

Revenue from product development and licensing agreements for the three months ended September 30, 2025 was relatively consistent with the three months ended September 30, 2024. The $3.2 million decrease in contracts and grants revenue for the three months ended September 30, 2025, as compared to the three months ended September 30, 2024, was primarily due to a decrease in revenue from our contract manufacturing and research and development agreements with Rockefeller University. We expect revenue to remain relatively consistent over the next twelve months, although there may be fluctuations on a quarterly basis.

Previous wording

Personnel expenses primarily include salary, benefits, stock-based compensation and payroll taxes. The $2.2 million increase in personnel expenses for the three months ended June 30, 2025, as compared to the three months ended June 30, 2024, was primarily due to higher stock-based compensation expense and an increase in employee headcount. We expect personnel expenses to increase over the next twelve months as a result of additional headcount to support the expanded development of barzolvolimab.

Current wording

Personnel expenses primarily include salary, benefits, stock-based compensation and payroll taxes. The $0.6 million increase in personnel expenses for the three months ended September 30, 2025, as compared to the three months ended September 30, 2024, was primarily due to an increase in employee headcount. We expect personnel expenses to increase over the next twelve months as a result of additional headcount to support the expanded development of barzolvolimab.

Previous wording

Laboratory supplies expenses include laboratory materials and supplies, services, and other related expenses incurred in the development of our technology. Laboratory supply expenses for the three months ended June 30, 2025 were relatively consistent with the three months ended June 30, 2024. We expect laboratory supplies expenses to remain relatively consistent over the next twelve months, although there may be fluctuations on a quarterly basis.

Current wording

Laboratory supplies expenses include laboratory materials and supplies, services, and other related expenses incurred in the development of our technology. Laboratory supply expenses for the three months ended September 30, 2025 were relatively consistent

Previous wording

Facility expenses include depreciation, amortization, utilities, rent, maintenance and other related expenses incurred at our facilities. Facility expenses for the three months ended June 30, 2025 were relatively consistent with the three months ended June 30, 2024. We expect facility expenses to remain relatively consistent over the next twelve months, although there may be fluctuations on a quarterly basis.

Current wording

Facility expenses include depreciation, amortization, utilities, rent, maintenance and other related expenses incurred at our facilities. Facility expenses for the three months ended September 30, 2025 were relatively consistent with the three months ended September 30, 2024. In September 2025, we signed a new lease in New Haven, CT that we will relocate our existing New Haven operations to in 2026. We expect facility expenses to increase over the next twelve months, although there may be fluctuations on a quarterly basis.

Previous wording

Product development expenses include clinical investigator site fees, external trial monitoring costs, data accumulation costs, contracted research and outside clinical drug product manufacturing. The $10.9 million increase in product development expenses for the three months ended June 30, 2025, as compared to the three months ended June 30, 2024, was primarily due to an increase in barzolvolimab clinical trial and contract manufacturing expenses. We expect product development expenses to increase over the next twelve months as a result of the expanded development of barzolvolimab, although there may be fluctuations on a quarterly basis.

Current wording

Product development expenses include clinical investigator site fees, external trial monitoring costs, data accumulation costs, contracted research and outside clinical drug product manufacturing. The $15.8 million increase in product development expenses for the three months ended September 30, 2025, as compared to the three months ended September 30, 2024, was primarily due to an increase in barzolvolimab clinical trial and contract manufacturing expenses. We expect product development expenses to increase over the next twelve months as a result of the expanded development of barzolvolimab, including manufacturing PPQ activities planned for the fourth quarter of 2025 and throughout 2026, although there may be fluctuations on a quarterly basis.

Previous wording

The $1.3 million increase in general and administrative expenses for the three months ended June 30, 2025, as compared to the three months ended June 30, 2024, was primarily due to higher stock-based compensation expense and an increase in employee headcount. We expect general and administrative expenses to increase over the next twelve months as a result of the expanded development of barzolvolimab and an increase in commercial planning efforts, although there may be fluctuations on a quarterly basis.

Current wording

The $0.6 million increase in general and administrative expenses for the three months ended September 30, 2025, as compared to the three months ended September 30, 2024, was primarily due to higher commercial planning expenses. We expect general and administrative expenses to increase over the next twelve months as a result of the expanded development of barzolvolimab and an increase in commercial planning efforts, although there may be fluctuations on a quarterly basis.

Previous wording

The $3.2 million decrease in investment and other income, net for the three months ended June 30, 2025, as compared to the three months ended June 30, 2024, was primarily due to lower levels of cash and investment balances. We expect investment and other income to decrease over the next twelve months due to lower levels of cash and investment balances, although there may be fluctuations on a quarterly basis.

Current wording

The $3.4 million decrease in investment and other income, net for the three months ended September 30, 2025, as compared to the three months ended September 30, 2024, was primarily due to lower levels of cash and investment balances. We expect investment and other income to decrease over the next twelve months due to lower levels of cash and investment balances, although there may be fluctuations on a quarterly basis.

Previous wording

The $41.7 million increase in net loss for the six months ended June 30, 2025, as compared to the six months ended June 30, 2024, was primarily due to an increase in research and development expenses related to barzolvolimab.

Current wording

The $66.7 million increase in net loss for the nine months ended September 30, 2025, as compared to the nine months ended September 30, 2024, was primarily due to an increase in research and development expenses related to barzolvolimab and decreases in revenue and investment and other income, net.

Previous wording

Revenue from product development and licensing agreements for the six months ended June 30, 2025 was relatively consistent with the six months ended June 30, 2024. The $1.3 million decrease in contracts and grants revenue for the six months ended June 30, 2025, as compared to the six months ended June 30, 2024, was primarily due to a decrease in revenue from our contract manufacturing and research and development agreements with Rockefeller University.

Current wording

Revenue from product development and licensing agreements for the nine months ended September 30, 2025 was relatively consistent with the nine months ended September 30, 2024. The $4.5 million decrease in contracts and grants revenue for the nine months ended September 30, 2025, as compared to the nine months ended September 30, 2024, was primarily due to a decrease in revenue from our contract manufacturing and research and development agreements with Rockefeller University.

Previous wording

Personnel expenses primarily include salary, benefits, stock-based compensation and payroll taxes. The $4.4 million increase in personnel expenses for the six months ended June 30, 2025, as compared to the six months ended June 30, 2024, was primarily due to higher stock-based compensation expense and an increase in employee headcount.

Current wording

Personnel expenses primarily include salary, benefits, stock-based compensation and payroll taxes. The $5.0 million increase in personnel expenses for the nine months ended September 30, 2025, as compared to the nine months ended September 30, 2024, was primarily due to higher stock-based compensation expense and an increase in employee headcount.

Previous wording

Laboratory supplies expenses include laboratory materials and supplies, services, and other related expenses incurred in the development of our technology. The $0.8 million increase in laboratory supply expenses for the six months ended June 30, 2025, as compared to the six months ended June 30, 2024, was primarily due to higher laboratory materials and supplies purchases.

Current wording

Laboratory supplies expenses include laboratory materials and supplies, services, and other related expenses incurred in the development of our technology. The $0.8 million increase in laboratory supply expenses for the nine months ended September 30, 2025, as compared to the nine months ended September 30, 2024, was primarily due to higher laboratory materials and supplies purchases.

Previous wording

Facility expenses include depreciation, amortization, utilities, rent, maintenance and other related expenses incurred at our facilities. The $0.3 million increase in facility expenses for the six months ended June 30, 2025, as compared to the six months ended June 30, 2024, was primarily due to higher depreciation expense.

Current wording

Facility expenses include depreciation, amortization, utilities, rent, maintenance and other related expenses incurred at our facilities. The $0.4 million increase in facility expenses for the nine months ended September 30, 2025, as compared to the nine months ended September 30, 2024, was primarily due to higher repairs and depreciation expense.

Previous wording

Product development expenses include clinical investigator site fees, external trial monitoring costs, data accumulation costs, contracted research and outside clinical drug product manufacturing. The $27.5 million increase in product development expenses for the six months ended June 30, 2025, as compared to the six months ended June 30, 2024, was primarily due to an increase in barzolvolimab clinical trial and contract manufacturing expenses.

Current wording

Product development expenses include clinical investigator site fees, external trial monitoring costs, data accumulation costs, contracted research and outside clinical drug product manufacturing. The $43.3 million increase in product development expenses for the nine months ended September 30, 2025, as compared to the nine months ended September 30, 2024, was primarily due to an increase in barzolvolimab clinical trial and contract manufacturing expenses.

Previous wording

The $3.0 million increase in general and administrative expenses for the six months ended June 30, 2025, as compared to the six months ended June 30, 2024, was primarily due to higher stock-based compensation and an increase in employee headcount.

Current wording

The $3.6 million increase in general and administrative expenses for the nine months ended September 30, 2025, as compared to the nine months ended September 30, 2024, was primarily due to higher stock-based compensation and an increase in employee headcount.

Previous wording

The $2.1 million decrease in investment and other income, net for the six months ended June 30, 2025, as compared to the six months ended June 30, 2024, was primarily due to lower levels of cash and investment balances.

Current wording

The $5.5 million decrease in investment and other income, net for the nine months ended September 30, 2025, as compared to the nine months ended September 30, 2024, was primarily due to lower levels of cash and investment balances.

Previous wording

At June 30, 2025, our principal sources of liquidity consisted of cash, cash equivalents and marketable securities of $630.3 million. We have had recurring losses and incurred a loss of $110.4 million for the six months ended June 30, 2025. Net cash used in operations for the six months ended June 30, 2025 was $98.4 million. We believe that the cash, cash equivalents and marketable securities at June 30, 2025 are sufficient to meet estimated working capital requirements and fund current planned operations through 2027. This could be impacted if we elect to pay the future milestone under the Settlement Agreement with SRS in cash, in the event that we achieve the milestone related to that payment.

Current wording

At September 30, 2025, our principal sources of liquidity consisted of cash, cash equivalents and marketable securities of $583.2 million. We have had recurring losses and incurred a loss of $177.4 million for the nine months ended September 30, 2025. Net cash used in operations for the nine months ended September 30, 2025 was $147.0 million. We believe that the cash, cash equivalents and marketable securities at September 30, 2025 are sufficient to meet estimated working capital requirements and fund current planned operations through 2027. This could be impacted if we elect to pay the future milestone under the Settlement Agreement with SRS in cash, in the event that we achieve the milestone related to that payment.

Previous wording

Net cash used in operating activities was $98.4 million for the six months ended June 30, 2025 as compared to $70.0 million for the six months ended June 30, 2024. The increase in net cash used in operating activities was primarily due to increases in research and development and general and administrative expenses. We expect that cash used in operating activities will increase over the next twelve months as a result of the expanded development of barzolvolimab.

Current wording

Net cash used in operating activities was $147.0 million for the nine months ended September 30, 2025 as compared to $125.3 million for the nine months ended September 30, 2024. The increase in net cash used in operating activities was primarily due to increases in research and development and general and administrative expenses, partially offset by a decrease in advance payments to clinical research and contract manufacturing organizations. We expect that cash used in operating activities will increase over the next twelve months as a result of the expanded development of barzolvolimab.

Previous wording

Net cash provided by investing activities was $92.8 million for the six months ended June 30, 2025 compared to net cash used in investing activities of $361.9 million for the six months ended June 30, 2024. The increase in net cash provided by investing activities was primarily due to net sales and maturities of marketable securities of $93.8 million for the six months ended June 30, 2025 as compared to net purchases of marketable securities of $361.3 million for the six months ended June 30, 2024.

Current wording

Net cash provided by investing activities was $153.6 million for the nine months ended September 30, 2025 compared to net cash used in investing activities of $314.2 million for the nine months ended September 30, 2024. The increase in net cash provided by investing activities was primarily due to net sales and maturities of marketable securities of $155.1 million for the nine months ended September 30, 2025 as compared to net purchases of marketable securities of $313.0 million for the nine months ended September 30, 2024.

Previous wording

Net cash provided by financing activities was $0.3 million for the six months ended June 30, 2025 as compared to $439.8 million for the six months ended June 30, 2024. The decrease in net cash provided by financing activities was primarily due to a decrease in net proceeds from stock issuances.

Current wording

Net cash provided by financing activities was $1.0 million for the nine months ended September 30, 2025 as compared to $441.1 million for the nine months ended September 30, 2024. The decrease in net cash provided by financing activities was primarily due to a decrease in net proceeds from stock issuances.