A Phase I Study of CDX-622

A Randomized, Double-Blind, Placebo-Controlled, Three-Part, Phase 1a Dose Escalation Clinical Trial to Assess the Safety, Pharmacokinetics, and Pharmacodynamics of CDX-622 in Healthy Participants

This is a study to determine the safety of CDX-622 in healthy participants.

Study Overview

• Status: Completed
• Conditions: Healthy Participants
• Intervention / Treatment: Drug: CDX-622; Drug: Normal Saline

Detailed Description

CDX-622 is a bispecific antibody that binds to stem cell factor (SCF) and thymic stromal lymphopoietin (TSLP).

This study will evaluate the safety, pharmacokinetics, and Pharmacodynamics of IV single ascending doses (Part 1), IV multiple ascending doses (Part 2), and subcutaneous (SC) single ascending doses (Part 3) of CDX-622 in healthy participants.

• Study Type: Interventional
• Enrollment (Actual): 85
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Arizona
    • Tempe, Arizona, United States, 85283
      • Celerion, Inc.

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Key Inclusion Criteria:

• An informed consent signed and dated by the participant.
• Healthy volunteer aged 18-55.
• In generally good health and without significant medical conditions based on physical exam, ECG, and laboratory test results.
• Body mass index (BMI) ≥ 18 kg/m2 to ≤ 32 kg/m2.
• No course of medication, whether prescribed or over the counter, in the 4 weeks before study drug administration.
• Both males and females of childbearing potential must agree to use a medically accepted contraceptive regimen during study and up to 150 days afterwards.
• Not a current smoker (or regular user of any nicotine containing product).
• Willing to follow all study rules.

Key Exclusion Criteria:

• Women who are pregnant or nursing.
• History of anaphylaxis, food allergies, or allergies (chronic or seasonal) requiring prescription medication.
• History of asthma requiring the use of inhaled medication within the past 5 years.
• Vaccination within 4 weeks prior to study drug administration (subjects must agree to avoid vaccination during the study).
• Blood donation (excluding plasma donation) of approximately 500 mL within 56 days prior to Screening.
• Positive urine test for alcohol and drugs of abuse.

Additional protocol defined inclusion and exclusion criteria could apply.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: CDX-622; Eligible participants will receive doses of CDX-622 by IV or SC	Drug: CDX-622; Up to 4 infusions of one of seven dosages of CDX-622 or up to 1 dose by subcutaneous injection of one of three dosages of CDX-622
Placebo Comparator: Normal Saline; Eligible participants will receive doses of Normal Saline by IV or SC	Drug: Normal Saline; Up to 4 infusions or 6 SC injections of normal saline

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety as assessed by Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Trials. Infusion reactions will be graded according to Common Terminology Criteria for Adverse Events (CTCAE) v5.0.	To evaluate the safety profile as determined by the incidence of adverse events in single or multiple ascending doses of CDX-622 or placebo comparator in healthy participants.	Day 1 up to Day 127

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
CDX-622 serum evaluations over time	CDX-622 serum concentrations will be measured at specified visits	Day 1 up to Day 127
CDX-622 biomarker evaluations over time	The effect of CDX-622 on serum tryptase levels and other relevant biomarkers	Day 1 up to Day 127
Measurement of anti-drug antibody development over time	Participants will be monitored for the development of anti-drug antibodies	Day 1 up to Day 127

Collaborators and Investigators

• Sponsor: Celldex Therapeutics

Study record dates

Study Major Dates

• Study Start (Actual): November 1, 2024
• Primary Completion (Actual): April 24, 2026
• Study Completion (Actual): April 24, 2026

Study Registration Dates

• First Submitted: October 18, 2024
• First Submitted That Met QC Criteria: October 18, 2024
• First Posted (Actual): October 21, 2024

Study Record Updates

• Last Update Posted (Actual): May 4, 2026
• Last Update Submitted That Met QC Criteria: April 30, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pharmaceutical Preparations; Crystalloid Solutions; Isotonic Solutions; Solutions; Saline Solution
• Other Study ID Numbers: CDX622-01

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No