NCT06983158

A Clinical Trial of CAP-002 Gene Therapy in Pediatric Patients With Syntaxin-Binding Protein 1 (STXBP1) Encephalopathy

A Phase 1/2a, Open-Label, Multi-Center, Dose-Escalation Trial to Assess Safety, Tolerability, and Efficacy of a Single Dose of CAP-002 Gene Therapy Administered to Pediatric Patients With Syntaxin-Binding Protein 1 (STXBP1) Encephalopathy

• Status: Suspended
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 12 (estimated)
• Sponsor: Capsida Biotherapeutics, Inc. · Industry
• Sex: All
• Age: 18 Months – 7 Years
• Healthy volunteers: Not accepted

Summary

The goal of this clinical trial is to learn about the safety of CAP-002 gene therapy in children with Syntaxin-Binding Protein 1 (STXBP1) Encephalopathy. It will also provide information about whether CAP-002 demonstrates efficacy in treating children with STXBP1 with and without seizures. Participants will have a single infusion of CAP-002, visit the clinic regularly for 2 years for checkups and tests and have seizures recorded in a diary by their caregiver.

Detailed description

This is a Phase 1/2a, FIH, open-label, multi-center, dose-escalation trial to assess the safety, tolerability, and efficacy of a single intravenous (IV) dose of CAP-002 administered to participants with syntaxin-binding protein#1 (STXBP1) encephalopathy ages ≥18 months to \<8 years of age. Approximately 12 participants will be dosed in this trial. Phase 1 is a dose escalation phase that will dose approximately 6 participants divided into 2 cohorts (Cohort 1 and Cohort 2) while Phase 2a will have 1 dose cohort and dose approximately 6 participants. Participants in Phase 1 will be dosed sequentially in each cohort. Phase 2a will allow participants to be dosed concurrently if safety and tolerability data from Phase 1 are deemed acceptable. Participants will receive a single intravenous infusion of CAP-002 and will then be followed for 2 years with safety measures, assessments to measure changes from Baseline in development, language, cognition, motor skills and behavior, a seizure diary and structured caregiver interviews. Upon completion of the study or at the participant's final visit they will be invited to participate in a 3 year safety follow up study.

Conditions

• Developmental and Epileptic Encephalopathy

Interventions

Type	Name	Description
DRUG	gene therapy	Intra-venous gene therapy

Timeline

• Start date: 2025-07-03
• Primary completion: 2028-12-20
• Completion: 2028-12-20
• First posted: 2025-05-21
• Last updated: 2025-10-01

Locations

4 sites across 1 country: United States

Regulatory

• FDA-regulated drug study