Adebrelimab Combined With Trametinib in the Treatment of Refractory Recurrent Langerhans Cell Histiocytosis in Children and Adolescents

Phase 1, 1 case in total Subject 1: This study marks the first application of Adebrelimab in pediatric patients with Langerhans Cell Histiocytosis (LCH). The initial dose is 20 mg/kg, delivered via a 60-minute intravenous infusion. If no Dose-Limiting Toxicity (DLT) occurs, the second dose of 20 mg/kg will be administered in the second cycle. Treatment cycles consist of dosing every 4 weeks, up to a maximum of 6 cycles. Phase 2, 2-5 cases in total Subjects 2 and 3: If the first subject exhibits no DLT, the second and third subjects will be enrolled and receive 20 mg/kg of Adebrelimab on day 1. Treatment cycles will last 4 weeks, with dosing administered every 4 weeks, for up to 6 cycles. Subjects 4-6: If one DLT occurs among the first three subjects, three additional subjects will be enrolled and given 20 mg/kg of Adebrelimab. If two or more DLTs occur among the first three subjects, three additional subjects will be enrolled and administered a reduced dose of 10 mg/kg. Following the successful completion of these phases, a subsequent phase will commence to further assess the efficacy and safety of Adebrelimab and fulfill the biological research objectives.

NCT Number	NCT06902792
Lead Sponsor	Second Affiliated Hospital of Wenzhou Medical University
Conditions	Histiocytosis, Langerhans-Cell
Enrollment	6 participants
Start Date	2025-02-06
Primary Completion	2025-08-06 (estimated)
Study Completion	2026-02-02 (estimated)
Updated on ClinicalTrials.gov	2025-03-30