Refractory Langerhans Cell Histiocytosis

This phase I trial tests the safety, side effects, and best dose of Q702 in treating patients with hematologic malignancies. Q702 is in a class of medications called immunomodulatory agents. It works by helping the immune system kill cancer cells and by helping the bone marrow to produce normal blood cells. Giving Q702 may be safe, tolerable and/or effective in treating patients with hematologic malignancies.

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.

This is a single-arm study to evaluate the efficacy and safety of CD207 targeted CAR-T cell therapy in relapsed and refractory langerhans cell histiocytosis.