Lyndhurst

This trial is a Phase 2 study evaluating axatilimab, an antibody targeting the colony stimulating factor 1 receptor, in participants aged 2 years and older with recurrent or refractory active chronic graft versus host disease cGVHD. These participants have previously received at least two lines of systemic therapy but still have active disease requiring further treatment. The study aims to assess the efficacy, safety, and tolerability of axatilimab at different dose levels in this population. Participants will be randomly assigned to one of three axatilimab dosing regimens administered intravenously. The doses include 0.3 mgkg every two weeks, 1 mgkg every two weeks, or 3 mgkg every four weeks. Treatment cycles last 28 days and may continue for up to two years. This open-label, multicenter study allows participants to receive axatilimab while being closely monitored. During the study, participants will have regular assessments to evaluate treatment response based on established NIH criteria for cGVHD. Researchers will measure overall response rates in the first six cycles as well as throughout the study period of up to two years. Other evaluations include symptom scales, organ-specific responses, medication use changes, laboratory biomarkers, and safety monitoring. Participants are followed for efficacy, tolerability, and adverse events during treatment and for the full study duration.