Comparing Extended and Short-term Abatacept Treatment to Prevent Graft Versus Host Disease After Transplants

What this Trial Is About

Researchers are studying patients receiving transplants from donors who are 7 out of 8 human leukocyte antigen HLA matches to see if different dosing schedules of abatacept can improve outcomes. This Phase 2, multicenter, randomized, double-blind trial compares an extended dosing regimen of abatacept to a short-term dosing regimen plus placebo, both added to standard graft-versus-host disease GVHD prevention treatments. The main goal is to evaluate survival free from severe acute GVHD, severe chronic GVHD, and relapse over a follow-up period of at least one year post-transplant. All participants initially receive four abatacept doses on days -1, 5, 14, and 28 relative to transplant. Before the fifth dose, participants are randomly assigned to either continue with four additional abatacept doses extended dosing group or receive four placebo doses instead short-term dosing group. Both groups also receive standard GVHD prophylaxis using calcineurin inhibitors cyclosporine or tacrolimus and methotrexate. The study continues until every participant has reached two years after their transplant. Throughout the study, researchers monitor participants for survival without severe GVHD or relapse at two years, as well as secondary outcomes like severe chronic GVHD, relapse-free survival, and non-relapse mortality. Safety is closely tracked, and the study will be unblinded after the last participant reaches one year post-transplant. Participants are involved in regular follow-ups to assess these outcomes and overall health during the trial period.

Extended vs Short-term Abatacept Dosing for Graft Versus Host Disease Prophylaxis