Abatacept linked to reduced acute GvHD after pediatric stem cell transplantation

A systematic review and meta-analysis in Pediatric Blood & Cancer evaluated abatacept for graft-versus-host disease (GvHD) prophylaxis in children undergoing allogeneic hematopoietic stem cell transplantation. The review included 15 cohort studies—eight comparative and seven single-arm—in which abatacept was added to traditional prophylaxis regimens. Outcomes included acute and chronic GvHD, immune reconstitution, infections, and overall survival. The abstract did not report the total number of patients.

Abatacept-inclusive regimens were associated with lower risks of grade II–IV acute GvHD (risk ratio [RR] 0.31, 95% CI 0.14–0.65) and grade III–IV acute GvHD (RR 0.14, 95% CI 0.05–0.37). Moderate-to-severe chronic GvHD incidence was not reduced overall, although extended abatacept regimens were associated with reduced risk (RR 0.25, 95% CI 0.08–0.78).

The analysis found no association with compromised immune reconstitution or increased viral reactivation. Abatacept-inclusive prophylaxis was associated with fewer bacterial infections (RR 0.39, 95% CI 0.21–0.74) and improved overall survival (RR 1.18, 95% CI 1.03–1.34). These findings support potential benefit as adjunctive prophylaxis, but retrospective study designs and cohort heterogeneity limit causal conclusions. Absolute event rates, follow-up durations, and detailed dosing schedules were not available in the supplied abstract.