Impact of Prior Chimeric Antigen Receptor T-Cell Treatment on Graft-Versus-Host Disease and Nonrelapse Mortality after Allogeneic Transplantation

It remains unclear whether prior chimeric antigen receptor (CAR) T-cell therapy is associated with an increased risk of graft-versus-host disease (GVHD) or nonrelapse mortality (NRM) following allogeneic hematopoietic cell transplantation (HCT). We evaluated the incidence of NRM, acute GVHD, and chronic GVHD in patients who underwent HCT following CAR T-cell therapy compared with matched controls who did not receive CAR T-cell therapy prior to HCT. We conducted a retrospective propensity-score matched case (prior CAR T recipients)-control (no CAR T prior to HCT) study to describe the impact of prior CAR T treatment on HCT outcomes. Day-100 NRM in the case versus control groups were 6.2% versus 8.6% (P = .82). Day-100 CI of grades II to IV and III to IV acute GVHD in the case versus control groups were 43.1% versus 44.8% (P = .83) and 20.0% versus 12.1% (P = .099), respectively. The 1-year CI of any and moderate/severe chronic GVHD in the case versus control groups were 43.8% versus 42.3% (P = .87) and 28.1% versus 20.3% (P = .23), respectively. Overall and GVHD/relapse-free survival were not statistically significantly different after adjusting for DRI, P = .094 and P = .14, respectively. The cumulative incidence of relapse and disease-free survival were not statistically significantly different. Patients who had less than 3 months between CAR T and HCT had improved graft-versus-host disease/relapse-free survival (GRFS), 40% versus 24.4% at 1-year (P = .032), owing to reduced grade III to IV acute GVHD, 5% versus 26.7% at 100-d (P = .030). Prior CAR T-cell therapy was not associated with an increased risk of GVHD or NRM, suggesting that CAR T-cell therapy can be administered without adversely affecting subsequent HCT outcomes.