Low-dose PTCy + alemtuzumab for GvHD prevention

A prospective, single-center study evaluated reduced-dose post-transplant cyclophosphamide (PTCy) (15 [n = 33] or 25 mg/kg [n = 30]) combined with low-dose alemtuzumab + cyclosporine compared with standard of care prophylaxis (control; n = 31) for graft-versus-host disease (GvHD) prophylaxis following 9/10 mismatched unrelated peripheral blood stem cell transplantation (PBSCT) in patients with hematologic malignancies. Results were published by Lazana et al. in Bone Marrow Transplantation.

Key data: Low-dose PTCy reduced cumulative incidence (CI) of acute GvHD (aGvHD) Grade II–IV and III–IV vs control (p = 0.02 and p = 0.006, respectively). The CI of any-grade chronic GvHD (cGvHD) was 17% and 20% in the control and PTCy groups, respectively. Patients treated with the lower PTCy dose had higher non-relapse mortality vs the higher dose (p = 0.02). Cytomegalovirus reactivation was observed in 60% and 55% of patients in the PTCy and control groups, respectively.

Key learning: Low-dose PTCy is effective in reducing GvHD in the mismatched unrelated PBSCT setting. The ability to tailor PTCy dosing based on relapse risk supports a personalized approach to GvHD prophylaxis.