Tacrolimus Plus PTCy Feasible after HLA-Matched AlloHCT

The two-drug combination of tacrolimus plus post-transplant cyclophosphamide (PTCy) led to similar rates of graft-versus-host disease (GVHD) and relapse-free survival rates among patients who underwent and allogeneic hematopoietic cell transplantation (alloHCT) with either human leukocyte antigen (HLA)-matched related or unrelated donors.

A combination of three post-transplant drugs (PTCy, a calcineurin inhibitor, and mycophenolate mofetil) has long been used for GVHD prophylaxis after HLA-haploidentical alloHCT, the authors explained. “Recently, this combination has been used following HLA-matched alloHCT as well, but the optimal combination of drugs for GVHD prophylaxis in an HLA-matched setting remains unclear.”

In this prospective phase II study, researchers evaluated the safety and efficacy of the less-intense, two-drug PTCy plus tacrolimus combination for GVHD prophylaxis after alloHCT from HLA-matched related donors (MRD) or HLA-matched unrelated donors (MUD).

In this group, the cumulative incidences of acute GVHD at 100 days post-alloHCT were:

  • grade II-IV GVHD: 18% for MRD and 18% for MUD
  • grade III-IV GVHD: 5.9% for MRD and 9.1% for MUD

The cumulative incidences of moderate to severe chronic GVHD at one year were 12% and 9.1% in both the MRD and MUD groups, respectively.

The one-year overall survival rates in the MRD and MUD groups were 88% and 64%, respectively. Rates of GVHD-free, relapse-free survival were similar in the MRD and MUD groups, at 59% and 50%, respectively.