Tacrolimus as monotherapy or combined with minidose methotrexate for graft-versus-host disease prophylaxis after allogeneic peripheral blood stem cell transplantation: long-term outcomes

We report long-term outcomes for allogeneic peripheral blood stem cell (PBSC) recipients, evaluating cumulative incidence (CI) of acute and chronic graft-versus-host disease (GVHD), after use of tacrolimus with or without minidose methotrexate for GVHD prophylaxis. From April 1996 to April 1998, 97 adults underwent allogeneic PBSC transplantation. The first 49 received tacrolimus monotherapy as GVHD prophylaxis and the subsequent 48 received combination therapy. The median follow-up for survivors was 67 months. Compared to combination therapy, tacrolimus monotherapy resulted in enhanced neutrophil engraftment, shortened hospitalization, comparable rates of GVHD, and equivalent 100-day survival. The CI of grades II-IV acute GVHD was 35% with tacrolimus and 23% with the combination (P = 0.19). The CI of III-IV GVHD was 22% for tacrolimus and 19% for the combination. CI of chronic GVHD was similar between the two groups (P = 0.5). Patients with good-risk disease had superior overall survival (OS) when compared to those with poor-risk features (P < 0.001). Within the good-risk disease category, patients receiving methotrexate had a trend towards improved OS (P = 0.07). Multivariate analysis indicated good-risk disease status and methotrexate were independently associated with improved OS, progression-free survival (PFS), and relapse. In addition, patients developing chronic GVHD had a significantly reduced risk of relapse and improved PFS.