Extending postgrafting cyclosporine decreases the risk of severe graft-versus-host disease after nonmyeloablative hematopoietic cell transplantation.

BACKGROUND It is unknown whether the duration of systemic immunosuppressive treatment after allogeneic nonmyeloablative hematopoietic cell transplantation (HCT) might influence the incidence, severity, timing, and/or corticosteroid-responsiveness of graft-versus-host disease (GVHD). METHODS We retrospectively analyzed outcomes among 185 patients with hematologic malignancies who were given grafts from HLA-matched related donors following conditioning with 2 Gy total body irradiation alone or in combination with fludarabine between December 1998 and March 2003. Postgrafting immunosuppression consisted of mycophenolate mofetil (days 0-27) in combination with 3 different cyclosporine (CSP) regimens: taper from (A) days 35 to 56 (n=107), (B) days 56 to 77 (n=35), and (C) days 56 to 180 (n=43). RESULTS The overall incidences of grades II-IV and III-IV acute GVHD, and extensive chronic GVHD were 52%, 13%, and 56%, respectively. The duration of CSP prophylaxis did not significantly influence the overall rate of acute GVHD (grade II-IV), extensive chronic GVHD, or non-relapse mortality. However, prolonged administration of CSP (group C) was associated with a significantly decreased hazard of grades III-IV acute GVHD (HR 0.2, 95% CI [0.04, 0.9]) and with an increased likelihood of discontinuing all systemic immunosuppression (HR 2.4, 95% CI [1.1, 5.2]) when compared to the shortest course of CSP (group A). CONCLUSION Longer CSP duration decreased the risk of severe GVHD and increased the likelihood of discontinuing all systemic immunosuppression after nonmyeloablative HCT with HLA-matched related grafts.