Tacrolimus as Prophylaxis for Acute Graft-Versus-Host Disease in Reduced Intensity Cord Blood Transplantation for Adult Patients With Advanced Hematologic Diseases

Background. Myeloablative cord blood transplantation (CBT) for adult patients offers a 90% chance of engraftment with a 50% rate of transplant-related mortality, mostly attributable to infection. We have demonstrated the feasibility of reduced-intensity CBT (RI-CBT) for adult patients, in which cyclosporine was used for acute graft-versus-host disease (GVHD) prophylaxis. Transplantation-related mortality (TRM) was 27% within 100 days. Therefore our objective was to evaluate the feasibility of RI-CBT with tacrolimus as GVHD prophylaxis for adult patients with hematologic malignancies. Methods. Thirty-four patients with a median age of 56.5 years (range; 22–68) with hematologic diseases underwent RI-CBT at Toranomon Hospital between November 2003 and September 2004. Preparative regimen comprised fludarabine 25 mg/m2 on days −7 to −3, melphalan 80 mg/m2 on day –2, and 4 Gy total body irradiation on day −1. GVHD prophylaxis was continuous intravenous infusion of tacrolimus 0.03 mg/kg, starting on day –1. Results. Thirty-one patients achieved neutrophil engraftment at a median of day 20. Median infused total cell dose was 2.4×10E7/kg (range; 1.6–4.8). Thirty-two patients achieved complete donor chimerism at day 60. Grade II–IV acute GVHD occurred in 45% of patients, with a median onset of day 26. Primary disease recurred in five patients, and TRM within 100 days was 12%. Estimated 1-year overall survival was 70%. Conclusion. This study demonstrated the possible improvement in transplant-related mortality by tacrolimus as GVHD prophylaxis in adult RI-CBT recipients.