A phase II study of low dose melphalan with thiotepa and fludarabine as preparative regimen for alternative donor transplantation.

We conducted a phase II study of fludarabine, thiotepa, reduced dose melphalan conditioning for allogeneic transplantation using alternate donors. Thirty-eight patients with hematological malignancies were enrolled. Conditioning included fludarabine 160 mg/m2, thiotepa 10 mg/kg (dose adjusted to 5 mg/kg for age >60 years) and melphalan 100 mg/m2. Sixteen patients (42%) received reduced intensity thiotepa (5 mg/kg). Twenty-one patients (55%) had acute myeloid leukemia, rest had acute lymphoblastic leukemia, myelodysplastic syndrome, myelofibrosis and relapsed high-risk lymphomas. Twenty-eight (74%) underwent haplo-identical transplants-rest received double cord blood grafts. With median follow up of 38 months, Day +100 marrow demonstrated morphologic complete remission in 34/38 evaluable patients. Progression-free survival at 1-, 2- and 3-year was 68%, 63% and 63%, respectively. Overall survival at 1-, 2- and 3-year was 76%, 71% and 64%, respectively. One-year non-relapse mortality was 21% and relapse rate was 11%. Twelve patients received post-transplant maintenance therapy. We conclude that fludarabine/thiotepa/low dose melphalan can induce durable long-term remissions in patients with advanced disease.