Allogeneic CD56 + cell infusion as a bridge to hematopoietic stem cell transplantation in relapsed/refractory acute myeloid leukemia: a phase I clinical trial

BACKGROUND AND PURPOSE: NK/NKT-like cells have demonstrated antileukemic activity and represent a promising platform for the development of novel cellular therapies. STUDY DESIGN: NK/NKT-like cells at 5-day intervals. RESULTS: A total of 11 patients with a median age of 41.5 years were enrolled in the study. On average, they received three lines of prior chemotherapy and showed 18% blasts in their bone marrow. The infusion of CD56⁺ NK/NKT-like cells was safe, with no serious toxicity or graft-versus-host disease (GVHD) observed in any patient. Following this treatment protocol, five patients (45.4%) achieved complete remission (CR), with or without hematologic count recovery. Four of these patients (36.3%) underwent successful HSCT and remained event-free to the end of the follow-up period. CONCLUSION: NK/NKT-like cell infusion is safe and may serve as an effective bridge to HSCT in 36.3% of patients with refractory/relapsed non-M3 AML.