HLA-Matched Related Versus Haploidentical Peripheral Blood Stem Cell Transplantation in Adults and Children. Real World Outcomes in Mexico

Abstract

Introduction In low to middle income countries access to matched unrelated donors and umbilical cord blood for allogeneic transplantation (HSCT) is limited. Haploidentical transplantation (Haplo) with post-transplant cyclophosphamide (PTCy) has increased access to HSCT for patients without a matched sibling (MSD) at an affordable cost, becoming our preferred strategy. Objectives We aim to compare MSD vs Haplo peripheral blood (PB) HSCT outcomes in a center without access to alternative donors. Methods This was a prospective and comparative single center study including adults and children with hematological malignancies. Patients without an MSD directly proceeded to Haplo HSCT with versus Haplo donor randomization. PB was used in all cases with either myeloablative (MAC) or reduced-intensity conditioning (RIC). Graft-versus-host disease (GVHD) prophylaxis was performed with a calcineurin inhibitor (CI) plus methotrexate or post-transplant cyclophosphamide plus CI and mycophenolate. Standard outcomes were compared according to HLA match. Results 112 patients were grafted in 2016-2018, 74.1% received Haplo grafts, 25.9% were MSD. Patients who received Haplo grafts were younger with a median age of 19 years (range 3-66) vs. 39 years for MSD (range 3-66) (p Conclusions Haploidentical transplantation with PTCy has allowed us to triple our transplant rates, at the cost of delayed platelet engraftment and increased primary graft failure. Haplo patients were younger, receiving more CD34+ cells, and although unpowered, promising outcomes comparable to MSD were observed supporting our strategy.