GVHD Prophylaxis With Methotrexate in Haploidentical HCT Using Posttransplant Cyclophosphamide
Status:
Recruiting
Trial end date:
2025-12-01
Target enrollment:
Participant gender:
Summary
Allogeneic hematopoietic cell transplantation (HCT) is an important therapeutic strategy for
many malignant and benign hematologic diseases. Haploidentical HCT has been increasingly used
in patients lacking a HLA-matched donor due to its prompt availability, possibly lower cost
and results comparable with other donor types. Graft-versus-host disease (GVHD) is the main
cause of morbidity and mortality after HSCT, and prophylactic strategies are routinely used.
In the context of haploidentical HCT, posttransplant cyclophosphamide plus cyclosporine and
mycophenolate mofetil (MMF) is the most common platform used in Brazil. Data comparing MMF
and methotrexate (MTX) as GVHD prophylaxes have proved controversial in other donor types,
yet some large studies have showed that MTX is associated with lower risk of GVHD and
improved long-term outcomes. Moreover, it is known that MMF is a potent inhibitor of natural
killer (NK) cells, possibly interfering with the graft-versus-leukemia effect in
haploidentical HCT. Given the possible advantages and the absence of consistent evidence
regarding safety, efficacy and ideal dosage of MTX as GVHD prophylaxis in this setting, we
propose a phase I / II study evaluating this drug in adult patients with hematologic
malignancies undergoing haploidentical HCT with posttransplant cyclophosphamide.