Post-transplantation Cyclophosphamide in Haploidentical Stem Cell Allografts Dose Reduction: 50 mg/kg vs 25 mg/kg

Allogeneic hematopoietic cell transplantation (HSCT) is a worldwide recognized therapy for several hematologic malignancies; a modality extensively used around the world due to its effectivity; however, an HLA-matched sibling or unrelated donor is not always available, because of diverse factors such as: ethnic minorities and multiethnic families, socio-economic status, among others. This problem has led to an expansion of the donor pool to include alternative donor sources such as HLA-haploidentical (Haplo) relatives, HLA-mismatched unrelated donors, and HLA-matched or mismatched cord blood.

In the Hematology and Internal Medicine Center of Clinica Ruiz, we have seen that 50% reduced doses of post-transplantation cyclophosphamide (25 mg/Kg) on days +3 and +4 have a favorable effect on patient's survival rates compared to the full 50 mg/Kg doses. Haplo-HSCT can be conducted safely on an outpatient basis, using peripheral blood stem cells, this leading into substantial decreases in the costs. Outpatient-based Haplo-HSCT has turned into the solution of the HSCT most frequent problems in low- and middle-income countries (LMIC): Cost and donor availability. The high dose administration of PT-Cy after transplant can lead into hematological and cardiac, toxicities. There is preliminary information about diminished doses of PTCy, might being equally effective in the prevention of GVHD and substantially less toxic.