Prophylaxis of graft-versus-host-disease: Systematic evidence-based recommendations of the Brazilian association of hematology, hemotherapy, and cell therapy (ABHH) and the Brazilian society of cellular therapy and bone marrow transplantation (SBTMO).

Graft-versus-host disease, involving from 20%-80% of patients, is one of the main complications of allogeneic hematopoietic cell transplantation contributing significantly to mortality and morbidity. The methodological basis of these graft-versus-host disease prophylaxis guidelines for allogeneic hematopoietic cell transplantation, developed by the Brazilian Association of Hematology, Hemotherapy, and Cell Therapy (ABHH) and the Brazilian Society of Cellular Therapy and Bone Marrow Transplantation (SBTMO), is a review which applied the GRADE process to eleven PICO (population, intervention, comparator, and outcome) questions. These questions address graft-versus-host disease prophylaxis in allogeneic hematopoietic cell transplantation across various settings, including myeloablative and non-myeloablative/reduced-intensity conditioning. The scope encompasses related matched, unrelated matched or mismatched, and haploidentical donors, utilizing both bone marrow and peripheral blood as stem-cell sources. The combination of a calcineurin inhibitor (e.g., cyclosporine or tacrolimus) plus methotrexate or mycophenolate mofetil (MMF) has been the standard graft-versus-host disease prophylaxis regimen for allogeneic hematopoietic cell transplantation. The excellent results of post-transplant cyclophosphamide in haploidentical related donor hematopoietic cell transplantation have led to broader use in human leukocyte antigen-(mis)matched related and unrelated donor grafts. Sirolimus, low-dose antithymocyte globulin (4-6 mg/kg) and more recently abatacept are other drugs used. Hence, this review is meant to be a useful reference tool for clinicians who are dealing with this complex complication.