Bone Marrow Transplantation HLA Haploidentical After a Reduced Intensity Conditioning and Prevention of GvHD Based on Post-transplant Cyclophosphamide Administration in Patients With Severe Sickle Cell Disease

Sickle cell disease is a severe disease with frequent occurrence of painful crises and progressive installation of a multi organ injuries. Despite the progress in its management, particularly since the introduction of hydroxycarbamide, the median age of death in sickle cell patients was about 40 years in a recent US study. Severe forms resistant to hydroxyurea or cerebral vasculopathy require transfusion programs throughout susceptible to risks of iron overload and alloimmunization. The bone marrow transplantation cures almost 95% of children and adolescents transplant from an HLA-identical siblings. In patients without HLA-identical donor, interesting results have been reported in haploidentical transplants marrow without ex vivo T cell depletion taken after non myeloablative conditioning regimen and GvHD prevention with cyclophosphamide high dose injection after bone marrow transplant . This approach performed in 14 patients was effective to cure 50% of the patients and 50% have rejected the transplant . No death or severe GvHD were related to the procedure.

DREPHAPLO protocol aims to evaluate that approach in a population of sickle cell patients with severe complications of the disease, bringing direct benefit to patients with a cure of the disease in at least half of them.