Evaluation of infectious complications after haploidentical hematopoietic stem cell transplantation with post-transplant cyclophosphamide following reduced-intensity and myeloablative conditioning: a study on behalf of the Francophone Society of Stem Cell Transplantation and Cellular Therapy (SFGM-TC).

Several approaches have been developed to overcome historical barriers associated with poor outcomes in the setting of HLA-haploidentical allogeneic transplantation (HaploSCT). Here, we examine the outcome of patients with various hematological disorders undergoing HaploSCT with high-dose, post-transplantation cyclophosphamide. We performed a retrospective study on 381 patients from 30 centers between January 2013 and December 2015. At the last follow-up, a total of 1058 infectious episodes were diagnosed, affecting 90.3% of the cohort. Median time to first infection was 13 days for bacterial, 32 days for viral and 20 days for fungal infections. Around 41% of these infections were of bacterial origin and 35% of viral origin, among which 48.8% of patients presented CMV reactivation. Median of GVHD relapse-free survival, progression-free survival and overall survival were 7.1 months, 19.9 months and 33.5 months, respectively. HSCT procedure was the primary or contributing cause of death (55.6%), followed by relapse of the original disease (34.2%). Infections accounted for 45.7% of the HSCT-related deaths. The present multicenter data on a large cohort of patients receiving HaploSCT with PTCy confirmed the feasibility of the procedure with an acceptable incidence of infectious complications, not different as compared to other haploidentical platforms or HLA-matched transplantation.