Post-Transplant cyclophosphamide is associated with increase in Non-CMV Herpesvirus infections in Acute leukemia and MDS patients.

ABSTRACT Background: There is increasing use of post-transplant cyclophosphamide (PTCy) for GVHD prophylaxis for both haploidentical and fully matched transplants. Published studies have reported an increased incidence of CMV infection with the use of PTCy. Limited data exist regarding the incidence and outcomes of infection with non-CMV herpes viruses (NCHV) in this setting. Objective: The aim of this study was to evaluate the cumulative incidence of NCHV infections and the association of NCHV infections with transplant-specific outcomes in patients receiving haploidentical transplant with PTCy(HaploCy), matched sibling donor transplant with PTCy (SibCy) or matched sibling donor transplant with calcineurin inhibitor based prophylaxis (SibCNI). We hypothesized that, like CMV infection, patients receiving haploidentical transplant with PTCy will have higher risk of NCHV infections. Study design: Using the CIBMTR database, we analyzed patients (HaploCy, n=757; SibCNI, n=1605; SibCy, n=403) receiving first hematopoietic stem-cell transplant between 2012 and 2017 for acute myeloid leukemia, acute lymphoblastic leukemia and myelodysplastic syndrome. Results: The cumulative incidence of non-CMV herpes virus infection at six months post-transplant in the HaploCy, SibCy and SibCNI were 13.9% (99%CI=10.8-17.3%), 10.7% (99%CI=7.1-15%), and 5.7% (99%CI=4.3-7.3%), p Conclusions: This study demonstrates that the use of PTCy is associated with increased risk of NCHV infection. Development of NCHV infection is associated with increased non-relapse mortality, especially in HaploCY group. Prospective trials should consider viral surveillance strategies in conjunction with assessment of immune reconstitution for better understanding of the clinical relevance of viral reactivation in different transplant settings.