Benefits of primary prophylaxis with letermovir in patients after allogeneic hematopoietic stem cell transplantation for hematologic malignancies.

Abstract

Background: Introduction of letermovir (LMV) as prophylaxis for cytomegalovirus (CMV) infection has decreased the number of clinically significant CMV infections (cs-CMVi) in allogeneic hematopoietic stem cell transplantation (HSCT) recipients. However, long-term, real-world data on LMV's impact on post-transplant outcome remain scarce.

Research design and methods: The aim of our study was to evaluate clinical outcome of 93 CMV-seropositive patients who received LMV prophylaxis and to compare them to 168 LMV-free recipients.

Results: CMV reactivation was less frequently observed in LMV group if compared to LMV-free control. Twelve patients (17%) and 71 (42%) reactivated CMV in LMV-treated and LMV-free patients, respectively. The cumulative incidence of cs-CMVi was lower in LMV group compared to control [37% vs. 63%]. The incidence of severe acute graft-versus-host disease (aGVHD) was also lower in LMV-treated patients (6% vs. 21%). Overall survival, non-relapse mortality and progression-free survival at 24 months were comparable. No risk factors for post-transplant CMV reactivation were identified in LMV group, whereas unrelated donor, donor-negative/recipient-positive CMV-serostatus, and presence of severe aGVHD were associated with higher risk of CMV reactivation in LMV-free control.

Conclusions: LMV as CMV primary prophylaxis has a beneficial effect on post HSCT outcome decreasing the incidence of severe aGVHD and cs-CMV reactivation.