Efficacy of Letermovir for Cytomegalovirus Prophylaxis in Heart Transplant Recipients with Moderate to High-Risk CMV Serostatus.
Academic Article
Overview
abstract
BACKGROUND: Cytomegalovirus (CMV) infection post heart transplantation (HT) is associated with worse outcomes. Antiviral prophylaxis for at-risk patients is standard of care. Valganciclovir, the most commonly used antiviral, is associated with significant adverse events, particularly leukopenia. Letermovir is a CMV-specific anti-viral with a favorable side effect profile but its efficacy in HT recipients is unclear. This study aims to assess the safety and efficacy of letermovir for CMV prophylaxis in HT recipients. METHODS: This single-center retrospective analysis included HT recipients at our center from January 2020-September 2023. Patients who were switched to letermovir for CMV prophylaxis for leukopenia/neutropenia on valganciclovir, and 1) remained on letermovir for at least 60 days or 2) developed CMV viremia on letermovir within 60 days of initiation were included. Primary endpoint was incidence of CMV viremia/disease during letermovir therapy. Secondary endpoints included changes in white blood cell (WBC) count, tacrolimus dosing, and clinically significant acute rejection. RESULTS: Fifty-two patients received letermovir for an average of 8.2 months (range 1 to 35 months). Average time from transplant to letermovir initiation was 9.2 months, (range 0.9 to 77 months). Eight (15.4%) patients developed breakthrough CMV viremia on letermovir with a median viral load of 205 [IQR 142-367.5] copies/mL, and 4 of these patients were converted back to valganciclovir; overall 92.3% of patients completed therapy with letermovir. There were no episodes of suspected or biopsy-proven, CMV disease. Majority of patients (78%) required dose reductions of tacrolimus following letermovir initiation with no episodes of tacrolimus toxicity requiring hospitalization. WBC counts increased, on average, from 2.6 to 5.3 × 103 cells/μL, p <0.001. CONCLUSIONS: Letermovir holds promise as an effective and safe alternative to valganciclovir for CMV prophylaxis in HT recipients.
