In a global, multicenter, randomized, placebo-controlled, phase III clinical trial evaluating the safety and efficacy of letermovir, the investigational antiviral medication prevented clinically significant cytomegalovirus (CMV) infection in CMV-seropositive adult patients undergoing allogeneic hematopoietic cell transplantation (alloHCT).
In the study, letermovir, which works by inhibiting viral replication by targeting the viral terminase complex, was administered once daily, either orally or intravenously, starting as early as the day of alloHCT and no later than 28 days post-transplant. Treatment was continued through approximately 100 days post-transplant.
The primary endpoint was the percentage of participants with clinically significant CMV infection through 24 weeks after transplant.
Complete results of the study will be submitted for presentation at a future conference, according to a press release from Merck, the drug's manufacturer. Letermovir has been granted orphan designation and fast-track designation by the U.S. Food and Drug Administration for the prevention of CMV infection and disease in at-risk populations.
Sources: Merck news release, October 19, 2016; Reuters, October 19, 2016.