Letermovir (Prevymis)
The Pharmacy and Therapeutics Committee approved the addition of Letermovir (Prevymis) to the inpatient formulary February 2022 with use restricted to the infectious diseases (ID) services, unless for primary prophylaxis in patients high-risk all-HSCT patients. Letermovir is a first in class antiviral agent that inhibits CMV replication by targeting the CMV DNA terminase complex (pUL51, pUL56, pUL89).
Efficacy
Letermovir is approved by the Food and Drug Administration (FDA) for cytomegalovirus (CMV) disease prophylaxis in CMV-seropositive recipients (R+) of an allogeneic hematopoietic stem cell transplant (HSCT). The pivotal trial that led to its approval was a phase 3, parallel, multicenter, randomized, double-blind, placebo-controlled trial that assessed the proportion of patients, among patients without detectable CMV DNA at randomization, who had clinically significant CMV infection through week 24 post transplantation. Of the 495 patients with undetectable CMV DNA at randomization, there were less patients in the letermovir group versus placebo who had clinically significant CMV infection by week 24 after transplantation (122 of 325 patients [37.5%] vs. 103 of 170 [60.6%], P < 0.001). Based on this pivotal trial, letermovir prophylaxis demonstrated a significantly lower risk of clinically significant CMV infection compared to placebo in patients undergoing allogeneic HSCT. Additionally, no other regimen is FDA approved for the prophylaxis of CMV infection in HSCT recipients.
Safety
Warnings and precautions include but are not limited to: nausea, diarrhea, vomiting, peripheral edema, cough, headache, fatigue, and abdominal pain.
Uniqueness
Letermovir is a first-in-class antiviral agent that inhibits CMV replication by targeting the CMV DNA terminase complex (pUL51, pUL56, pUL89). Both the intravenous (IV) and oral (PO) dosage forms are indicated for the prophylaxis of CMV infection and disease in adult patients who are CMV-seropositive recipients of an allogeneic HSCT.