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Letermovir IV

Merck Sharp & Dohme LLC · Phase 3 active Small molecule

Letermovir inhibits the viral terminase enzyme of cytomegalovirus (CMV), preventing viral DNA packaging and replication.

Letermovir inhibits the viral terminase enzyme of cytomegalovirus (CMV), preventing viral DNA packaging and replication. Used for CMV prophylaxis in CMV-seronegative recipients of allogeneic hematopoietic stem cell transplant from CMV-seropositive donors, CMV infection and disease in immunocompromised patients (treatment).

At a glance

Generic nameLetermovir IV
Also known asMK-8228, PREVYMIS®
SponsorMerck Sharp & Dohme LLC
Drug classCMV terminase inhibitor
TargetCMV UL56 terminase
ModalitySmall molecule
Therapeutic areaInfectious Disease / Virology
PhasePhase 3

Mechanism of action

Letermovir is a first-in-class CMV terminase inhibitor that blocks the UL56 terminase protein, which is essential for packaging CMV DNA into virions. By inhibiting this viral enzyme, the drug prevents the formation of infectious CMV particles and reduces viral replication in infected cells. This mechanism is distinct from nucleoside analogs and allows for use in prophylaxis and treatment of CMV infection.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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