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Placebo to ACV

Merck Sharp & Dohme LLC · Phase 3 active Small molecule

This is a Phase 3 trial comparing placebo to acyclovir (ACV), an antiviral nucleoside analog that inhibits viral DNA polymerase to prevent herpes simplex virus replication.

This is a Phase 3 trial comparing placebo to acyclovir (ACV), an antiviral nucleoside analog that inhibits viral DNA polymerase to prevent herpes simplex virus replication. Used for Herpes simplex virus infection (treatment or suppression), Varicella-zoster virus infection (chickenpox or shingles).

At a glance

Generic namePlacebo to ACV
SponsorMerck Sharp & Dohme LLC
Drug classNucleoside analog antiviral
TargetViral DNA polymerase (HSV/VZV)
ModalitySmall molecule
Therapeutic areaInfectious Disease / Virology
PhasePhase 3

Mechanism of action

Acyclovir is a guanosine analog that is phosphorylated by viral thymidine kinase and then converted to its active triphosphate form, which competitively inhibits viral DNA polymerase and causes chain termination of viral DNA synthesis. This mechanism selectively targets herpes simplex virus (HSV) and varicella-zoster virus (VZV) replication while having minimal effects on host cell DNA synthesis.

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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