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Valacyclovir (ZELITREX)
Valacyclovir is a prodrug that is converted to acyclovir, which inhibits viral DNA polymerase to prevent herpesvirus replication.
Valacyclovir is a prodrug that is converted to acyclovir, which inhibits viral DNA polymerase to prevent herpesvirus replication. Used for Herpes simplex virus (HSV-1 and HSV-2) infection, including genital herpes and cold sores, Varicella-zoster virus (VZV) infection, including shingles (herpes zoster) and chickenpox, Cytomegalovirus (CMV) prophylaxis in immunocompromised patients.
At a glance
| Generic name | Valacyclovir (ZELITREX) |
|---|---|
| Sponsor | Assistance Publique - Hôpitaux de Paris |
| Drug class | Nucleoside analog antiviral |
| Target | Viral DNA polymerase (herpesvirus) |
| Modality | Small molecule |
| Therapeutic area | Infectious Disease / Virology |
| Phase | FDA-approved |
Mechanism of action
Valacyclovir is rapidly metabolized to acyclovir in the body. Acyclovir is phosphorylated by viral thymidine kinase in infected cells, then further phosphorylated to the active triphosphate form, which competitively inhibits viral DNA polymerase and causes chain termination of viral DNA synthesis. This selectively targets herpesvirus-infected cells while sparing uninfected cells.
Approved indications
- Herpes simplex virus (HSV-1 and HSV-2) infection, including genital herpes and cold sores
- Varicella-zoster virus (VZV) infection, including shingles (herpes zoster) and chickenpox
- Cytomegalovirus (CMV) prophylaxis in immunocompromised patients
Common side effects
- Headache
- Nausea
- Abdominal pain
- Diarrhea
- Tremor (at high doses)
- Confusion or hallucinations (rare, high-dose)
Key clinical trials
- Virus-Based Gene Therapy (AdV-HSV1-TK and AdV-Flt3L) in Combination With Valacyclovir for the Treatment of Pediatric and Young Adult Patients With Resectable, Recurrent Primary Malignant Brain Tumors (PHASE1)
- GMCI, Nivolumab, and Radiation Therapy in Treating Patients With Newly Diagnosed High-Grade Gliomas (PHASE1)
- Bioequivalence Study in Healthy Volunteers of a New Paediatric Formulation of Valacyclovir (PHASE1)
- To Rescue Cognition With Valaciclovir (PHASE2)
- CMV Modulation of the Immune System in ANCA-associated Vasculitis (PHASE2)
- In UTERO Treatment of Cytomegalovirus Congenital Infection With Valacyclovir (PHASE4)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |