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Valtrex (valaciclovir)
Valtrex works by inhibiting the replication of herpes simplex virus DNA through interference with viral DNA polymerase.
Valtrex (valaciclovir) is a small molecule nucleoside analog DNA polymerase inhibitor developed by GlaxoSmithKline, currently owned by the same company. It is FDA-approved since 1995 for various herpes simplex virus infections, including genital herpes, herpes labialis, herpes zoster, and others. Valtrex is a patented medication, and its commercial status is not off-patent. Key safety considerations include potential liver damage and interactions with other medications. It is a treatment option for herpes simplex virus infections.
At a glance
| Generic name | valaciclovir |
|---|---|
| Also known as | Valtrex, Zelitrex, Anti-viral drugs, Brand names: Valtrex, Zelitrex |
| Sponsor | GSK |
| Drug class | Herpes Simplex Virus Nucleoside Analog DNA Polymerase Inhibitor |
| Modality | Small molecule |
| Therapeutic area | Immunology |
| Phase | FDA-approved |
| First approval | 1995 |
Mechanism of action
Valacyclovir is an antiviral drug active against -herpes viruses [see Microbiology 12.4)].
Approved indications
- Genital herpes simplex
- Herpes labialis
- Herpes zoster
- Recurrent genital herpes simplex
- Suppression of Recurrent Herpes Simplex Infection
- Suppression of Recurrent Herpes Simplex Infection in HIV
- Varicella
Common side effects
- Headache
- Nausea
- Abdominal pain
- Dizziness
- Fatigue
- Rash
- Vomiting
- Dysmenorrhea
- Arthralgia
- Nasopharyngitis
- Upper respiratory tract infection
- Depression
Key clinical trials
- HSV-tk + Valacyclovir + SBRT + Chemotherapy for Recurrent GBM (PHASE1,PHASE2)
- HSV-tk and XRT and Chemotherapy for Newly Diagnosed GBM (PHASE1,PHASE2)
- A Biomarker Study in Men With Localized Prostate Cancer Treated With Aglatimagene Besadenovec (PHASE2)
- Bortezomib and Rituximab for Patients With Waldenstrom's Macroglobulinemia (PHASE2)
- 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)
- Study of an AAV Mediated Dual-Payload Gene Therapy in Patients With High Grade Glioma (PHASE1,PHASE2)
- Time-limited Triplet Combination of Pirtobrutinib, Venetoclax, and Obinutuzumab for Patients With Treatment-naïve Chronic Lymphocytic Leukemia (CLL) or Richter Transformation (RT) (PHASE2)
- Neonatal Phase 1 Valacyclovir Study (PHASE1)
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 |
|---|---|
| FDA label | Mechanism, indications, dosing, boxed warnings, drug interactions |
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |