Famvir

Famciclovir tablets
NOVARTIS
Antiviral approved for 1-day treatment of recurrent genital herpes

A prodrug of penciclovir, famciclovir is ultimately phosphorylated by the viral thymidine kinase and subsequently cellular kinases to a penciclovir triphosphate, which inhibits herpes simplex 2 (HSV-2) DNA polymerase in a competitive manner. Famciclovir was approved on July 28, 2006, in a 1-day dosing regimen for the treatment of recurrent genital herpes.

Efficacy. The efficacy of famciclovir administered in a 1-day regimen for the treatment of recurrent genital herpes was evaluated in a trial of 329 immunocompetent adults. Patients were randomized to either famciclovir 1,000 mg BID or placebo for 1 day. Initiation of treatment occurred within 6 hours of either symptom onset or lesion appearance. Among patients with non-aborted lesions, the median time to healing (from start of therapy to re-epithelialization) was 1.8 days shorter in famciclovir-treated patients than in patients receiving placebo (4.3 days vs 6.1 days, respectively). The median difference in time to healing between the famciclovir and placebo treatment groups was 1.2 days (95% CI, 0.5–2.0). Famciclovir-treated patients experienced aborted lesions (no development beyond erythema) at a rate of 23% versus 13% for patients receiving placebo. The median time to loss of all symptoms (eg, burning, itching, pain, tenderness, tingling) was 3.3 days in patients receiving famciclovir compared with 5.4 days in patients receiving placebo. The efficacy of famciclovir has not been established for initial episode genital herpes infection.

Dosing. The recommended dosage of famciclovir for the treatment of recurrent genital herpes is 1,000 mg BID for 1 day. Therapy should be initiated at the first sign or symptom if medical management of a genital herpes recurrence is indicated. The efficacy of famciclovir has not been established when treatment is initiated more than 6 hours after onset of symptoms or lesions.