Medline ® Abstracts for References 11,12

BACKGROUND: Famciclovir, the well absorbed oral pro-drug of penciclovir, is effective in the treatment of herpes zoster when given three times daily. Because the intracellular half-life of penciclovir triphosphate in varicella-zoster virus (VZV)-infected cells (7h) is considerably longer than that of aciclovir triphosphate (1h), it may be possible to administer famciclovir less frequently than three times daily for herpes zoster: aciclovir is administered five times daily.

METHODS: 559 immunocompetent adults presenting with herpes zoster whose skin lesions were present for less than 72 h were randomized to receive famciclovir 750 mg once daily (od), 500 mg twice daily (bid), or 250 mg three times daily (tid), or aciclovir 800 mg five times daily. All treatments were given for 7 days. Participants were evaluated until complete healing or for 4 weeks, whichever occurred first.

RESULTS: There were no significant differences between the four treatment groups with respect to times to full crusting; loss of vesicles, ulcers and crusts; cessation of new lesion formation; a 50% reduction in the area of affected skin; and the loss of acute pain.

CONCLUSIONS: Famciclovir 750 mg once daily, 500 mg twice daily and 250 mg daily, and aciclovir 800 mg five times daily are three times comparable in efficacy with respect to the cutaneous healing of herpes zoster. The current study was not designed to assess the effects of the treatments on postherpetic neuralgia (PHN).

OBJECTIVE: To compare the efficacy and safety of valacyclovir hydrochloride and famciclovir for the treatment of herpes zoster.

DESIGN: A double-blind, randomized, controlled, multicenter clinical trial in which patients received 7 days of treatment and were followed up for 24 weeks.

SETTINGS: Patients reported directly to specialist centers or were referred from primary care centers.

PATIENTS: There were 597 otherwise healthy immunocompetent outpatients, aged 50 years and older, who presented within 72 hours of onset of zoster rash.

INTERVENTIONS: Treatment with valacyclovir hydrochloride (1 g 3 times daily) or famciclovir (500 mg 3 times daily) for 7 days.

MAIN OUTCOME MEASURES: Resolution of zoster-associated pain and postherpetic neuralgia, rash healing, and treatment safety.

RESULTS: Intent-to-treat analysis did not detect statistically significant differences for valacyclovir vs famciclovir on resolution of zoster-associated pain (hazard ratio, 1. 02; 95% confidence interval, 0.84-1.23; P =.84). Furthermore, no differences were evident between treatments on rash healing rates and on a range of analyses of postherpetic neuralgia. Safety profiles for valacyclovir and famciclovir were similar, with headache and nausea being the more common adverse events.

CONCLUSIONS: Valacyclovir treatment is comparable to famciclovir treatment in speeding the resolution of zoster-associated pain and postherpetic neuralgia. Current wholesale prices indicate that valacyclovir is the more cost-effective treatment for herpes zoster ($83.90 vs $140.70 per course).