Antivirals for management of herpes zoster including ophthalmicus: a systematic review of high-quality randomized controlled trials

Background: There is lack of consensus from randomized controlled trials on the efficacy of antivirals in the management of herpes zoster. Therefore, a systematic review and meta-analysis was undertaken to provide better understanding of effectiveness of antivirals in management of herpes zoster. Methods: A total of 12 randomized controlled trials with 7,277 patients were included in the review. Trials compared one antiviral to another (aciclovir, valaciclovir, famciclovir or brivudin) for a minimum of 7 days in immunocompetent patients presenting with herpes zoster diagnosed within 72 h of symptom onset. Primary outcome was reduction in pain. Results: Compared with aciclovir, valaciclovir showed significant reduction in herpes-zoster-associated pain up to 112 days. The largest risk reduction in pain (36%) was seen at 21-30 days (relative risk [RR] 0.64, 95% CI 0.59, 0.70) with number needed to treat to benefit (NNT) of 3 (95% CI 2.7, 3.8). Famciclovir was also superior to aciclovir with a 46% reduction in risk of pain at 28-30 days (RR 0.54, 95% CI 0.48, 0.68) with NNT of 3 (95% CI 2, 5). Time to lesion healing and adverse effect profile was comparable. Conclusions: Evidence from quality trials have shown significant reduction in risk of pain with valaciclovir and famciclovir for management of herpes zoster including ophthalmicus. Valaciclovir or famciclovir should be preferred treatment options in patients with herpes zoster as they both provide significant reduction in risk of herpeszoster- associated pain. Furthermore, the superior pharmacokinetics and more convenient dosing regimens with the use of valaciclovir and famciclovir clearly make them the preferred treatment option.