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Published on: September 20, 2021
Suppressive therapy versus episodic therapy with oral valacyclovir for recurrent herpes labialis: efficacy and
1Department of Medicine, Division of Dermatology, University of Washington, Dermatology and Laser Center, Bellingham, WA 98225, USA. scgilbert@hinet.org
Abstract:
Oral valacyclovir's efficacy and tolerability as suppressive therapy versus episodic therapy were compared for recurrent herpes labialis (RHL). Subjects with a history of at least 3 RHL episodes in the past year were randomized to receive 6 months of oral valacyclovir episodic therapy at the first sign of prodrome (two 2-g doses separated by 12 hours) and 6 months of oral valacyclovir suppressive therapy (1 g once daily) for 6 months in open-label, crossover fashion. The mean +/- SE number of recurrences per 120 days of follow-up (primary endpoint) was lower with suppressive therapy (0.30 +/- 0.41) than episodic therapy (0.71 +/- 0.79) (P < .005). The probability of remaining recurrence free over 6 months was significantly higher with suppressive therapy than episodic therapy. The median time to first recurrence was 81 days with episodic therapy and was not calculable (> 180 days) for suppressive therapy (P = 0.021). Data for secondary efficacy endpoints (pain severity score, mean duration of recurrences, maximal total lesion area) showed approximately a 30% to 50% reduction in mean values with suppressive therapy compared with episodic therapy, but results were statistically significantly different between the regimens for pain severity only. The percentage of subjects with at least one adverse event over 6 months of treatment that was considered to be drug related was 3% with suppressive therapy and 6% with episodic therapy. Suppressive therapy with oral valacyclovir was more effective than episodic therapy with oral valacyclovir in reducing the frequency of recurrences of herpes labialis and prolonging the time to first recurrence and was also similarly well-tolerated.
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