Inhibitory effect of Azone® (1-dodecylazacycloheptan-2-one) on herpes simplex virus. In vivo and in vitro studies

Enhanced activity of antiviral agents, when mixed with a penetration enhancer like Azone® (1-dodecylazacycloheptan-2-one) in topical preparations, is well-recognized. These studies were undertaken to investigate whether Azone, per se, has any activity against herpes simplex (HSV) type 1 and type 2 viruses. When HSV-1 and HSV-2 were mixed with 5, 10 and 20% Azone, there was a 1-4.5 log₁₀ decrease in virus titers. The efficacy of 5 and 10% Azone applied topically was evaluated during the treatment of HSV-1 cutaneous infections in guinea pigs. HSV-1 infection was produced by intradermally inoculating guinea pigs with 10^7.7 HSV-l/ml. The mean number of lesions per site was reduced by more than 50% in Azone-treated sites as compared to no treatment (control) sites (p < 0.01). Similarly, the surface area of each lesion in the Azone-treated sites was only 40% of that seen in control sites (p < 0.001). More than 80% of the lesions on Azone-treated sites healed by day 4 as compared to only 3% on control sites (p < 0.001). These data indicate that Azone, a lipophilic chemical, may have antiviral properties when used topically.