Double-blind, randomized, placebo-controlled study of topical 5% acyclovir-1% hydrocortisone cream (ME-609) for treatment of UV radiation-induced herpes labialis

Abstract

Immunopathology is recognized as an important component of infectious disease manifestations, and corticosteroids have been used as an adjunct to antimicrobial therapy for a variety of conditions. Antiviral therapy of herpes labialis has been shown to result in only a small reduction in the time to healing and the duration of pain. To determine if topical application of a combination product containing 5% acyclovir and 1% hydrocortisone (ME-609) could provide benefit to herpes labialis patients, 380 immunocompetent adults with a history of herpes labialis were exposed to experimental UV radiation (UVR) to induce a recurrence. On day 2, just before the appearance of the majority of lesions ("delayed" lesions), subjects were randomized to receive active medication or vehicle control six times per day for 5 days. Overall, 120 of 380 patients developed delayed classical lesions, of whom 50 of 190 (26%) had been treated with ME-609 and 70 of 190 (37%) had received placebo (a reduction of 29% [P = 0.02]). Healing time, measured as the time to normal skin, was reduced by treatment with ME-609 (9.0 days for treated patients versus 10.1 days for the controls [P = 0.04]). There was a trend toward a reduction in the maximum lesion size in the ME-609 recipients compared to that in the controls (43 versus 60 mm(2), respectively [P = 0.07]). The treatment had no effect on lesion pain, but ME-609 treatment reduced the number of patients with moderate or severe tenderness. Compared to treatment with a placebo, treatment with the combination antiviral-immunomodulatory cream provided benefit to patients with experimental UVR-induced herpes labialis, reducing classical lesion incidence, healing time, lesion size, and lesion tenderness. ME-609 is a novel product that merits further evaluation as a treatment for cold sores.

FIG. 1.

Start of lesions shown as time from UVR exposure in patients developing classical lesions, per treatment group. Day zero includes the first 24 h following UVR exposure. □, ME-609; ▪, placebo.

FIG. 2.

The Kaplan-Meier curve (ITT population) for time to normal skin in patients with delayed classical lesions, per treatment group. Cum. prop., cumulative proportion; thick line, ME-609; thin line, placebo.

FIG. 3.

Median durations of lesion stages in patients (ITT population) with delayed classical lesions. The papule stage (▪) is the time from the start of a lesion (papule) to the time of observation of the first vesicle. The vesicle stage () is the time of observation of the first vesicle to the time of the first sign of crusting. The crusting stage (░⃞) is the time from the first sign of crusting to the time of the loss of the hard crust. The healing stage (□) is the time from the loss of the hard crust to normal skin.