Abstract
Tazarotene, a member of a novel class of synthetic acetylenic retinoids, is the first topical retinoid to demonstrate both efficacy and an acceptable patient tolerability profile in the treatment of psoriasis. The subchronic and chronic toxicity of topically applied tazarotene gel (0.025-0.1%; 0.05-0.5 mg/kg/d) was evaluated in Hanford miniswine in two separate, prospective, randomized, vehicle-controlled studies of 3 months' and 12 months' duration. Although tazarotenic acid, the active metabolite of tazarotene, was detected in the blood of animals in both studies, no signs of systemic toxicity could be detected in hematology, blood chemistry, posttreatment physical examination, necropsy, or histopathological examination of organ tissues. In both studies, the reversible signs and symptoms of cutaneous irritation caused by topical application of tazarotene gel were consistent with those effects commonly produced by other topical and oral retinoids.