Tazarotene Foam versus Tazarotene Gel: A Randomized Relative Bioavailability Study in Acne Vulgaris

Abstract

Tazarotene, a retinoid pro-drug, is available in gel, cream and foam for the topical treatment of acne vulgaris. This single-centre, randomized, open-label study assessed relative bioavailability of its active metabolite tazarotenic acid after dosing of tazarotene foam or gel. Subjects with moderate-to-severe acne received a mean, once-daily dose of 3.7 g tazarotene foam or gel applied to face, chest, upper back and shoulders. Blood samples were collected pre-dose on multiple days and multiple time points over a 72-h period to measure plasma tazarotenic acid and tazarotene. Mean tazarotenic acid area under the plasma concentration-time curve (AUC) and maximum measured plasma concentration (Cmax) values were significantly higher for gel versus foam. Cmax occurred within 5-6 h after dosing, with an apparent terminal elimination half-life (t½) of 18-22 h. Accumulation was observed upon repeated dosing with steady-state conditions achieved at day 20. Mean tazarotene concentrations were also higher following gel application versus foam. Both foam and gel demonstrated an acceptable safety profile. Tazarotene foam, 0.1 % is an alternative to gel with less systemic exposure.