Release of miconazole from topical PVA matrices: preliminary in vitro and in vivo data

Abstract

The present paper is concerned with a preliminary evaluation of cutaneous polymeric matrices containing an antimycotic drug, miconazole. A series of poly (vinyl alcohols), PVA, with differing molecular weight and degree of hydrolysis, and one PVA copolymer internally plasticised were chosen as matrix-forming materials. Miconazole-containing matrices (200, 400 and 1300 μmg/matrix) were prepared by casting, and evaluated in vitro for water vapour transmission, drug release and antifungal activity on Candida albicans. On the basis of their in vitro performance, four polymers were submitted to in vivo skin release tests, in which the matrices (1300 μg) were either applied as such to the skin, or were formed in situ by evaporation of a solution containing the polymer and the drug. A more efficient release, observed for all in situ matrices with respect to the pre-formed ones, was attributed to the better adhesion and penetration of the polymeric material in the epidermal surface. One of the polymers, a PVA with a high degree of hydrolysis, showed the best release characteristics in vivo. The relevance of the in vitro to the in vivo tests, as well as the potential advantages of topical PVA matrices as carriers for antifungal and antimicrobial drugs, are discussed.