IN VITRO SKIN ABSORPTION AND DRUG RELEASE – A COMPARISON OF SIX COMMERCIAL PREDNICARBATE PREPARATIONS FOR TOPICAL USE.

This study by researchers at the Freie Universitat Berlin and Charite–Universitatsmedizin Berlin demonstrated that MatTek’s EpiDerm in vitro human skin tissue equivalent is an excellent in vitro model to study the potential skin metabolism of drugs designed to be applied to and/or penetrate human skin. Reconstructed human epidermis is a useful tool for in vitro skin absorption studies of chemical compounds. To see if this is also true for topical dermatics, researchers at the Freie Universitat Berlin and Charite–Universitatsmedizin Berlin investigated the glucocorticoid prednicarbate applied by two sets (innovator and generic) of cream, ointment and fatty ointment using the commercially available EpiDerm™ in vitro human skin tissue model. Stability and local tolerability of the preparations as well as drug release were studied in order to estimate the influence on prednicarbate absorption and metabolism. While release ranked in the order cream < fatty ointment < ointment for both sets of preparations, prednicarbate penetration and permeation of the EpiDerm model did not. Less prednicarbate uptake observed with the generic ointment and fatty ointment appeared to be linked to impaired enzymatic ester cleavage within the tissue. Thus with drugs subject to skin metabolism, cutaneous uptake is not to be derived from drug release studies, yet has to be studied experimentally with viable skin or reconstructed human epidermis.

Adenylate kinase (AK) activity, Cream, Drug metabolism, EPI-200-X-HCF, EPI-606-X, Enzymatic ester cleavage, EpiDerm, Fatty ointment, Glucocorticoid, IL-1a, MTT, Metabolism, Ointment, Skin metabolism

Dermatop® cream, Prednicarbate, Prednitop® cream