A Novel Apremilast Nail Lacquer Formulation for the Treatment of Nail Psoriasis.

Abstract

The objective was to prepare a novel nail lacquer formulation to improve the ungual and trans-ungual delivery of apremilast for the potential treatment of nail psoriasis. Nail lacquer formulation was prepared using Eudragit® S 100 as a film-forming polymer and the mixture of ethanol, ethyl acetate, and water as a solvent system. As a result of high-throughput screening studies, dexpanthenol and salicylic acid were found to be the potential penetration enhancers. After 7days of in vitro studies, the cumulative amount of apremilast delivered by the nail lacquer formulation across the nail plate was found to be ~3-fold (0.52±0.07μg/cm2) more compared to control (nail lacquer formulation without enhancers) (0.19±0.02μg/cm2). The cumulative amount of apremilast retained in the nail plate in the case of nail lacquer formulation was 1.26±0.18μg/mg which was found to be ~2-fold more compared to control (0.57±0.07μg/mg). Human subject studies were performed on the nails of thumb and index finger of six volunteers for 15days. As a result, the cumulative amount of apremilast retained in the free distal edge of the nail plate in the case of nail lacquer was found to be ~2-fold (0.93±0.14μg/mg) more related to control (0.41±0.04μg/mg). As a conclusion, nail lacquer formulation was found to be capable of delivering a substantial amount of apremilast into the nail apparatus; thus, it can be a potential option for the treatment of nail psoriasis.