Formulation Development and Evaluation of Apremilast Nanoemulgel for Enhancing Permeability

Oral apremilast, a selective phosphodiesterase-4 inhibitor, is ef-fective in the treatment of moderate to severe plaque psoriasis and acute pso-riatic arthritic disease. According to BCS categorization, it is a class IV medi-cation, which denotes low solubility and lesser permeability through the skin. The objective of the research is to develop a nanoemulsion that will increase apremilast’s skin permeability. Utilizing a simplex lattice design, an optimised nanoemulsion has been developed, and then transformed into a gel form and created as a nanoemulgel. The nanoemulsion was developed by selecting the oil, surfactant, co-surfactant, and co-solvent, in that order, based on the solubility study, and was then evaluated based on various criteria. Different grades and concentra-tions of carbopol polymer were used to make nanoemulgel, which was then tested for physicochemical parameters like pH, viscosity, spreadability, ex-trudability, percentage of drug content, percentage of drug diffusion, skin permeation, and skin retention. For skin irritancy tests, male Wistar albino rats weighing between 200 and 250 g were used to find out how likely it was that apremilast-loaded nanoemulgel would cause skin irritation. The nanoemulsion formulation A5 containing 10% Captex 355 and 40% Smix in a 3:1 ratio of Cremophore RH 40: Labrafil showed the smallest particle size and greatest drug diffusion. In comparison to other formulations of emulgel, the 0.75 % concentration of carbopol 940 produced the best re-sults. A stable nanoemulgel system with apremilast loaded was creat-ed, and a number of process factors were assessed. The optimised batch pro-duced repeatable results when evaluated, exhibited no skin irritation, and was shown to be stable after three months at ambient conditions of temperature and humidity.