The development of in vitro release methodology for high strength topical semisolid formulations of anti-inflammatory drugs

The strict requirements applicable for the development of the in vitro methodologies able to assess the performance of topical semisolid dosage forms make difficult the selection of testing parameters and conditions for high strength, low consistency, and fast releasing formulation. The article presents the development of an in vitro release test adapted to the particularities of ibuprofen 10% solution-type gels. The results, analysed by currently recommended approaches as available in the regulatory guidance documents, indicated that both strength and microstructural discrimination could be difficult to achieve and requires higher degree of non-similarity between target formulation and those altered by controlled changes.