DOI: https://doi.org/10.36347/sajp.2026.v15i08.002

Pages: 179-194

This study aimed to develop and validate an in vitro release test (IVRT) method for a gel formulation containing a glycosaminoglycan-derived active pharmaceutical ingredient (API) using Franz diffusion cells, in accordance with ICH Q2(R2), the FDA guidance “In Vitro Release Test Studies for Topical Drug Products Submitted in ANDAs” and USP <1724>. Two receptor media, pH 7.4 phosphate buffer and pH 7.4 phosphate buffer containing 20% ethanol, and two membrane types, 0.45 µm cellulose acetate (CA) and a 300 kDa dialysis membrane, were comparatively evaluated for their impact on API release. Quantitative analysis of the released API was performed by HPLC using a USP L81 column and an ionic mobile phase, with UV/PDA detection. Optimal IVRT conditions for both test and reference products were established at 400 rpm using the 300 kDa dialysis membrane in pH 7.4 phosphate buffer, with sampling at 0.5, 1, 2, 3, 4 and 5 hours. The cumulative release profiles were statistically compared using the Mann-Whitney U test, demonstrating no significant difference between the test and reference products. In conclusion, the validated IVRT procedure provides a robust, discriminatory and regulatory-compliant analytical tool for the quality control and in vitro sameness (in vitro equivalence) evaluation of gel formulations containing a glycosaminoglycan-derived API.