Preparation and Evaluation of Solid Dispersion-Based Bilastine Effervescent Granules

Abstract

Background: Bilastine (BLA) is a second-generation H1 antihistamine used to treat allergic rhinoconjunctivitis. Because of its limited solubility, it falls under class II of the Biopharmaceutics Classification System (BSC). The solid dispersion (SD) approach significantly improves the solubility and dissolution rate of insoluble medicines. Objective: To improve BLA solubility and dissolution rate by formulating a solid dispersion in the form of effervescent granules. Methods: To create BLA SDs, polyvinylpyrrolidone (PVP K30) and poloxamer 188 (PLX188) were mixed in various ratios (1:5, 1:10, and 1:15) using the kneading technique. All formulations were evaluated based on percent yield, drug content, and saturation solubility. The formulae with the greatest solubility enhancement were subjected to in vitro dissolution studies, Fourier transform infrared, and thermal analysis to study drug crystallinity and drug-polymer interactions. The best SD formula was made as effervescent granules using wet granulation and tested further. Results: The SD3 formula, which contained PVP K30 in a 1:15 ratio, had the highest solubility and release. In phosphate buffer (pH 6.8), over 88.43% of the BLA was released within the first 15 minutes. The optimum formula's effervescent granules demonstrated excellent flow qualities, a disintegration time of 87 seconds, an acceptable pH of 5.9, and 9.7 mg of BLA dissolved in the first 5 minutes. Conclusions: BLA dissolution can be improved via the solid dispersion technique, allowing for successful effervescent granule formulation.