Gastroretentive microballoons of olmesartan medoxomil: formulation and <i>in vitro-in vivo</i> evaluation

Olmesartan medoxomil, classified as BCS class II due to its poor water solubility, exhibits a low oral bioavailability of 28.6%. Microballoons of Olmesartan medoxomil were formulated using the ionotropic gelation technique and subjected to various evaluation parameters. The particles were found to be in the range of 85.11 to 312.6 µm. The prepared microballoons remained buSSoyant for more than 12 hours and showed percentage of cumulative drug release between 56.32–83.62%. <i>In vivo</i> studies showed significant reduction in Systolic blood pressure (SBP) in optimized formulation (OF). The formulated microballoons (hollow microspheres) emerged as a promising option for an oral gastro retentive controlled drug delivery system for Olmesartan medoxomil. Floating microballoons were formulated, optimized, and assessed to achieve improved bioavailability along with sustained release characteristics.奥美沙坦酯（Olmesartan medoxomil）因水溶性极差，被归类为生物药剂学分类系统（Biopharmaceutics Classification System, BCS）II类药物，其口服生物利用度仅为28.6%。采用离子凝胶法制备奥美沙坦酯微球囊，并对其多项评价参数进行考察。所得微粒粒径分布于85.11~312.6 μm之间。所制备的微球囊可保持漂浮状态超过12小时，药物累积释放率介于56.32%~83.62%之间。体内（in vivo）研究结果显示，优化处方（optimized formulation, OF）可显著降低收缩压（Systolic blood pressure, SBP）。所制备的微球囊（即空心微球）是奥美沙坦酯口服胃滞留控释给药系统的一种极具潜力的候选方案。漂浮型微球囊的制备、优化与评价工作，旨在实现药物生物利用度的提升及缓释释药特性的达成。