Formulation and Evaluation of Extended-Release Tablets for Calcium Channel Blockers

Abstract

Calcium channel blockers (CCBs) are integral to managing cardiovascular conditions such as hypertension and angina. However, immediate-release (IR) formulations often lead to plasma concentration fluctuations, poor adherence, and adverse effects. Extended-release (ER) tablets address these challenges by ensuring sustained drug release, maintaining steady plasma levels, and reducing dosing frequency. This study focuses on the formulation and evaluation of ER tablets using nifedipine, verapamil, and diltiazem as model drugs. Advanced delivery systems, including hydrophilic matrices and osmotic mechanisms, were employed to achieve controlled release profiles. In vitro dissolution studies demonstrated consistent release rates over 24 hours, transitioning from first-order to zero-order kinetics. Pharmacokinetic evaluations revealed prolonged Tmax, reduced peak-to-trough ratios, and improved bioavailability. Clinical efficacy assessments confirmed superior blood pressure reductions with ER formulations compared to IR counterparts. Stability testing validated long-term potency and physical integrity under accelerated conditions. These findings emphasize the potential of ER formulations to enhance therapeutic outcomes and patient adherence in cardiovascular care.