Formulation and In-Vitro Evaluation of Celecoxib Sustained Release Tablets Using Hydrophilic and Hydrophobic Polymer Matrices

Abstract

Background: Celecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor widely prescribed for management of osteoarthritis, rheumatoid arthritis, and acute pain. Its short biological half-life and poor aqueous solubility (BCS Class II) necessitate frequent dosing, which compromises patient compliance. Objective: This study aimed to formulate sustained-release (SR) tablets of celecoxib using hydrophilic (HPMC K4M, HPMC K15M, Carbopol 934P) and hydrophobic (ethyl cellulose) polymers by direct compression and evaluate them through comprehensive physicochemical and in vitro dissolution testing. Methods: Six formulations (F1–F6) were prepared at varying polymer concentrations. Pre- and post-compression parameters were assessed per Indian Pharmacopoeia (IP) and USP standards. Dissolution was studied in phosphate buffer pH 6.8 over 12 hours using USP Apparatus II. Release kinetics were modelled using zero-order, first-order, Higuchi,and Korsmeyer-Peppas models. Results: All formulations exhibited acceptable hardness (7.8–8.5 kg/cm²), friability (<1%), and drug content 97.6–99.1%). Formulation F6 (Carbopol 934P) demonstrated optimum cumulative drug release of 75.4% at 12 hours with best kinetic fit to the Korsmeyer-Peppas model (R² = 0.996, n = 0.728), indicating non-Fickian anomalous diffusion. Conclusion: Celecoxib SR tablets with satisfactory physicochemical characteristics and sustained drug release suitable for twice-daily dosing were successfully formulated using Carbopol 934P as the matrix polymer.