Development And Validation Of A Stability-Indicating Reversed-Phase Hplc Method For Simultaneous Estimation Of Rosuvastatin And Ezetimibe From Their Combination Dosage Forms

A simple, precise and rapid stability-indicating reversed-phase high performance liquid chromatographic (RP-HPLC) method has been developed and subsequently validated for the simultaneous estimation of Rosuvastatin (RSV) and Ezetimibe (EZE) from their combination drug product. The proposed method is based on the separation of the two drugs in reversed-phase mode using Hypersil C-18 150 x 4.6 mm, 5 mu column maintained at a temperature of 40 degrees C. The optimum mobile phase consisted of 0.05 M phosphate buffer (pH 2.5)-Methanol (45+55, v/v), mobile phase flow rate of 1.0 mL min(-1) and UV detection was set at 242 nm. Rosuvastatin, Ezetimibe and their combination drug product were exposed to thermal, photolytic, hydrolytic and oxidative stress conditions and the stressed samples were analyzed by the proposed method. There were no interfering peaks from excipients, impurities or degradation products due to variable stress conditions and the proposed method is specific for the simultaneous estimation of RSV and EZE in the presence of their degradation products. The method was validated according to ICH guidelines. It was found to be accurate and reproducible. Linearity was obtained in the concentration range of 5-80 mu g mL(-1) for both RSV and EZE with correlation coefficients of 0.99999 and 0.99994 respectively. Mean percent recovery of triplicate samples at each level for both drugs were found in the range of 98% to 102% with RSD of less than 2.0%. The proposed method can be successfully applied in the quality control of bulk manufacturing and pharmaceutical dosage forms.