Development and Validation of a Stability-Indicating Reversed-Phase HPLC Method for Simultaneous Estimation of Rosuvastatin and Ezetimibe from Their Combination Dosage Forms

Abstract

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
C18 150 x 4.6 mm, 5µ column maintained at a temperature of 40°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 µg 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.