Stability-Indicating HPLC Method for the Simultaneous Determination of Valsartan and Ezetimibe in Pharmaceuticals

Purpose: To develop a simple, accurate, sensitive, precise and robust reverse-phase HPLC stability- indicating method for the simultaneous estimation of valsartan and ezetimibe in combined tablet formulation.
Methods: A stability indicating method for the simultaneous estimation of valsartan and ezetimibe in combined tablet formulation using a RP-HPLC was developed and validated as per ICH guidelines using a symmetry C18 column with a mobile phase comprising phosphate buffer and acetonitrile (58:42 v/v, pH 3.15) with a flow rate of 0.8 mL/min at 230 nm. Stress degradation studies were performed in acidic, alkaline, oxidation and photolysis conditions to demonstrate the stability-indicating power of the method.
Results: The contents of valsartan and ezetimibe were in the range of 99.77 ± 0.10 and 99.30 ± 0.43 % in the marketed formulation, 99.77 ± 0.08 and 99.29 ± 0.38 for the test formulation, respectively. The correlation coefficient for both valsartan and ezetimibe was 0.999 and recovery was in the range of 98 – 102 %. The limit of detection (LOD) was 0.2 and 0.3 μg/mL for valsartan and ezetimibe, respectively, while limit of quantification (LOQ) was 1 μg/mL for both valsartan and ezetimibe, respectively.
Conclusion: The proposed method is simple, precise, accurate, reproducible, specific and reproducible used for the quantitative determination of valsartan and ezetimibe in bulk and dosage formulations.

Keywords
Valsartan; Ezetimibe; Validation; Stability-indicating; Pharmaceuticals