A Stability-Indicating HPLC Method for the Determination of Bazedoxifene Acetate and its Related Substances in Active Pharmaceutical Ingredient

A simple, cost effective, stability-indicating reversed-phase high-performance liquid chromatography method was developed for the quantitative determination of bazedoxifene acetate (BAZ) drug substance in the presence of its impurities and degradation products. The method was developed using an X-terra RP-18, 150 x 4.6 mm, 3.5 mu m column with a mobile phase containing solvent A, a mixture of 10 mM K2HPO4 (pH 8.3) and acetonitrile in the ratio of 70:30 (v/v); and solvent B, a mixture of water and acetonitrile in the ratio 10:90 (v/v). The eluted compounds were monitored at 220 nm, and within a short run time of 18 min, BAZ and its impurities were satisfactorily separated with resolution more than 2.0. BAZ was subjected to stress degradation and found to be sensitive towards acidic, basic, oxidative, thermal and hydrolytic stress conditions and stable in photo degradation conditions. The degradation products were well resolved from BAZ peak and its impurities; the mass balance in each case was more than 99.5%, proving the stability-indicating power of the method. The developed method was validated as per International Conference on Harmonization guidelines with respect to specificity, linearity (correlation coefficient > 0.9994), limit of detection, limit of quantification, accuracy (recovery range 96.3 to 102.1%), precision (relative standard deviation < 2.8%) and robustness.