METHOD DEVELOPMENT AND METHOD VALIDATION FOR TRACE LEVEL QUANTIFICATION OF TWO POTENTIAL GENOTOXIC IMPURITIES IN BAZEDOXIFENE ACETATE DRUG SUBSTANCE BY USING LC-MS (SIR MODE) SELECTIVE ION RECORDING WITH SHORT RUNTIME ANALYSIS

Bazedoxifene acetate represents a promising new treatment for osteoporosis. LC-MS SIR (Selective ion recording) mode, the shortest runtime method, was developed and validated for the trace level quantification of two potential genotoxic impurities, i.e., Impurity-A (1 – Benzyloxy – 4 – nitrobenzene) and Impurity – B (4-benzyloxy-2-bromopropiophenone) in Bazedoxifene acetate drug substance. The concentration limits of both genotoxic impurities were calculated a limit of 75ppm based on the concept of TTC (threshold of toxicological concern) and MDD (maximum daily dosage, which is 20mg/day for Bazedoxifene acetate drug substance). The mobile phase used for the method was 10mM Ammonium acetate and acetonitrile in the ratio of (30:70) v/v with isocratic mode elution at flow rate 0.6mL/min, stationary phase used as X-Bridge C18 (50×4.6) mm, 3.5µm and run time was 5 minutes. The Impurities were quantified by using MS detector SIR mode (Selective ion recording) at m/z of 230.12 and 319.01 for Impurity-A and Impurity-B, respectively. The detection limit (DL) was 1.4 ppm for both Impurity-A and Impurity-B. The quantification limit (QL) for Impurity-A was 3.0ppm, and Impurity-B was 3.1ppm, respectively. The method was found to be linear, from 3.0 ppm to 111.0 ppm for Impurity-A and 3.1 ppm to 112.4 ppm for Impurity-B. The method was found to be Specific, Precise, Linear, and Accurate.