Quantification of Bempedoic Acid and Ezetimibe with Comprehensive Stability Assessment in Drug Substance and Drug Product by UPLC

ABSTRACT: A sensitive and robust UPLC method was developed and validated for the simultaneous analysis of bempedoic acid and ezetimibe in drug substance and drug product. Chromatographic conditions were accomplished using a UPLC (Acquity) CSH C18 column (100 × 2.1 mm, 1.7 μm) under isocratic conditions, utilizing a movable phase comprising of acetonitrile and heptane sulphonic acid buffer (pH 2.5) /OPA in a 5:95 v/v ratio. The absorption wavelength was set at 232 nm, with a flow rate of 0.5 mL/min. International Council for Harmonisation Q2(R1) standards were used for method optimization and included stress studies. The retention times for bempedoic acid and ezetimibe were 0.365 and 1.326 minutes, respectively. The method demonstrated a regression coefficient (R² > 0.999), ruggedness (% RSD < 2%), recovery range (between 98–102%) and robustness. The LOD was 0.54 μg/mL for bempedoic acid and 0.03 μg/mL for ezetimibe. Both compounds exhibited sensitivity to acidic, oxidative, and thermal degradation, confirming the stability-indicating method of the compounds. Overall, the developed UPLC method is precise, accurate, specific, and suitable for quality analysis and stability assessment of bempedoic acid and ezetimibe in both drug substances and drug products.