ANALYTICAL METHOD DEVELOPEMENT AND VALIDATION FOR THE SIMULTANEOUS ESTIMATION OF ANTIHYPERLIPIDEMIC COMBINATION BY RP-HPLC METHOD

A simple, rapid, economical, and precise reverse-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for the simultaneous estimation of Bempedoic acid and Ezetimibe in bulk drug and combined tablet dosage form. Chromatographic separation was achieved using a Kromosil C18 (150 × 4.6 mm, 3.0 µm) column with an isocratic mobile phase consisting of 0.01 N potassium dihydrogen phosphate (KH₂PO₄) buffer and methanol in the ratio of 80:20 v/v, delivered at a flow rate of 0.9 mL/min. The column was maintained at 30 °C, and detection was performed at 229 nm. The retention times of Bempedoic acid and Ezetimibe were found to be 2.132 min and 2.586 min, respectively, indicating a short run time of less than 3 minutes. The method exhibited excellent linearity over the concentration ranges of 22.5–135 µg/mL for Bempedoic acid and 1.25–7.5 µg/mL for Ezetimibe, with correlation coefficients (R²) of 0.9999 for both analytes. Accuracy studies showed mean recoveries of 100.00% for Bempedoic acid and 100.14% for Ezetimibe. Precision, robustness, specificity, and sensitivity parameters complied with ICH Q2(R1) guidelines. LOD/LOQ values were 1.01/3.38 µg/mL for Bempedoic acid and 0.02/0.05 µg/mL for Ezetimibe. Forced degradation studies under acid, base, oxidative, thermal, UV, and water stress conditions confirmed the stability-indicating nature of the method. Overall, the proposed RP-HPLC method is accurate, reliable, reproducible, and suitable for routine quality-control analysis of combined Bempedoic acid and Ezetimibe formulations.