QBD-Oriented Assay Method Development for the Estimation of Rosiglitazone and Pioglitazone in Bulk and Formulated Dosage Forms

This study presents the Quality by Design (QbD)-driven development and validation of a robust reverse-phase high-performance liquid chromatography (RP-HPLC) method for the simultaneous estimation of Rosiglitazone and Pioglitazone in bulk and pharmaceutical formulations. Employing a Box-Behnken Design (BBD) via Design Expert software, critical method parameters—flow rate, buffer pH, and organic phase ratio were systematically optimized. Statistical validation through ANOVA confirmed the model’s significance, particularly in enhancing resolution and minimizing tailing. The method was validated in accordance with ICH Q2(R1) guidelines, demonstrating excellent system suitability, accuracy (98–102% recovery), precision (%RSD < 2%), linearity (R² > 0.999), sensitivity (acceptable LOD and LOQ), and robustness under varied analytical conditions. The resolution between the two analytes exceeded the threshold of 2, ensuring effective separation. These results affirm the method’s reliability, reproducibility, and suitability for routine quality control of Rosiglitazone and Pioglitazone in pharmaceutical dosage forms.