Development and validation of RP-HPLC method for simultaneous estimation of Sofosbuvir and Velpatasvir and in tablets using Quality by Design approach

In present work, a simple, accurate and precise RP-HPLC method was developed and validated for simultaneous estimation of Sofosbuvir and Velpatasvir in tablets. A systematic Quality by Design (QbD) approach was employed to optimize the chromatographic parameters, using rotatable central composite design for multivariate analysis. The method’s critical parameters, including acetonitrile percentage, flow rate and column temperature were optimized to achieve acceptable resolution and system suitability with enhanced accuracy and precision. The quadratic models obtained for each response, enabling a detailed understanding of the factors influencing method performance. The ANOVA confirmed the significance of the models and the adequacy of the equations, with flow rate and organic phase concentration being the most critical factors affecting retention time and resolution. The method was validated in accordance with ICH guidelines, demonstrating good linearity, accuracy, precision, sensitivity and specificity of sofosbuvir and velptasvir. The method’s robustness, combined with its validated accuracy and precision, makes it suitable for routine quality control analysis in pharmaceutical formulations.