Response Surface Methodology as a Tool for Stability-Indicating Method Development and Validation for the Determination of Selective EZH2 Inhibitor

Background: Tazemetostat (TZST) is an efficient first-in-class, selective, EZH2 oral inhibitor which had demonstrated tumor regression and favourable safety in patients with Epithelioid Sarcoma. Methods developed using Analytical Quality by Design (AQbD) are highly robust, cost effective, uses good experimental designs, have shorter run times, optimization can be done by statistical analysis and can be easily validated. Objectives: The objective of the present study was to use the Screening designs for selection of initial chromatographic conditions and Response Surface Methodology (RSM) for development of optimized method based on desirability functions approach and validate sthe developed method as per ICH guidelines. Materials and Methods: To select the column, organic modifier and buffer, a 23 Factorial design was used initially for the experimental plans which majorly affect selectivity. Optimization of the method was done using Central Composite Design (CCD) under RSM Results: Design-Expert software was used for statistical analysis of responses from CCD experimental data using ANOVA and multiple regression analysis. The set of CMP’s which shows a maximum composite desirability was taken as optimized chromatographic conditions and evaluated for the responses. Conclusion: The present work successfully demonstrated the use of AQbD approach for developing and validating stability-indicating RP-HPLC method for determination of TZST