Quality by Design (QbD): A Practical Experimental Design Approach by Blocking and Varying Certain Factors of a Stability-Indicating HPLC Method for Simultaneous Determination of Omeprazole and Ketoprofen.

This manuscript demonstrates a Quality by Design approach using Design of Experiments to prove the robustness of a stability indicating HPLC method. The method determines the omeprazole in the presence of eight related substances and ketoprofen with six impurities developed for pellets filled capsule as a combined finished drug product. Based on the results, controllable factors that have influential effect on the resolution between peaks were identified and were examined while blocking the uncontrollable factors. The design employs a full factorial design of experiment for the interaction of controllable factors. A flowchart parades all steps of QbD approach by blocking and varying certain factors. Thus, the primary objective of this manuscript is to demonstrate the method's robustness by clarifying various steps systematically. [ABSTRACT FROM AUTHOR]