Practical Application of Quality by Design Principles to The Development of an HPLC Assay Method for an API and Impurities

A method for the assay of an active pharmaceutical ingredient (API) and five known and unknown impurities was developed in accordance with Quality by Design (QbD) principles. Highly influential separation parameters were simultaneously and systematically studied so that the quality of the HPLC method could be understood, controlled and ensured. Consequently, during routine analysis out of specification (OOS) results can be corrected more effectively.