QbD Approach to Process Characterization and Quantitative Criticality Assessment of Process Parameters

The quality-by-design (QbD) approach is widely utilized for developing and validating manufacturing processes for drug substances as well as drug products. This paper discusses the application of the risk-based QbD approach used at F. Hoffmann-La Roche Ltd. for development, optimization, and characterization of drug substance manufacturing processes for small molecules. It presents the evolution of the QbD concept into statistical thinking and development of a quantitative tool, namely, the impact ratio concept, for its successful implementation. The utilization of this approach is illustrated with a case study from the taselisib drug substance manufacturing process.