Setting meaningful and realistic specifications is an essential element of Quality by Design (QbD). Well-defined specifications control product performance since they derive from correlations between clinical behaviour and the variables measured routinely during processing and for QC. This paper examines the process of setting specifications, taking as an example particle size, a critically important parameter for many pharmaceutical formulations.
Multiple pressures on the pharmaceutical industry and the regulatory bodies that control it are driving the shift towards a risk-based approach to production. Increasingly regulators are focusing scarce resource on those less well-understood products and processes with significant potential for harm, responding more flexibly to manufacturers who can demonstrate sound understanding and control. Quality by Design (QbD) is a key part of this change in emphasis, promoting development of the knowledge through which manufacturers will prove competence.