In pharmaceutical manufacturing, it is not enough to simply demonstrate that a particular set of production parameters results in a safe and effective product; it is far more useful to demonstrate the boundaries for each parameter within which quality objectives can be achieved.
Why? If companies can demonstrate to regulators that the items they produce meet specifications within a wider range of production settings, they then have the flexibility to vary a production process as needed across those settings.
Quality by design is an approach that allows manufacturers to identify and evaluate all sources of variability with respect to quality parameters of the finished product. This paper uses a case study to demonstrate that quality by design goals can be derived in a straightforward way and that this method allows for further improvement of the process without the need for re-registration.