Biomedical Engineering Reference
In-Depth Information
Figure
13.2. The QbD approach (from ICH Q8R1).
“key” or “nonkey” if they impact process performance (e.g., yield) without impacting
quality, or if they have no impact on either in the range studied.
The linkage between inputs and quality attributes is described in the design space,
which is a multidimensional description of the conditions (input variables and process
parameters), which result in a product with the desired CQAs being produced. It can be
based on a unit operation or the overall process. Design space can be defined in scale and
equipment independent terms, which can facilitate technology transfers between scales
or even sites as the project or commercial process matures.
The next step is to design and implement a control strategy. Here is where PAT
plays amajor role, and it can be used independently or together with additional strategies,
including end-product testing. PAT approaches often require continuous or at least
