Beyond SOPs – Exploring the rigor and requirements of Analytical QbD
Analytical QbD (AQbD) promises to extend the rigor and benefits of QbD into the area of analytical method development. Here, Paul Kippax provides an introduction to the methodology involved and takes as an example the application of AQbD to the development of a laser diffraction particle sizing method.
The application of Quality by Design (QbD) has become second nature to the pharmaceutical industry. The concept of scoping, understanding and controlling a pharmaceutical manufacturing process within the 'design space' is well-established. Alongside this, Process Analytical Technology, most especially on-line measurement, is recognised as playing an important role in delivering the information and understanding to drive QbD, at the pilot scale and through into manufacture.
The FDA have encouraged the adoption of QbD by offering, in return, operational freedom within the design space. This enables a responsive approach to understood but unavoidable variability and can substantially enhance manufacturing efficiency. Such gains prompt the question as to whether the principles enshrined in QbD are applicable to other processes, and analytical method development is now a focus. Just like conventional QbD, analytical QbD (AQbD) holds out the prize of flexibility, in contrast to the rigidity of Standard Operating Procedures (SOPs).