Biomedical Engineering Reference
In-Depth Information
Figure
2.1. Quality by Design is a systematic approach to development that begins with
predefined objectives and emphasizes product and process understanding and process control
based on sound science and quality risk management (ICH Q8R1). Quality by Design begins by
defining the desired product performance and also by designing a product that meets those
performancerequirements.Thecharacteristicsof thedesignedproductarethebasisfordesigning
the manufacturing process, and the performance of the manufacturing process also needs to be
monitored. Each of these steps may impact each other. For example, process performance may
provideknowledge regardingmanufacturability that could impactproductdesign inan iterative
manner. These steps alsorelate to specificqualitymeasurements and tools. Product specifications
should ideally be basedondesired clinical performance. Theproduct design shouldbe defined in
terms of product quality attributes. The criticality of these attributes and the relationship of
these attributes to specifications may evolve over the product life cycle. Process parameters
are important in defining the process, and process controls are important in ensuring process
performance. This circle of QbD can be split into two general areas, product knowledge and
process understanding. These two areas meet in the design space and the interaction of product
knowledge and process understanding allows for continuous improvement. The QbD circle was
developed by Dr. Moheb Nasr. (See the insert for color representation of this figure.)
quality was given by Dr. Janet Woodcock [13], “Good pharmaceutical quality represents
an acceptably low risk of failing to achieve the desired clinical attributes.” As indicated at
the top of Fig. 2.1, QbD starts with the desired clinical performance.
2.3 RELEVANT PRODUCT ATTRIBUTES
In the draft annex to ICHQ8, ICHQ8(R1) [11], the target product profile is described as a
starting point for Quality by Design. The target product profile is based on the desired
