QUALITY BY DESIGN - Risk Management Applications in Pharmaceutical and Biopharmaceutical Manufacturing - page 88

5.2 DEVELOPMENT OF PRODUCTS USING A QBD APPROACH

There are several stages in developing a new product using a QbD methodology.
These stages are applicable in principle whether the products are small or large
molecules.
The principle steps based on Q8R2 start with patient safety and efficacy
requirements, to ensure the final drug product meets quality requirements. In
order to explain the QbD approach, it uses the following terms:
• quality target product profile (QTPP);
• critical quality attribute (CQA);
• risk assessment: linking process parameters and material attributes to drug
product CQA;
• design space;
• control strategy;
• product life cycle management and continual improvement.
These are diagrammatically shown in Figure 5.1. It should be noted that
although the flow goes broadly from left to right, there can be many iterations
on the way.
The key output of this flow is to develop and put in place a control strategy to
assure product quality and to meet patient safety and efficacy requirements over
the life cycle of the product.
Risk assessment is a key part of this overall process and is normally carried
out at each stage, to ensure, as knowledge is gained, that potential risks are
understood, mitigated, and controlled.
ICH Q9 provides the basis for risk management and uses the following diagram
as guidance (Fig. 5.2).

Progress along these steps is normally an iterative process

Quality
target
product
profile
(QTPP)

Critical
quality
attributes
(CQA)

Critical
process
parameter
(CPP)

Continual
improve
ment

Design
space

Control
strategy

Figure 5.1 Diagrammatic flow of key steps for QbD. ( See insert for color representation
of the figure .)