The document discusses Quality by Design (QbD), which is a systematic approach to pharmaceutical development that begins with predefined objectives and emphasizes product and process understanding based on sound science and quality risk management. QbD involves determining critical quality attributes, understanding how raw materials and process parameters affect those attributes, developing a design space and control strategy to manage the product lifecycle. Design of experiments is a key QbD tool that involves screening factors, response surface methodology, formulation evaluation, computer modeling and validation to optimize the process and enable scale up.

2. • A systematic method relating mechanistic understanding of input
material attributes and process parameters to drug product critical
quality attributes.
• Accomplished through the use of multivariate experiments involving
modern process controls enabling process understanding.
• QbD-based pharmaceutical manufacturing process will be
adjustable within a design space, providing a robust process that is
managed with a control strategy developed using modern statistical
process control methods.

3. 1. The International Conference on Harmonization (ICH) has
defined QbD in ICH Q8R as:
2. “ A systematic approach to pharmaceutical development that
begins with predefined objectives and emphasizes product and
process understanding based on sound science and quality risk
management”.

6.  Quality Target Product Profile.
 Determine critical quality attributes (CQAs).
 Risk assessment: Link raw material attributes and process parameters
to CQAs.
 Develop a design space. (optional not required)
 Design and implement a control strategy.
 Manage product lifecycle, including continual improvement.

7. QUALITY BY DESIGN (QbD) TOOLS:
DESIGN OF EXPERIMENT:
• Defining objectives of the study and planning the experiment.
• Screening of factors and factor influencing study.
• Response surface methodology.
• Formulation and evaluation of DDS.
• Computer aided modelling and search for an optimum.
• Validation of DOE methodology.
• Scale up and implementation.

8. • The input variables, which are directly under the control of the product
development scientist, are known as Independent variables e.g., drug
content, polymer composition, compression force, percentage of
penetration enhancer, hydration volume, agitation speed.
- QUANTITATIVES VARIBLES.
- QUALITATIVE VARIABLES.
• The characteristics of the finished drug products or in process material are
known as DEPENDENT VARIABLES. E.g., drug release profile, percentage
drug entrapment, pellet size distribution, moisture uptake.