Building Blocks of Quality by Design | IVT
This is the first of a monthly series of short commentaries on the use of Quality by Design (QbD) in the pharma and biotech industries. The use of QbD has steadily grown since its introduction around 2005. The growth has not been fast enough for some and perhaps too fast for others. Some of the resistance is due to lack of understanding what QbD is. This is not uncommon for a new idea. QbD is new to pharma and biotech but not new to other industries. This is good news as pharma and biotech can learn from the experience of others. The breadth of application and understanding of QbD has grown since it was first introduced mainly in the chemical industry in the 1950s and 1960s. I learned about QbD in my graduate work at Rutgers University and practiced and enhanced the art and science, first during by 24 year tenure at DuPont and today as a keen focus of my consulting practice and research programs.
It is important to begin these commentaries by answering the question 'What is QbD'; and then discuss the building blocks of QbD. The ICH Q8 (R2) definition is that QbD is a "Systematic approach to product and process development that begins with predefined objectives, emphasizes product and process understanding and process control and is based on sound science and quality risk management (1)." In other words, Quality by Design is about building quality into products and processes, not attempting to inspect quality in at the end on the line.
This definition leads us to the "building blocks" of QbD needed to provide the process and product understanding that is fundamental to the ICH definition of QbD stated above and its effective use (2).
The principle building blocks of QbD are:
These building blocks should not be viewed a list of "to dos" but each as a block of work that is linked together and sequenced over time as shown in the following figure in which the word "process" is used to represent both the manufacturing process and the measurement process. This figure points out an important characteristic of QbD, the sequential nature of the approach. QbD is implemented over time not as a single event. The building blocks are linked together to produce the process understanding needed to get the product approved and launched successfully with the desired performance sustained throughout the product lifecycle.
It is in reduced risk that all of these critical elements converge. As football Hall of Fame quarterback Johnny Unitas said, "There is no risk of an intercepted pass, if you know what you are doing." QbD provides the process understanding that enables you to know what you are doing, resulting in greatly reduced risk.
QbD is generally viewed as an activity of product and process development. Next month I will discuss how QbD is also useful in improving existing processes and products. Instead of incrementally improving unit operations that, in isolation, may have little effect on overall process performance or quality, manufacturers can adopt a holistic approach to QbD that is applicable at every stage of the product lifecycle (4). When combined with sound deployment methodologies, improvement management systems, and appropriated infrastructure, QbD dispels misconceptions with the most convincing corrective of all – a sustainable, significant increase in value (5).
I'm very much interested in receiving your comments and questions regarding QbD. Your input will be very useful in identifying future commentaries.
This article was originally published in IVT - Read article on IVT