Glossary Definition: Quality by Design (QbD)

Quality by Design (QbD) is an approach to manufacturing that bakes a “quality first” mindset into the planning, development, and manufacturing processes. Its top objective is to ensure that drugs maintain their purity and efficacy from the beginning.

In the words of the late Joseph M Juran, “The quality cannot be tested into the product, but it should be built into it.”

As an engineer and quality evangelist, Juran spent his career teaching about the importance of product quality by design. In pharma, Juran’s teachings became mainstream in 2004 when the FDA began ramping up their efforts to improve the standards of manufacturing.

Quality by Design for pharma is a manufacturing process that improves process understanding. When used correctly, this helps to reduce the likelihood of deviations, and enables better process control strategies throughout every stage of manufacturing.

QbD provides a number of benefits to pharmaceutical manufacturing:

Quality by Design enables scientists, engineers, and manufacturers to catch and analyze issues in real time, helping to minimize discrepancies before they snowball into deviations.

Based on FDA guidelines, there are four main components of QbD. These include:

1. Quality Target Product Profile (QTPP) = Summarizes the quality, safety, and efficacy characteristics of a specific drug that should be achieved. 
2. Critical Quality Attributes (CQAs) = Determines whether or not product quality is within an appropriate limit, range, or distribution to ensure quality. 
3. Critical Process Parameters (CPPs) = Monitors variables and determines if they have an effect on CQAs. 
4. Critical Material Attributes (CMAs) = Outlines input materials and ensures these are within the appropriate limit, range, or distribution.

The purpose of these targets is to plan for quality from the beginning, and then validate it during each stage of production. By pre-planning and determining where quality issues might arise, pharma companies are better equipped to address them as they become a reality.

Quality by Design is important in pharma because it empowers companies to thoroughly prepare for drug production prior to beginning manufacturing. What’s more, as technology continues to advance (like cloud-based, AI-powered MES and LES solutions for pharma), pharma manufacturers can customize their tech stack to adhere to the QbD guidelines.

Through QbD, templated processes can be scaled up or scaled down. They can also be transferred across modalities, so that learnings from one process can be incorporated into another.

Not only does QbD protect consumers by guaranteeing drugs are safe and effective prior to hitting the market, it also benefits manufacturing companies because it reduces failures and costly quality issues.

Lastly, QbD increases speed to market because it allows drug manufacturers to build in quality considerations from the start, instead of finding later in the cycle that they need to make a major change and retest.