EDITOR’S NOTE: This article is part of a series of highly popular blog posts that we are republishing to share their important topics with a wider audience and with those who may be new to GxP Lifeline.
It seems that Quality by Test is well on its way to being a thing of the past, and for good reason. With only one out of every 10 drug products actually making it to market(1), it is no surprise that pharma companies are increasingly eager to adopt measures to ensure quality and manage risk. Quality by Design (QbD) continues to be a hot topic across the life sciences industries, and as evidenced by the widespread adoption of QbD among manufacturers, there is no question about its benefits.
“The main issue with late-stage quality analysis is that it only detects and removes substandard products – it doesn’t prevent them from being created in the first place,” said a PharmTech article on the topic of pharmaceutical QbD(2). “As pharmaceuticals become increasingly complex, it’s more important than ever that quality is designed into the products from the initial concept to ensure patient safety.”
With adoption of pharmaceutical QbD on the rise throughout the pharma sector, regulatory bodies such as the U.S. Food and Drug Administration (FDA) work to further develop a common understanding of key concepts, terminology and expectations.
Establishing a definition of pharmaceutical quality is really the first step to incorporating QbD into the design and development of drug products, and as with most industry terms, it can be challenging to reach a consensus.
In general, quality can be defined as products that meet scientifically derived product and process performance objectives, while exhibiting minimal variation within each batch and from one batch to another(3). Specific to pharma, ICH Q8 (R2) defines quality as the suitability of either a drug substance or drug product for its intended use(4). Janet Woodcock, the director of the Center for Drug Evaluation and Research (CDER), offers a similar yet nuanced definition: a high-quality drug product as one that is free of contamination and reliably delivering the therapeutic benefit promised in the label to the consumer(5).
Unlike the empirical-based methods used in traditional product development and manufacturing methods, QbD is a scientific, risk-based approach that focuses on designing quality into a product from the earliest stages of planning to prevent quality failures from ever occurring, and more readily address them if they do occur(6). Many companies practice different interpretations and variations of QbD(7), but most can agree that it comes down to fully understanding and controlling all aspects of the manufacturing process as they pertain to the critical quality attributes of a drug product, collectively known as the design space(4). In addition to achieving a safer and more effective product, QbD affords greater regulatory flexibility with respect to the design space, all of which translate into direct cost benefits for producers.
What these definitions have in common is a focus on achieving a reliably safe and effective end product to deliver better patient outcomes, providing obvious benefits to both consumers and pharma companies alike. Thus, the question drugmakers are asking about QbD is not so much why, but how.
To bridge the gap between theory and practice, ICH Q8 (R2) along with other research initiatives(8) have given us a solid starting point for implementing pharmaceutical QbD. Below are the key elements of a QbD program(9):
Because pharmaceutical QbD requires considerable resources (time, money, personnel, expertise, etc.) to implement, it gained momentum initially among larger pharma companies(10). But QbD is now on the rise among forward-thinking companies of all sizes, particularly as the required knowledge, technology and tools become more established and widely available.
However, despite the efforts she and others have already made to advance our understanding of pharmaceutical quality, Woodcock believes there is still work to be done when it comes to manufacturing quality, an equally critical element of QbD.
“Actually, we defined the quality of a pharmaceutical product a long time ago: fitness for use,” Woodcock stated in a Pharmaceutical Online article(11). “It delivers the properties described on the label and is not contaminated. But the other piece is, what is quality in manufacturing? And that’s really what we are focusing on.”
She continued, “Right now, a lot of the industry delivers quality products by throwing away, by wasting, up to 35 percent of what’s produced, and we don’t believe that amounts to quality manufacturing. We’ve been exploring this question extensively with industry in a very open process: ‘What metrics might we use that would measure the quality of your manufacturing processes?’”
What we do know is that the FDA, the European Medicines Agency (EMA) and other key regulatory authorities support a risk-based approach to and the inclusion of QbD principles in the development and production of drug products. The latest ICH Quality Guidelines Q8 to Q11 also address different aspects of QbD as they apply to the pharma industry. So while some questions may remain, QbD is clearly here to stay.
References
1. The High Price of Failed Clinical Trials: Time to Rethink The Model. 2016. Clinical Leader.
2. QbD: Improving Pharmaceutical Development and Manufacturing Workflows to Deliver Better Patient Outcomes. 2017. Pharmaceutical Technology.
3. Quality by Design Part 1: You Can’t Design Something You Don’t Understand. 2016. GxP Lifeline.
4. ICH Q8 (R2) Pharmaceutical Development. 2009. International Council for Harmonisation.
5. The Concept of Pharmaceutical Quality. 2004. American Pharmaceutical Review.
6. Juran’s Quality Handbook. 1999. McGraw Hill.
7. Active Pharmaceutical Ingredients: Development, Manufacturing, and Regulation. 2009. CRC Press.
8. Report From the EMA-FDA QbD Pilot Program. 2017. European Medicines Agency and U.S. Food and Drug Administration.
9. Understanding Pharmaceutical Quality by Design. 2014. AAPS Journal.
10. Is Quality by Design Just for Big Pharma? 2012. GxP Lifeline.
11. Janet Woodcock’s Quality Agenda at CDER. 2014. Pharmaceutical Online.