It is well-known that individuals can vary widely in their responses to the same medication. A treatment that has been shown to be safe and effective in a particular population may have no effect—or can cause adverse effects—in certain individuals or subpopulations. Biologic variability in drug response can be linked to numerous, sometimes overlapping factors, including genetic differences, factors such as race, age, and sex, and environmental and/or behavioral factors such as alcohol use, climate, and diet.
Accurately predicting and addressing the effects of biologic variability during drug development is a source of growing concern for researchers, drug sponsors, and regulators. These challenges include insufficient understanding of the sources of biologic variability, underrepresentation of certain demographic groups (such as women and minorities) in some clinical trials, and the challenges of designing and conducting clinical trials that are able to capture meaningful data on that variability. Achieving a better understanding of how and when biologic variability happens—as well as when the effect of that variability on patients is clinically significant—is necessary to ensure public health and safety and to improve clinical outcomes.