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FDA and Personalized Medicine
Consistent with its core mission, the FDA’s is working in collaboration with research-
ers, drug manufacturers, medical devices and biologics, health care professionals and
others to better understand and adapt to the promise of personalized medicine ( http://
http://www.fda.gov/scienceresearch/specialtopics/personalizedmedicine/default.htm ).
The FDA provides guidance on a broad range of topics, such as incorporating
genetic and other biomarker information in drug development programs, designing
clinical trials to incorporate biomarker data, coordinating cross-labeling activities,
evaluating pharmacogenomics data, and demonstrating companion diagnostic test
performance. FDA’s ongoing efforts to make personalized medicine possible touch
on various facets of product development and use including:
- Early stage development
- Regulatory pathways and policies
- Product use
Regulatory Aspects of Pharmacogenetics
The attitude of various regulatory agencies to pharmacogenetics has so far been not
been well defi ned. New regulatory challenges will surface with the development of
drugs targeted at special populations. There are no regulatory requirements for
pharmacogenetic data. Current guidelines of the European Medicines Evaluation
Agency do not specifi cally mention pharmacogenetics but they recommend the
value of a “population approach” to clinical trials to screen for drug interactions.
The FDA is starting to formulate a policy on pharmacogenomic studies.
FDA currently views genetic variations as one of the many factors that contribute
to drug response and a 1999 document by the FDA on drug metabolism/interactions
in vitro refers to use of pharmacogenetic data in determining drug dosage: “In vivo
drug metabolism/drug interaction studies” ( http://www.fda.gov/cber/guidelines.htm ). One
example quoted in this draft is that if in vitro studies indicate that CYP2D6 or 3A4
enzyme systems do not metabolize an investigational drug, then clinical studies to
establish this effect are not necessary. The FDA occasionally has used early pharma-
cogenomics information on a drug’s label. For example, the drug Straterra, for atten-
tion defi cit and hyperactivity disorder, contains information that people with a
variation of the 2D6 drug-metabolizing enzyme process the drug more slowly and
thus are more prone to side effects. Some children with leukemia have an enzyme
defi ciency that makes the standard therapeutic dose of mercaptopurine far too high for
their bodies. The FDA’s scientifi c advisers have recommended adding that informa-
tion to the drug’s label, too. There is a need for good studies on this topic. As personal-
ized medicine gets established, it is expected that the regulatory agencies will work on
guidelines for this system, e.g., approval of drugs packaged with diagnostic tests.
22 Regulatory Aspects of Personalized Medicine