Is it safe? I heard that there have been safety concerns.

In a 2018 safety communication, the FDA warned the public about the FDA’s concerns genetic tests making claims about how to use the genetic test results to manage medication treatment that are not supported by recommendations in the FDA-approved drug labeling or other scientific evidence. Clinicians order tests to help them and their patients make better informed decisions. At that time, the FDA recommended that such decisions should be based on solid and reliable science.

What exactly is the FDA?

The FDA is an agency within the U.S. Department of Health and Human Services, protects the public health by assuring the safety, effectiveness, and security of human and veterinary drugs, vaccines and other biological products for human use, and medical devices. The agency also is responsible for the safety and security of our nation’s food supply, cosmetics, dietary supplements, products that give off electronic radiation, and for regulating tobacco products.

What is the FDA’s viewpoint on pharmacogenetic testing?

Pharmacogenetic testing is a type of genetic test that in some instances can predict how a person will respond to specific medications. Thus, this type of testing offers promise for informing the selection or dosing of some medications for certain individuals. When there is sufficient scientific evidence demonstrating a relationship between how a person’s genes may impact their metabolism of a drug or how they may respond to the drug, this information can be useful for health care providers. However, for many medications, there is not sufficient scientific evidence to support using pharmacogenetic test results to inform prescribing decisions.

What has the FDA done since 2018 to ensure that pharmacogenetic testing is accurate?

On February 20, 2020, in a statement from Jeffrey E. Shuren, MD, JD, Director – CDRH Offices: Office of the Center Director, the FDA introduced a collaboration between the FDA’s Center for Devices and Radiological Health and Center for Drug Evaluation and Research intended to provide the agency’s view of the state of the current science in pharmacogenetics. The FDA released a web-based resource that includes a table that describes some of the gene-drug interactions for which the FDA believes there is sufficient scientific evidence to support the described associations between certain genetic variants, or genetic variant-inferred phenotypes, and altered drug metabolism, and in certain cases, differential therapeutic effects, including differences in risks of adverse events.

What does the FDA table recommend?

The table includes certain established gene-drug interactions that appear in FDA-approved drug labeling. Recognizing, however, that not all supported gene-drug interactions may be found in current FDA labeling, the table also includes some additional gene-drug interactions that are consistent with the current FDA labeling and for which there is sufficient scientific evidence based on published literature. This literature-based scientific evidence is often used in support of the recommendations found in professional guidelines used by clinicians. The FDA is constantly updating this resource.

For the pharmacogenetic associations listed in this table, the FDA has evaluated and believes there is sufficient scientific evidence to suggest that subgroups of patients with certain genetic variants, or genetic variant-inferred phenotypes (such as affected subgroup in the table below), are likely to have altered drug metabolism, and in certain cases, differential therapeutic effects, including differences in risks of adverse events.

The fact that the FDA has included a particular gene-drug interaction in the table does not necessarily mean the FDA advocates using a pharmacogenetic test before prescribing the corresponding medication unless the test is a companion diagnostic. Tests that are essential for the safe and effective use of a therapeutic product, including those that identify patients for which the drug is contraindicated, are companion diagnostics.

What is in the FDA table?

Over the next few blogs, I will detail the FDA recommendations in parts.

Section 1: Pharmacogenetic Associations for which the Data Support Therapeutic Management Recommendations