Pharmacogenetics, although in its infancy, has the potential to help predict how individual patients will respond to a given drug. Pharmacogenetics (or pharmacogenomics) is the study of "how genes affect a person's response to drugs." Across the U.S., several clinical laboratories offer pharmacogenetic (PGx) tests. Many of these laboratories offer the PGx tests as laboratory developed tests (LDTs).

The regulatory picture for PGx LDT clinical laboratory providers is evolving. On one hand, the U.S. Food and Drug Administration (FDA) appears to be encouraging PGx test development by: 1) encouraging collaboration with the agency on PGx test development; 2) recently publishing a table of gene-drug associations; and 3) soliciting stakeholder comments about the gene-drug associations in its table.

On the other hand, the FDA has recently taken actions that extend beyond its stated policy of not regulating LDTs developed in-house by CLIA laboratories. For example, the FDA issued a safety communication warning physicians and consumers about the limitations, and level of scientific substantiation, of some PGx tests and their associated software (which may be separately regulated by the FDA as a medical device).

The FDA also issued a warning letter to Inova Genomics Laboratory for allegedly "illegally marketing genetic test that claims to predict patients' responses to specific medications." The agency specifically noted that it "is unaware of any data establishing that Inova's tests can help patients or health care providers make appropriate treatment decisions for the listed drugs." The FDA then contacted several laboratories providing PGx test results—and providers of software used in PGx tests—demanding that they discontinue communicating interpretive PGx test results.

And the FDA is not the only entity taking action to influence the PGx test regulatory environment. Recently, the Coalition to Preserve Access to Pharmacogenomics Information filed a citizen petition with the FDA "in response to recent unprecedented and unlawful actions taken by FDA to suppress communication by clinical laboratories and software providers about the role of PGx in metabolism of, and response to, specific drugs."

The citizen petition, among other things, requests that the FDA 1) conduct any future policy development related to PGx tests in compliance with the Administrative Procedure Act; 2) permit clinical laboratories to include medication-specific information in PGx test reports that is included in FDA-approved drug labels or that is supported by adequate evidence; and 3) issue a revised safety communication clarifying that laboratories and software providers may communicate information about gene-drug interactions as part of genetic test reports.

PGx test providers, and organizations considering becoming PGx test providers, should consider the following:

First, consider the potential benefits and drawbacks of working collaboratively with the FDA when bringing PGx tests to market, including a CLIA-run LDT.

Next, be aware of the gene-associations in the FDA's table and consider what the presence, or absence, of a gene-drug association in the table might mean to any specific PGx test. Also, carefully weigh the pros and cons of presenting the FDA's table to physicians and, where appropriate others, who may order or take a PGx test.

Third, if appropriate, submit comments to the FDA's open docket. Comments can affect content in future iterations of the table, and can also influence future draft guidance(s) the agency may issue on PGx tests.

Further, as part of tracking the broader PGx regulatory landscape, monitor any possible public response to the citizen petition, realizing that in some instances the FDA may take significant time to meaningfully respond to the petition, and at least some of the agency's response may not be public.

Finally, PGx tests can have significant commercial value, and correlative genetic-drug information can appear on a drug's label and package insert (for example, see tegretol's prescribing information). Careful consideration, therefore, should be given to comprehensive strategies for patenting these tests.