Bobbing For Information: FDA Approval of 23andMe Testing

It seems fitting that the FDA announced on Halloween that it would allow genetic testing company 23andMe to market its pharmacogenetics test directly to consumers (DTC).(1) The test identifies changes in eight genes involved in drug metabolism that can affect how an individual would respond to certain classes of drugs. The very next day, the FDA released a “Safety Communication” warning patients and physicians to be wary of companies marketing genetic tests claiming to predict drug response.(2) “Be aware that most genetic tests that make claims about the effects of a specific medicine are not supported by enough scientific information or clinical evidence,” is one of the recommendations for patients in the safety communication. So, what does this mean for consumers who are accessing their genetic information from a variety of service providers who sequence their DNA and report back findings in reports? Are consumers getting a trick or a treat? The great news is that this first DTC pharmacogenetic test has the potential to truly help many patients in the tailoring of therapeutic drugs to individuals. The 23andMe test detects the “variants” in the key genes that  are responsible for the majority of how drugs are metabolized in the body. Well established clinical studies have demonstrated the reproducibly accurate, predictive value of the genetic changes in those eight genes. Using the pharmacogenetic test information, physicians can better determine the right amounts of drugs to give to their patients as well as better assess potential adverse drug interactions.

The more sobering news is as clear as the language of the Halloween press release. The press release appears to focus more on what the 23andMe’s test is NOT meant to do, versus what it is capable of doing. FDA’s OIVDRH Director Tim Stenzel’s statement is fairly cautionary: (excerpting the key phrases here) “ does not determine….does not provide… does not diagnose…..Consumers should not use….Any medical decisions should be made only after discussing the results with a licensed health care provider….” Likewise the press release goes on to state the 23andMe test, (excerpting key phrases again here) “is not intended to….does not describe an association between… providers should not use the test to make any treatment decisions. Results from this test should be confirmed….” While the FDA should be praised for the rigor applied in the approval process for DTC genetic tests, of all the tests being provided, 23andMe’s pharmacogenetic test can provide sound, actionable information for individuals to take charge of their own health conditions. Far better to support this test with enthusiasm than not addressing the suitability of genetic tests that report on whether an individual has a greater risk of suffering from “Misophonia”, or greater mosquito bite frequency, or likelihood of having a fear of heights (yes, these are tests provided by 23andMe too, and no, the FDA does not review such so called “low risk general wellness products”). It is certainly very important to make sure tests that give information that relate to health decisions are accurate and properly understood and acted upon in a healthcare setting; but there are only 4 DTC genetic tests approved by the FDA to date, all from 23andMe.(3) Contrast this with the almost 4,000 known genes with a “phenotype-causing mutation” listed in the Online Mendelian Inheritance of Man (OMIM) database.(4)

As more genetic tests become available to consumers and consumers become more sophisticated about using information derived from their own genomes, knowledge from these tests will be the ultimate treat for patients. And, the trick for the FDA will be hitting the right balance between encouraging rapid innovation in genetic information DTC versus “regulating out” the clearly dangerous or meaningless.

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November 2, 2018






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