The FDA has given genetic testing giant 23andMe the go-ahead to sell a screening kit to tell consumers how well certain drugs will work them.
At the same time, the agency with a stark warning that most genetic tests can’t be trusted to fulfill that need.
Direct-to-consumer genetic testing is a hot and controversial topic among doctors, patients and regulators alike.
While proponents say tests like 23andMe give consumers a better understanding of and agency over their own health (at a relatively low price point), skeptics argue that direct-to-consumer medical tests don’t paint a complete picture.
And doctors – let alone patients – rarely have the right training to interpret the complex risk factors signaled by genetic variants, experts caution.
The FDA has green-lighted a new DNA test from 23andMe that will tell consumers how their DNA might alter the effectiveness of drugs. Simultaneously, the agency issued a warning that the results should not be used to inform decisions about what medications to take
Some 12 million Americans took at-home genetic tests in 2017.
DNA testing’s popularity has its roots in genealogy, but the companies offering the tests are looking to health information as the future of their businesses.
This is putting the Food and Drug Administration (FDA) in an awkward position that is partly of its own making.
Up until 2017, the FDA had every intention of regulating direct-to-consumer DNA tests.
Then, it changed its tune.
After keeping a tight grip on the flow of genetic tests onto the market, Comissioner Scott Gottlieb announced in November of last year that the FDA would let genetic tests ‘to be exempted from premarket review under certain conditions.’
And so the flood gates opened, as the FDA bent to complaints that its regulation of the tests would ‘bring innovation to a halt,’ recalls Dr Peter Lurie, executive director of the Center for Science in the Public Interest (CSPI) and a former FDA insider recalls.
Genetic tests no longer need FDA-approval to be marketed to consumers, but having the agency’s seal of approval certainly lends them legitimacy.
And while it has abdicated control over the tests, the FDA is still responsible for warning the public of the potential risks of products, including, it seems, DNA tests.
Now, 23andMe’s forthcoming pharmacogenetic test is the first and, thus far, only such kit to get the FDA’s approval.
Pharmacogenetic tests screen for a number of genes linked to how individuals respond differently to a variety of drugs.
The 23andMe test purports to provide genetic variation information pertaining to 50 common over-the-counter and prescription medicines.
But the FDA also put out a warning about how this information should be used, and by whom.
‘What’s interesting about it is the pairing of the 23andMe device with the warning announcement by the Drug and Device Center directors,’ says Dr Lurie.
He sees a confusing tension between the two statements.
There are all these little exemptions that could end up swallowing the whole rule [of regulation]. And, in this case, they already have
Dr Peter Lurie, executive director of the Center for Science in the Public Interest
The FDA approved 23andMe’s test to identify gene variants
‘There’s both of these things: the [approval of] the very restricted use for which the 23andMe product is labeled – for detection of variants – but it is not supposed to talk about the practice of medicine, or drug selection or patient selection.’
In other words, consumers can take the test, find out what gene variants they have – with names like ‘CYP2C19*2,’ which is very different from ‘CYP2C19*3‘ – but the FDA is insistent that they not go looking for what those variants mean about their drug responsiveness or make any medical decisions accordingly.
The test is approved to be purchased and taken by consumer, but consumers are not approved to do anything with the information they get back.
Dr Lurie says the warning is made ‘in good faith,’ but is skeptical it will really stop consumers and their doctors from interpreting and misinterpreting their genetic information and letting it have any bearing on their decisions.
‘Despite a warning from the FDA, it’s likely that patients that can get the test independently from doctors will make a decision based on this, and the doctors will not be well-equipped to fully understand the implications of the test,’ he says.
Even doctors that might be prescribing these 50 drugs – including one used to help reduce the risks of heart attacks – are not geneticists or genetic counselors, and are not trained to interpret the meaning of these genetic risk factors.
Plus, while their accuracy has improved, genetic tests themselves are imperfect.
Dr Lurie conducted a study in 2015 on a number of lab-developed tests, including (but not limited to) genetic ones.
‘There appeared to be public health harms as a consequence of various problems of the test,’ mostly false positives and false negatives, says Dr Lurie.
His findings were posted on the FDA website in the form of a warning to consumers that the tests are not 100 percent reliable – until recently. The warning and paper have been removed from the FDA’s site (Daily Mail Online could not verify why this was done).
Without the requirement of FDA approval, tests can come to market without solid proof of their accuracy and whether or not the results they return to consumers hav any clinical benefits.
Exempting the tests thus far could also be a slippery slope toward consumers buying potentially harmful products that they don’t understand.
We have already seen this with the dietary supplements and homeopathy indutstries, Dr Lurie says.
‘There are all these little exemptions that could end up swallowing the whole rule [of regulation],’ he says.
‘And, in this case, they already have.’