Paul Sisson
Experts anticipate many more businesses will seek FDA approval for direct-to-consumer genetic testing after the agency blessed such a service from the company 23andMe. (Bebeto Matthews / AP)
Medical experts in San Diego said the federal government’s blessing of the nation’s first direct-to-consumer genetic testing service is sure to get aspiring competitors drooling — and that it’s not necessarily a good thing.
They’re reacting to the U.S. Food and Drug Administration’s newly announced approval of a test kit from 23andMe, a company based in Mountain View.
“I think other companies have had a sort of wait-and-see attitude since the FDA took action with 23andMe back in 2013,” said Joe Panetta, chief executive of Biocom, the San Diego-based trade group that represents Southern California’s biotechnology industry. He was referring to regulators suspending 23andMe’s original genetic testing service in that year due to lack of substantiation for its marketing claims.
Panetta noted that 23andMe has been something of a test case for the larger idea of direct-to-consumer genetic testing.
In 2010, San Diego-based Pathway Genomics was poised to pioneer the market with its Genetic Health Report, which tests for 70 different conditions, being sold in 6,000 Walgreens stores nationwide. The FDA decided that Pathway’s kit met the legal definition of a medical device and was thus subject to review because “these tests have not been proven safe, effective or accurate,” the agency said.
The Pathway-Walgreens plan quickly fell apart and the FDA sent roughly 20 more rejection letters to companies across the nation advertising similar tests. In 2013, it followed up with a sternly worded warning letter to 23andMe, which had continued to sell direct-to-consumer tests despite the earlier warning. The company then pulled back, focusing on genealogy services, but kept working with the government for approval of its broader genetics offerings.
Now having secured that clearance, 23andMe plans to market its testing for 10 conditions ranging from a blood-clot disorder to Alzheimer’s and Parkinson’s diseases.
Dr. Stephen Kingsmore, director of the genomic medicine institute at Rady Children’s Hospital San Diego, said he has spent about an hour looking at the details of the newly approved test and found that in most cases, it promised to detect some but not all of the genetic mutations known to cause the targeted diseases.
“You think you’re buying a car and instead you’re buying a steering wheel, you know? If you get a negative result on some of these, it doesn’t necessarily mean anything,” Kingsmore said.
Lisa Madlensky, a board-certified genetic counselor and director of the Family Cancer Genetics Program at UC San Diego’s Moores Cancer Center, had some of the same reservations.
She noted that in some cases, the scientific studies that validate the 23andMe testing apply only to people of Eastern European ancestry and thus may not be valid for those of other races and ethnicities. For example, the company’s test for dystonia, a movement disorder, has been validated only in patients of Ashkenazi Jewish descent.
This is noted in 23andMe’s write-ups about its services, but Madlensky said in her experience, patients usually don’t read all of the descriptions and back-up material to fully educate themselves on the results they’re about to receive.
“I think 23andMe has done a really good job of putting together graphics and descriptions to make things understandable, but you actually have to read through that. Back years ago, when these reports were first coming through, (customers) weren’t necessarily clicking through to read all of the information that was available to them,” she said.
One of the biggest problems, she added, is that patients need to understand the most simple fact of these genetic tests: They don’t provide an actual diagnosis. They simply indicate whether a person’s genes put him or her at risk of developing a given condition.
“Very rarely in disease prediction is it just one factor that makes or breaks it. Usually, it’s a combination of your genes, our environment, your lifestyle, and throw in a little bit of chance for good measure,” Madlensky said.
In an email, Rachel Reichblum, a spokeswoman for 23andMe, said the company’s genetic testing isn’t designed to be a diagnostic tool.
“We always recommend that if you have a family history of a condition or any concerns, you should talk to your doctor or a genetic counselor about appropriate steps to take,” Reichblum said.
Kingsmore said he’s also concerned that the direct-to-consumer testing approved Thursday by the FDA doesn’t come with a budget for doctor education, as is typically the case with newly approved drugs or medical devices.
He feared that many primary care doctors will try to help interested patients comprehend the benefits and limits of 23andMe’s offerings when they themselves haven’t been formally taught to make sense of those services.
“What that means is that you’ve to some extent really set the medical community up to fail. People don’t realize how difficult interpreting this information is. There are only 500 board-certified medical geneticists in the United States, while there are about 800,000 doctors,” Kingsmore said.
Madlensky said she regularly receives calls from, and schedules appointments with, consumers who have ordered a 23andMe test and are confused about what to make of the results. That pattern continued, she noted, even though 23andMe had been forbidden from analyzing test results for more than three years.
How could this be? The company and others like it weren’t banned from providing clients with raw data from direct-to-consumer, test-kit analyses for specific mutations at specific locations in their genomes. People also try to interpret that raw data by visiting certain websites.
“There are sites that will do it for as little as $5,” Madlensky said, adding that she has seen instances where the interpretation has caused anxiety about a false positive and others where it has flagged a real condition that needed attention.
In the end, she said, she’s generally excited about people engaging with information gleaned from their own DNA as long as they realize that they’re not getting the whole answer from the DIY approach. In all cases, she said, these kinds of tests should be followed up with a much more in-depth analysis that takes into account more possible genetic variables.
Panetta at Biocom said it’s also important to remember that today’s genetic testing — be it from 23andMe or a major medical institution — usually examines only short sections of the much larger genome, but that the field is progressing rapidly in sophistication. He said whole-genome sequencing is getting ever cheaper, meaning that what the FDA approved last week could rapidly be surpassed with broader and deeper product offerings.
“The real answer is full genetic sequencing offered over-the-counter to consumers. We’re not there yet, but I think we will be there very soon,” Panetta said.
http://www.sandiegouniontribune.com/news/health/sd-me-genetic-test-20170407-story.html
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