FDA Panel Urges Caution on Genetic Test Kits

Advisory Panel Is Wary of Genetic Testing That Is Sold Directly to Consumers

From the WebMD Archives

March 9, 2011 -- An FDA advisory panel has urged federal regulators to go slowly in allowing companies to sell genetic testing kits directly to consumers, amid worries that test results could be easily misinterpreted.

The panel recommended that the FDA require sign-off from medical professionals either for ordering most tests or for interpreting the results. That would mean that tests for many diseases or conditions -- and delivery of results -- would not be available without what amounts to a prescription.

The FDA doesn’t have to follow the recommendations of its advisory panels, but often does.

The vast majority of genetic tests are available only through doctors or genetic testing centers, while results are generally interpreted by doctors and a relatively new industry of genetic counselors.

But a cottage industry of direct-to-consumer testing companies sprang up in recent years. The industry recently caught the eye of regulators, who essentially warned several companies that their tests were not able to predict health conditions as reliably as advertised.

The FDA has since decided to more closely police the industry and is deciding what kinds of tests deserve closer control and which ones could still be available direct-to-consumer (DTC).

“A lot of us feel that these tests are not going to be safe enough to be in DTC,” says George Netto, MD, an associate professor and prostate cancer researcher at the Johns Hopkins University School of Medicine and a member of the panel.

Genetic Role in Disease

It is rare for a genetic mutation to cause a condition directly, as it does in Huntington’s disease. In most cases the link between mutations and disease depend on complex interactions between many mutations, environmental factors like diet, and interactions with other health conditions.

For example, several gene mutations are known to increase the risk for hypertension. But having the mutation does not necessarily lead to hypertension, and factors including exercise, smoking, fatty food, and stress also play important roles. At the same time, having hypertension is a risk factor for cardiovascular disease but is itself intertwined with other causes.

How can a consumer determine whether a positive test actually increases their risk of dying from a heart attack?

Continued

At the heart of the FDA’s dilemma is how to balance patients’ rights to information about their risks for disease with the need to have professionals involved in the interpretation of results that can cause consumers to worry or to seek out medical care.

“Medical students don’t understand it and practicing docs don’t understand it,” says David Rahsohoff, MD, an epidemiologist from Yale University and a member of the panel. “We certainly can’t expect consumers to do that.”

But companies warned that aggressive regulation would stifle patients’ ability to improve their health by dealing with known health risks. Just because the connections between many gene mutations and disease are poorly understood doesn’t mean patients should not have access to tests, says Mary K. Pendergast, a board member of the drug company AesRx.

We can’t live our lives where we can’t know anything until everything is known,” said Pendergast, a lawyer and industry consultant who served for seven years as FDA’s deputy commissioner.

FDA Scrutiny of Genetic Testing Kits

Last year, FDA scrutiny prompted Walgreens to pull back on a decision to sell genetic testing kits from a company called Pathway Genomics.

Ed MacBean, the company’s vice president of product management, acknowledged his company had “treaded into” an uncertain business situation, given the FDA’s move.

Other companies, like 23andMe, offer consumers genetic testing kits directly to consumers over the Internet. The company’s web site promises consumers insight into traits from baldness to muscle performance and the chance to “discover risk factors for 95 diseases” for $199.

The company was founded by Anne Wojcicki, wife of Google co-founder Sergey Brin.

Alberto Guttierez, PhD, director of the FDA’s office of in vitro diagnostics, says the agency would look at tests on a case-by-case basis to decide if they should be available directly to consumers.

Tests for genes that affect prescription drug metabolism are likely to remain restricted since the drugs themselves can only be obtained under a doctor’s care. But other tests helping predict metabolism of certain foods would probably have fewer safety implications and may enjoy easier sales for companies.

Continued

“It’s going to depend on the test and what they want to claim and how it’s offered,” he told reporters.

The agency will look at the quality of scientific data connecting a test to the disease it’s supposed to predict and at “whether people can understand it and do something with it or not,” Guttierez says.

WebMD Health News Reviewed by Laura J. Martin, MD on March 09, 2011

Sources

SOURCES:  

George Netto, MD, associate professor, Johns Hopkins University School of Medicine.

David Rahsohoff, MD, epidemiologist, Yale University.

Mary K. Pendergast, board member, AesRx; former deputy commissioner, FDA.

Alberto Guttierez, PhD, director, office of in vitro diagnostics, FDA.

© 2011 WebMD, LLC. All rights reserved.

Pagination