After Decades of Debate, FDA Moves to Regulate In-House Lab Tests

After decades of intense debate and stalled legislation, the Food and Drug Administration has taken a critical step in overseeing a vast category of lab tests that reach patients without any federal agency checking to ensure they work the way their makers claim.

Among the tests that are not reviewed by the FDA: popular prenatal genetic screenings that ProPublica recently reported on, as well as certain cancer screenings and tests for rare diseases.


This story was originally published by ProPublica and is republished here under a Creative Commons license.


Last Wednesday, a notice of the proposed rule was posted. This is the first concrete evidence that the FDA is preparing to apply its regulatory powers to these lab tests.

“A modern oversight framework that is specifically tailored to assuring tests work is critical to position ourselves for the future — whether it is preparing for the next pandemic or realizing the full potential of diagnostic innovation,” an FDA press officer said in a statement to ProPublica.

Peter Lurie, president and executive director of the Center for Science in the Public Interest, applauded the move. “It’s exciting to see the agency taking concrete steps to address this long-standing hole in the public health safety net,” he said.

The agency’s hands-off approach to lab-developed tests — which are designed, manufactured and used by a single lab — traced back to a time when they were deployed at a small scale. The idea was to spare hospital labs, for example, from the time, money and hassle of getting approval in Washington whenever they needed to create a simple test for their own patients.

Nowadays, so-called LDTs are an enormous part of the health care system, including a number of high-stakes tests made by commercial companies. Because they aren’t registered with the federal government, nobody knows how many exist. A 2021 study by Pew Charitable Trusts estimates that 12,000 labs are likely to use such tests, many of which process thousands of patient samples each day. Currently, the Centers for Medicare and Medicaid Services reviews lab operations, but it doesn’t check whether the tests themselves are clinically valid.

“It’s exciting to see the agency taking concrete steps to address this long-standing hole in the public health safety net,” said Lurie.

While these tests “play an important role in our health care system,” said the FDA press officer, the agency “is very concerned about problematic LDTs currently used in the U.S. that might not provide patients with accurate and reliable results.”

ProPublica’s investigation of prenatal genetic screenings detailed how the FDA doesn’t review the tests before they reach patients, nor does it verify marketing claims made by companies that sell them. False positives, false negatives and uncertain results about genetic anomalies have sometimes led to devastating consequences for families, the investigation found. Companies aren’t required to publicly report instances of when the test gets it wrong, and no federal agency is able to recall faulty tests. (ProPublica also made a guide to prenatal screening tests for expectant parents.)

The next step for the FDA is to publish a draft of the proposed rule, which seems likely to happen in August. It will go through a public comment period, and then the agency will develop a final rule. Both the proposed and final rules need to be cleared by the Department of Health and Human Services and the Office of Management and Budget. Experts said this process could go relatively quickly, or it could take a year or more, pushing up against a 2024 election that might change priorities in Washington.


Over the years, a large coalition of labs, professional associations and academic medical centers have argued that FDA oversight over the lab tests would be overly burdensome and inflexible — so much so that it would stunt critical innovations and limit patient access to quality health care. Opponents also express concern about the FDA’s capacity to oversee the tests.

Mary Steele Williams, executive director of the Association for Molecular Pathology, said in a statement to ProPublica that AMP is updating its proposal for an alternative approach to lab testing reform, one that doesn’t rely on the FDA. Instead, it recommends modernizing existing regulations through CMS, “which we believe to be the most effective and streamlined approach.”

Williams also said that AMP intends to continue working with other institutions to “raise our shared concerns with FDA regulation” over lab-developed tests. It remains committed, she said, “to working with Congress and other stakeholders to establish a more efficient regulatory framework that ensures high-quality patient care while continuing to foster the rapid innovation and promise of new diagnostic technologies.”

An earlier effort by the FDA to rein in LDTs came in 2014, when the agency issued draft guidance. But after facing nearly two years of stiff opposition, the agency pulled it. One of the strongest critics was the American Clinical Laboratory Association, a national trade group. It challenged the FDA’s authority over the tests by filing a citizen petition and making clear its intent to sue if necessary.

In a statement last Wednesday to ProPublica, an ACLA spokesperson said the association has long taken the position that any regulation of LDTs must be done through legislation. It should be a framework “that recognizes the essential role of clinical laboratories in advancing public health, preserving and fostering innovation and maintaining access to critical testing services,” the spokesperson said, adding: “We stand ready to provide expertise and technical assistance to Congress.”

There have been several efforts to reform lab testing through Congress over the years, and the FDA has signaled that it welcomes legislative action that would create a modern framework specifically tailored to clinical testing.

In 2022, a bipartisan bill known as the VALID Act seemed to have its best shot at passing, having gathered momentum after the scandal over fraudulent Theranos blood tests and the coronavirus pandemic. But, facing pushback, it was dropped from a must-pass bill at the end of the year. While ACLA’s spokesperson said the association worked with the bill’s sponsors to help shape it, in the end, ACLA didn’t endorse it. The act was reintroduced in the House in March.

If the FDA enacts a new rule, supporters anticipate legal challenges, said Cara Tenenbaum, a former policy adviser for the agency whose consultancy signed onto a recent letter urging it to assert oversight.

But over the past decade, the FDA tried every alternative to address what it sees as a public health problem, she said.

“All they have left is their existing device authority,” Tenenbaum said. “They’ve been backed into a corner, if you ask me.”

The FDA pushing ahead with a proposed rule, even while legislation is on the table, makes sense because “the clock is ticking on the administration,” said Lurie, a former top FDA official who worked on lab testing reform.

At the same time, he said, “the problem is long-standing and, frankly, in fact, growing. More and more products come to market every day, and very few of them get regulated.”



Anna Clark is a reporter for ProPublica covering issues in the Midwest.

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