The FDA has put forward its official pitch for regulating laboratory-developed tests, a long-awaited proposal that would bring those products more in line with how the agency approaches other in vitro diagnostics.
Compared to tests built by large medtech companies and sold to labs—such as kits from Abbott, Roche, BD and others—LDTs were originally deemed a product category with comparatively lower risks. Because they’re typically manufactured in smaller volumes, the FDA initially opted not to subject them to full regulatory review; the goal was to provide smaller labs with the flexibility to diagnose rare diseases and operate on a more local scale while using techniques similar to standard tests.
However, that open door to the market has led many developers to rush in. The agency’s proposed rule (PDF) said the diagnostic industry has come to view LDTs as an alternative regulatory pathway—one that allows them to pursue an initial commercial launch before subjecting a test to FDA examination.
And, based on how they operate today, the FDA said the risks linked to LDTs have become much greater. They are increasingly based on high-tech instruments or unproven software, while also being used to guide treatment decisions for a larger and more diverse population of people.
Based on its recent experience with the rush to develop COVID-19 diagnostics, as well as the rise of companion tests that link patients with particular cancer mutations to a specific drug, the FDA said that many test systems developed by laboratories are functionally the same as more-regulated IVDs and are used interchangeably by providers—with the CDC estimating that about 70% of all medical decisions are based on some kind of lab test result.
“They involve the same materials and technologies, are intended for the same or similar purposes, are developed by and for individuals with similar expertise, and are marketed to the same patients, sometimes on a national scale,” the FDA said, adding that “there is no longer a sound basis for this distinction” based on where the two types of tests are made.
The proposed rule aims to make it clear that LDTs are to be considered medical devices that fall under the authority of the Federal Food, Drug and Cosmetic Act. The FDA said it plans to gradually phase out its previous enforcement approach, with a timeline starting after the rule is finalized. After one year from that date, for example, it will begin requiring companies to comply with medical device safety reporting requirements, while quality system requirements would kick in after three years.
The need for high-risk LDTs to undergo pre-market review, however, would not begin before October 2027; that requirement for moderate- and low-risk tests would follow no sooner than April 2028.
“Through increased FDA oversight, the public, including patients and health care professionals, should have confidence that the tests they rely on are accurate,” the FDA’s device center director, Jeff Shuren, M.D., said in a statement. “It is important that these tests be held to the same standards as other tests while helping to ensure test makers have the flexibilities they need to continue innovating and developing tests critical to the advancement of public health.”
In its own statement, the medtech trade association AdvaMed said it is evaluating the proposed rule.
“To better support patient care and public health, AdvaMed supports the establishment of a single, modernized, diagnostics-specific, risk-based regulatory framework for all in vitro clinical tests (IVCTs), regardless of where developed, and overseen by FDA,” said Zach Rothstein, executive director of AdvaMedDx. “Such a framework would increase the reach of cutting-edge diagnostics, allowing patients to benefit more rapidly and broadly, and increase the confidence of patients and providers in the latest diagnostic technologies.”
The association also pointed to previously stalled legislative efforts on Capitol Hill to revamp the FDA’s regulatory framework for diagnostic tests. “AdvaMed has been actively engaged in that effort because regulation of clinical diagnostics has not kept pace with advancements in the field, including those driving personalized medicine,” said President and CEO Scott Whitaker.
In recent years, the question of whether the FDA has any authority over LDTs became a political issue. In the final months of the Trump administration, the Department of Health and Human Services revoked the agency’s oversight, saying that clinicians should be free to use unreviewed and unauthorized LDTs for any type of condition.
That missive was reversed more than a year later, in November 2021, after Biden took the White House. At the time, lab industry groups said the back-and-forth underscored the need for a comprehensive reform of diagnostic test regulations.