America Needs Laboratory-Developed Tests (LDTs)

On July 31, 2014, the FDA notified Senator Tom Harkin, Chairman of the Committee on Health, Education, Labor and Pensions, of the FDA’s plan to release draft guidance documents titled, Anticipated Details of the Draft Guidance for Industry, Food and Drug Administration Staff and Clinical Laboratories,  Framework for Oversight of Laboratory Developed Tests (LDTs).1 The document describes the FDA’s proposed risk-based enforcement philosophy and dependent strategy for LDTs.

The structure and timing of the announcement are interesting since, just a year ago, Dr. Alberto Gutierrez, Director of the FDA’s Office of In Vitro Diagnostics, lamented the politicization of the guidance. Gutierrez reported the documents had been removed from his hands, and he was unsure of their status or prognosis. The American Clinical Laboratory Association was specifically cited for its strong lobbying against adding “burdensome regulations.”2 Micro managers in Congress passed a law that required a 60-day notice before issuing draft guidance on LDTs. This was designed to provide time for lobbyists to prevent issuing of the draft guidance.

Apparently as a poke in the eye, the notice of the draft guidance, including “anticipated details,” was issued just as Congress recessed for five weeks (35 days). Upon its return in September, the congressional calendar shows only nine working days before the 60 days expires on September 29, 2014. With all the hot-button issues that Congress has delayed working on, such as immigration, it seems unlikely that a new issue such as LDTs will generate enough heat to boil over. Plus, the FDA’s “anticipated details” seem reasonable, helpful, and workable.

Assuming the FDA proceeds to issue the draft guidance around October 1, the 60-day comment window will close at the end of November, after the mid-term elections. It seems unlikely that LDTs have the fuel content to become a general issue in the election. There are more than enough other issues with established hot-button response to consume most of the available ink and air time, so the timing for these proposed regulations appears favorable.

Few would argue that LDTs are useful and indeed important in healthcare today. Some tests have been used for decades. They would not have survived if they lacked utility. This is especially true when the tests are used in guiding diagnostics and treatment of very rare disorders. For example, when the patient population is small, it is nearly impossible to justify the costs and time for mainline registration. LDTs also fit in when new technology is emerging. LDTs provide a quick way to connect novel diagnostic technology with potentially diseased patients.

Outside the U.S.A., and particularly in Europe, research labs often have a side business of running the tests they develop from their research. LDTs are part of their healthcare system. This facilitates introduction of new methodology. Research staff is experienced in transferring research methods into routine assays. This process works quite well.

The anticipated details appear to provide a risk-based regulatory framework with a rational approach to focus on the risky tests first. Class 3 tests will be first priority, Class 2 (moderately risky tests) will have lower priority and longer time for compliance, and Class 1 (low-risk tests) will probably receive a waiver until a problem is discovered. The Agency plans to exercise “enforcement discretion” during the phase in period. New tests will need to show clinical validity and safety and also include postmarket safety monitoring, including adverse event monitoring.

If you are involved in ’omics research or are a vendor offering products that might be used in LDTs, I urge you to study the anticipated details carefully. The illustrative scenarios in the appendixes provide examples of how the long-term monitoring should work. Prepare and file your comments during the open window. We can only hope that Congress does not get in the way.


  2. Malone, B. Straight talk on lab-developed tests from FDA. Clin. Lab. News Oct 2013, 39(10).

Robert L. Stevenson, Ph.D., is Editor, American Laboratory/Labcompare; e-mail: