FDA Takes First Steps to Regulate Single-Lab Tests

The US Food and Drug Administration has announced that it is setting in motion a regulatory process to regulate laboratory-developed tests (LDTs), diagnostics that are created, marketed, and used within single laboratories. As of now, such tests can be used in the United States without strong clinical evidence of their benefit.

Although some critics have argued that this increased oversight will slow innovation, when the regulations are in place they should relieve a confusing dual-track situation in which independently created biomarker panels may compete with other tests already marketed by manufacturers of large-scale diagnostic tests that have undergone more rigorous FDA assessment.

The future regulation can be expected to have a significant impact on testing and drug treatment for rheumatologic conditions, given that many of the tests they use to diagnose and treat patients have been marketed as LTDs.

For instance, a multi-biomarker disease activity test for rheumatoid arthritis, commercially available as Vectra DA, is currently unregulated as an LTD.

The proposed regulations would also have governed the release of a new biomarker panel for early diagnosis of rheumatoid arthritis (RA) publicly promoted by Quest Diagnostics a year ago. Without providing published efficacy of its new panel beyond reports at a few conferences, the company added the marker 14-3-3eta (an LTD) to two well-established biomarkers for RA, marketing the combination as a better way to identify early RA.

With certain exceptions (tests that are low risk, apply to rare diseases, are used for transplantation or forensices, or involve diseases for which there is no other diagnostic option), LDTs would be subject to pre-market review under the new regulations, as well as to other oversight requirements similar to those that apply to other tests already on the market.

The action demonstrates FDA's commitment to "personalized medicine" that gets the right treatment to the right patient, said FDA Commissioner Margaret Hamburg MD in a statement. "Inaccurate test results could cause patients to seek unnecessary treatment or delay and sometimes forgo treatment altogether," she added.

Today's announcement is a legally required notice that after 60 days the FDA will publish draft guidance for public comment. Phase-in will be slow: The Agency will require manufacturers of "moderate risk" LDTs to begin registration of tests within six months after the guidance is finalized, and companies will be given years to complete the process.

National Institutes of Health Director Francis Collins MD PhD praised the FDA action as "leveling the playing field for all test manufacturers" by "ensuring the safety and efficacy of LTDs."

The FDA also issued final guidance on development, review, and approval of "companion diagnostics," tests created to identify patients most likely to benefit or suffer harm from a particular drug, such as the genetic test for sensitivity to the gout drug allopurinol.