Nov 24, 2015

US medical device and IVD regulators plan stronger oversight of laboratory developed tests (LDTs) as these products have become more widely used and riskier to patients and users.

The FDA’s Center for Diseases and Radiological Health (CDRH) has already issued draft guidance on how the agency plans to establish heftier regulatory requirements for LDTs, and has identified several issues related to its proposed oversight framework. The agency has cited the proliferation of LDTs throughout the US healthcare system, the growing complexity of these products and also questions regarding their accuracy in pursuing stronger market authorization requirements for these tests.

“Traditional” LDTs would continue to be lightly regulated, according to the FDA. The agency defines these products as:

  • Designed, manufactured and used within a single laboratory
  • Manufactured and used in the same facility for a patient being treated in that same facility or healthcare system
  • Made only of components legally marketed for clinical use
  • Able to be interpreted by healthcare professionals without use of additional technologies

US regulators believe that these products pose little risk to patients, and intend to continue using enforcement discretion—that is, no premarket review or quality system requirements—for LDTs falling into the traditional category.

The FDA also proposes continuing enforcement discretion for LDTs used for rare diseases. To qualify for this category, an LDT must qualify as a Humanitarian Use Device (HUD), and also be designed, manufactured and used within a single laboratory.

LDTs that would fall under Premarket Approval (PMA) or 510(k) premarket notification requirements would ultimately also have to meet quality system requirements under 21 CFR Part 820, notes the FDA, but the agency has proposed a phased-in compliance timetable for affected manufacturers. Phased enforcement would mean requiring a clinical laboratory that manufactures and uses an LDT to have a quality system in place either when the laboratory submits its PMA, or that a laboratory establishes a quality system before market launch of a 510(k)-cleared LDT.

In cases where healthcare networks offer the same tests in multiple laboratories, such tests would normally not qualify as LDTs because they are used in more than one facility; however, the FDA is seeking feedback on whether to require notifications from these networks that they offer the tests at multiple laboratories.

Emergo will provide additional details as the FDA makes them available.


  • Stewart Eisenhart