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Regulatory Intel
May 03 2024
FDA Finalizes Rule on Laboratory Developed Tests

On April 30, 2024, the FDA unveiled its Final Rule regarding laboratory developed tests (LDTs). The rule makes explicit that in vitro diagnostics (IVDs), which are regulated as devices, include those developed by a laboratory.

To date, FDA has exercised enforcement discretion for most LDTs, generally not enforcing IVD requirements—e.g., registration and listing, reporting adverse events to FDA, current good manufacturing practices (cGMPs), premarket review by FDA, etc.  Going forward, most LDTs will be regulated by the FDA’s Center for Devices and Radiological Health (CDRH) and subject to the same rules as all other IVDs.

The rule is poised to have a significant impact on commercial labs, provider-based labs, in vitro diagnostics manufacturers, and pharmaceutical firms.

FDA’s finalization of the Rule comes after several years of contending with unsuccessful legislative endeavors and pushback from industry and clinicians.


Phaseout plan: FDA will incrementally ramp up enforcement over a four-year period.

Enforcement discretion: For certain types of LDTs, FDA will continue its existing enforcement discretion policies and generally not enforce all or some applicable requirements. Examples (partial list) include tests developed for an unmet need, as well as those that are already marketed—provided they are not modified, or that they are modified only in certain limited ways.


For starters…

Court challenges: This rule kicks off a broader debate, and several labs and other stakeholders will likely challenge this in the courts. What will this look like, and how will it impact FDA’s four-year plan?

Administrative capacity: There will be many new applications coming into CDRH. Do they have the capacity to review the applications in a timely manner?

Reaction from Congress: Several members claim that FDA has overstepped their authority. For example, last September Sen. Bill Cassidy, ranking member of the Health, Education, Labor, and Pensions (HELP) Committee, asserted that FDA’s recent efforts to “unilaterally pursue regulatory reforms through rulemaking” go beyond its statutory authority. He recently issued a Request For Information to stakeholders on ways to improve clinical test regulation. What will his next steps be?

VALID Act: The bipartisan Verifying Accurate, Leading-edge IVCT Development (VALID) Act nearly passed in 2022; it has been reintroduced in the House this session, but not the Senate. How will this develop?


The agency plans to host a webinar to review the Final Rule. Date TBD.


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