FDA Final Rule Changes

The FDA has issued a significant final rule that changes the regulatory landscape for Lab Developed Tests (LDTs). This new rule, which takes effect on July 5, 2024, ends the agency’s long-standing practice of exercising enforcement discretion for most LDTs. The FDA now explicitly includes LDTs under the definition of in vitro diagnostic (IVD) devices regulated under the Federal Food, Drug, and Cosmetic Act (FDCA).

Key Changes and Phases

  1. Phase-Out Period: The FDA has set a four-year phase-out period for its enforcement discretion over LDTs, structured in stages:
    • Stage 1: One year after the rule’s effective date, compliance with Medical Device Reporting (MDR), correction, and removal reporting, and complaint file requirements.
    • Stage 2: Two years after the effective date, compliance with additional requirements such as registration, listing, and labeling.
    • Stage 3: Three years after the effective date, compliance with most quality system (QS) requirements.
    • Stage 4: Three and a half years after the effective date, premarket review requirements for high-risk IVDs.
    • Stage 5: Four years after the effective date, premarket review requirements for moderate and low-risk IVDs​(Mintz)​​ (Quarles)​.
  2. Exemptions and Discretion: Certain LDT categories will continue to benefit from enforcement discretion:
    • LDTs within the Veterans Health Administration and Department of Defense.
    • Tests approved under the New York State Department of Health’s Clinical Laboratory Evaluation Program.
    • LDTs developed and used within a single healthcare system to meet unmet medical needs of patients within that system.
    • 1976-type LDTs, HLA tests used in transplantation, and forensic tests​ (Mintz)​​ (American Hospital Association)​​ (Quarles)​.
  3. Public Health Emergency Policies: The FDA has also issued draft guidance for LDTs during public health emergencies, outlining conditions under which certain enforcement discretions will apply, akin to policies during the COVID-19 and mpox emergencies​ (Gibson Dunn)​.


The rule aims to ensure the safety and effectiveness of LDTs, addressing concerns that some LDTs might not provide accurate results or perform as well as FDA-approved IVDs. This move has garnered both support and opposition. Supporters argue it ensures higher standards and patient safety, while opponents fear it could limit access to essential diagnostic tests, increase healthcare costs, and burden smaller laboratories​ (American Hospital Association)​​ (Quarles)​​(Gibson Dunn)​.

Legislative and Legal Reactions

There is significant scrutiny and potential legislative action in response to the FDA’s final rule. Some lawmakers argue the FDA has overstepped its authority, which may lead to legal challenges and renewed efforts to pass the VALID Act, a proposed law that would provide a more tailored regulatory framework for LDTs​ (Gibson Dunn)​.

For more detailed information, you can refer to the FDA’s announcement and other resources from law firms and healthcare organizations that have analyzed the rule.