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# 4-Year Enforcement Discretion for LDTs: Final Rule
- URL: https://www.fdaweb.com/4-year-enforcement-discretion-for-ldts-final-rule/
- Published: 2024-04-29T12:00:00.000Z
- Updated: 2026-09-14T14:29:31.000Z
- Author: David McFarland
- Tags: Devices, #legacy-id-D5156871

FDA has issued its long-awaited [final rule](https://public-inspection.federalregister.gov/2024-08935.pdf?ref=fdaweb.com) that amends its regulations to make explicit that laboratory-developed tests (LDTs) are in vitro diagnostic devices (IVDs) regulated under the Federal Food, Drug, and Cosmetic Act (FD&C Act). In conjunction with the final rule, the agency issued a policy to phase out over four years its general enforcement discretion approach for LDTs, and it issued targeted enforcement discretion policies for certain categories of IVDs manufactured by laboratories.

“LDTs are being used more widely than ever before – for use in newborn screening, to help predict a person’s risk of cancer, or aid in diagnosing heart disease and Alzheimer’s,” commissioner **Robert Califf** is quoted in a [release](https://www.fda.gov/news-events/press-announcements/fda-takes-action-aimed-helping-ensure-safety-and-effectiveness-laboratory-developed-tests?ref=fdaweb.com) as saying. “The agency cannot stand by while Americans continue to rely on results of these tests without assurance that they work. The final rule announced today aims to provide crucial oversight of these tests to help ensure that important health care decisions are made based on test results that patients and health care providers can trust.”

FDA says that because LDTs have become much more complicated and have higher risks than those historically used, its enforcement discretion approach has become obsolete. Today, the agency says, many LDTs are “used more widely, for a larger and more diverse population, with large laboratories accepting specimens from across the country. LDTs also increasingly rely on high-tech instrumentation and software, are performed in large volumes and are used more frequently to help guide critical health care decisions… Moreover, there is a growing body of evidence that demonstrates that some IVDs offered as LDTs raise public health concerns; for example, they do not provide accurate test results or do not perform as well as FDA-authorized tests, including from published studies in the scientific literature, the FDA’s own experience in reviewing IVDs offered as LDTs, news articles and class-action lawsuits.”

As for its targeted enforcement going forward, FDA intends to exercise enforcement discretion regarding premarket review and most quality system requirements for certain categories of IVDs, including but not limited to:

- Currently marketed IVDs offered as LDTs that were first marketed prior to the date of issuance of the final rule.
- LDTs manufactured and performed by a laboratory integrated within a health care system to meet an unmet need of patients receiving care within the same health care system when an FDA-authorized test is not available.

Additionally, the agency has issued two draft guidances — one [provides the agency’s thinking](https://www.fda.gov/regulatory-information/search-fda-guidance-documents/enforcement-policy-certain-in-vitro-diagnostic-devices-immediate-public-health-response-absence?ref=fdaweb.com) about an enforcement discretion policy for certain laboratories offering tests as part of an immediate response to an emergent situation, such as an outbreak of an infectious disease, and the other [provides insight](https://www.fda.gov/regulatory-information/search-fda-guidance-documents/consideration-enforcement-policies-tests-during-section-564-declared-emergency?ref=fdaweb.com) into the FDA’s thinking about the factors the agency intends to consider when developing a policy regarding enforcement discretion for certain IVDs during a declared public health emergency.