FDA Announces New Rules Meant to Target Quality of Laboratory Developed Tests

April 30, 2024
New rules were seen as necessary now that so-called LDTs are manufactured at higher volumes, with some reports that certain tests were not working properly.

The FDA has taken action to “ensure the safety and effectiveness of laboratory developed tests, or LDTs, which are used in a growing number of health care decisions and about which concerns have been raised for many years.”

LDTS are defined as in vitro diagnostic products (IVDs) “intended for clinical use and designed, manufactured and used within a single clinical laboratory that meets certain regulatory requirements. IVDs can play an important role in health care; they are used in the collection, preparation and examination of specimens taken from the human body, such as blood, saliva or tissue. They can be used to measure or detect substances or analytes, such as proteins, glucose, cholesterol or DNA, to provide information about a patient’s health, including to identify, monitor or determine treatment for diseases and conditions.”

The FDA specifically ruled that “IVDs are devices under the Federal Food, Drug, and Cosmetic Act (FD&C Act) including when the manufacturer of the IVD is a laboratory. Along with this amendment, the FDA issued a policy to phase out, over the course of four years, its general enforcement discretion approach for LDTs.”

LDTs are used for such purposes as “newborn screening, to help predict a person’s risk of cancer, or aid in diagnosing heart disease and Alzheimer’s.” The risk involved with using many LDTs has increased since initial rules of enforcing their quality were enacted by the FDA, partially because they are used more widely and manufactured at higher volumes. Indeed, the FDA is “aware of numerous examples of potentially inaccurate, unsafe, ineffective or poor quality IVDs offered as LDTs that caused or may have caused patient harm.”

The FDA is now intending to exercise enforcement for “certain categories of IVDs,” including “currently marketed IVDs offered as LDTs that were first marketed prior to the date of issuance of the final rule” and “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.”