On August 19, 2024, the Association for Molecular Pathology (AMP) sued the FDA to challenge a new rule that allows the FDA to regulate laboratory developed tests (LDTs).[1] The rule, which became effective on July 5, 2024,[2] explicitly categorizes in vitro LDTs intended for clinical use as medical devices, placing such LDTs within the purview of the FDA.[3] The complaint was filed in the Southern District of Texas. AMP’s suit follows another suit filed by a trade association, the American Clinical Laboratory Association, targeting the same rule.[4]

As we previously discussed, the FDA had historically opted for discretionary non-enforcement of requirements for most LDTs. The recent rule provides for a four-year, five-stage period during which the FDA will phase out this discretionary approach for many LDTs. [5] During this time, the FDA will begin implementing medical device reporting requirements for such LDTs.[6]

The Complaint estimates that, if implemented, the new LDT rule could cost up to $114 billion in one-time expenditures and $14.31 billion in annual recurring costs.[7] The global in vitro diagnostic market is estimated to be about $82.4 billion.[8] In vitro diagnostic development was accelerated during the COVID-19 pandemic, perhaps partly due to a facilitative regulatory environment.[9]

In its complaint, AMP argues that the Food, Drug, and Cosmetic Act (“FDCA”) and Clinical Laboratory Improvement Amendments of 1988 establish congressional intent that LDTs are not under the FDA’s authority.[10] AMP explicitly invokes the “major questions doctrine” in alleging that Congress did not clearly wish to assign to the FDA a question of such economic significance.[11]

AMP, founded in 1995, is a non-profit group focusing on molecular pathology. AMP has over 2,900 members, including individuals from academic and community medical centers, government, and industry.[12]