On March 31, 2025, the U.S. District Court for the Eastern District of Texas issued a landmark ruling that vacated the FDA's Final Rule on Laboratory Developed Tests (LDTs). This decision has significantly positive implications for labs that frequently use LDTs as a part of their workflows.
LDTs have long played a vital role in the evolution of diagnostic medicine. While commercial test kits support a variety of clinical diagnostic tests, they are required to go through the FDA’s traditional premarket review process. LDTs serve as an alternative that allows labs to flexibly respond to emerging or contextual clinical needs, and have historically had a regulatory compliance structure that is designed with this in mind.
Before the FDA's attempt to assert regulatory authority, LDTs were—and now, following the recent ruling, continue to be—regulated under the Clinical Laboratory Improvement Amendments (CLIA) by the Centers for Medicare & Medicaid Services (CMS), not the FDA. This regulatory framework has enabled many certified labs across the country to develop high-quality tests quickly and responsibly—especially when no FDA-approved options exist.
Over-regulation of LDTs can have significant impacts on labs that rely on them for:
The court's ruling puts a block on the FDA's efforts to regulate LDTs as in vitro diagnostic products (IVDs). This decision is seen as a victory for laboratories concerned about the potential burdens of additional FDA regulation.
Many industry experts thought that the FDA’s interventions would complicate compliance, slow innovation, raise costs, and restrict patient access to critical diagnostics—especially in areas where FDA-approved tests are unavailable or too generalized to be useful. As such, the recent court ruling preserves the ability to continue offering validated and timely diagnostic tests without undue additional regulatory burden.
As noted in the court’s opinion, “the text, structure, and history of the FDCA and CLIA make clear that FDA lacks the authority to regulate laboratory-developed test services.” The opinion elaborates that Congress specifically chose to regulate clinical laboratories and their services separately through CLIA, rather than through the FDA.
After the victory, presidents of major laboratory organizations celebrated the court’s ruling:
As it stands, the FDA exerts no regulatory oversight over LDTs, meaning CMS’ CLIA regulatory standards will continue to govern matters related to LDT compliance. However, the matter has been remanded to the Secretary of Health and Human Services (HHS), so future regulatory efforts cannot be ruled out—whether through new rulemaking, legislative proposals, or legal appeals. At the time of writing, the FDA has not publicly indicated if it intends to appeal the decision, but we are continuing to monitor the situation closely.
Streamline Scientific stands with industry experts and labs nationwide to fully support this decision, which aligns with our goals of supporting laboratories in delivering high-quality molecular diagnostic services through streamlined processes and innovative solutions. This ruling will help maintain access to vital testing services while allowing laboratories to focus on improving patient care.
Laboratory regulatory oversight is an ever-changing landscape, and keeping up with it can be a challenge. We remain committed to supporting our laboratory partners by keeping them abreast of regulatory changes. If you have questions about how this ruling may affect your laboratory operations, please contact our team of specialists.
Follow the link if you are interested to see the court’s full memorandum opinion and order, as published by the ACLA.