Laboratory-Developed Tests Prevail as Federal Court Strikes Down FDA Oversight: Key Details and Implications

On March 31, 2025, U.S. District Judge Sean D. Jordan of the Eastern District of Texas vacated the FDA’s Final Rule that sought to regulate laboratory-developed tests (LDTs) as medical devices under the Federal Food, Drug, and Cosmetic Act (FDCA). This ruling represents a major victory for clinical laboratories, pathologists, and patients, with significant legal and regulatory ramifications .

The court ruled that the FDA (Food and Drug Administration) does not have the authority to regulate LDTs. This is because LDTs are considered professional services performed by trained laboratory professionals, rather than medical devices that can be regulated by the FDA. Additionally, a law called CLIA (Clinical Laboratory Improvement Amendments) already exist to oversees laboratory testing, making FDA regulation unnecessary. The court also noted that the FDA had previously chosen not to regulate LDTs, and Congress had declined to give them the authority to do so.

What are LDTs?

Laboratory-Developed Tests (LDTs) are a type of medical test developed and performed by clinical laboratories. Unlike traditional medical devices, LDTs are considered professional services that require specialized expertise and equipment. They are often used to diagnose rare or complex medical conditions, and can be tailored to meet the specific needs of individual patients.

The era of limited regulation under the Clinical Laboratory Improvement Amendments (CLIA) of 1988 allowed laboratories to validate their own tests. This flexibility enabled the development of life-saving tests, such as HIV viral load monitoring in the 1990s, long before commercial kits existed. These early LDTs were developed rapidly in response to urgent medical needs.

The Evolution of LDTs and Regulatory Shifts

Over time, LDTs grew more complex, and by the 2010s, innovative tests such as next-generation sequencing panels for rare genetic disorders and liquid biopsies for cancer were being developed. However, the FDA’s regulatory posture shifted from passive oversight to asserting authority, culminating in the 2024 Final Rule. The Final Rule according to the FDA was aim at ensuring the safety and effectiveness of LDTs by establishing a more comprehensive regulatory framework. This rule marked a significant shift, as the FDA had previously exercised enforcement discretion for most LDTs, essentially leaving them unregulated. This shift raised concerns that a one-size-fits-all device framework would stifle innovation and hinder the rapid development of diagnostic solutions for emerging pathogens and personalized medicine.

The Battle of Innovation and Regulation

The FDA’s rule was met with heavy resistance from the laboratory community, which argued that it would stifle innovation and hinder the development of new diagnostic tests. Advocates for Laboratory LDTs including, the Association for Molecular Pathology (AMP) and the American Clinical Laboratory Association (ACLA) had argued that the FDA’s rule would have imposed unnecessary requirements on laboratories and threatened access to safe LDTs.

The American Society for Clinical Pathology (ASCP) and the College of American Pathologists (CAP) have played significant roles in advocating for the interests of laboratories and pathologists in the regulation of LDTs. The CAP has been actively involved in shaping the regulatory framework for LDTs. They filed an amicus brief urging the court to vacate the FDA’s regulation on LDTs, arguing that it would impose unnecessary burdens on laboratories and hinder innovation. The CAP has also advocated for a risk-based approach to regulating LDTs, focusing on high-risk tests while allowing lower-risk tests to meet less stringent requirements.

Additionally, the CAP expressed support for the Verifying Accurate Leading-edge IVCT Development (VALID) Act, which aims to create a comprehensive regulatory framework for clinical laboratory tests, including LDTs. The VALID Act proposes a tiered system of oversight, exempting low-risk tests from FDA premarket review and allowing for modifications to existing tests without requiring reapproval.

At the end of a long battle of ideas, advocacy and ruling judge has nullified the FDA regulation on the oversight of LDT, agreeing with plaintiffs’ and the College of American Pathologists’ (CAP) arguments that the rule should be vacated.

The Celebration Begin!!

It is clear the court ruling has bring some relief as many Advocates celebrate as a major victory. AMP President Jane Gibson hailed the decision as a “significant victory for patients and laboratories,” while CAP President Donald Karcher praised the ruling, stating that it would prevent laboratories from being saddled with unnecessary requirements.

Dr. Eleanor Whitmore, Emeritus Director of Clinical Pathology at Stanford University, recalled the early days of LDTs, when laboratories were able to pioneer tests for HIV viral load monitoring in the 1990s without FDA involvement. She argued that the FDA’s one-size-fits-all device framework would not be able to accommodate the rapid iteration required for emerging pathogens or personalized oncology.

Whiles the FDA’s attempt to regulate Laboratory Developed Tests (LDTs) has consistently failed. The first in 2010 when they attempted to regulate HER2 testing in breast cancer, which laboratories successfully pushed back against due to concerns about delays harming patients and while the medical community has prevailed again, challenges remain, including the need to modernize the 36-year-old Clinical Laboratory Improvement Amendments (CLIA) to address emerging technologies like AI-driven algorithms and whole-genome sequencing. To balance innovation with safety, collaboration rather than top-down regulation is essential, building on existing guidelines for LDT validation pioneered by professional societies like CAP and AMP.