As of May 30, the FDA has declined to appeal to the District Court for the Eastern District of Texas’s decision to vacate the FDA Laboratory Developed Test (LDT) Rule. This ruling reverts laboratories to the status quo with development and use of LTDs to support patient care and clinical trials. Here we share a brief overview of the ruling and its impact on Discovery Life Science’s business.
The FDA’s decision to regulate LDTs has been controversial from the start, given that LDTs were up to that point considered to be regulated by the Centers for Medicare and Medicaid Services (CMS) under the Clinical Laboratory Improvement Amendments of 1988 (CLIA) framework. Since that date, the FDA has historically looked to assert more control over LDTs and has stated this intent through various publications starting in the 1990s (see here, here, and here). This intent was brought forward through a legislative route via the 2022 Verifying Accurate, Leading-edge IVCT Diagnostic Act (VALID), which effectively codified the FDA oversight of LDTs. The VALID Act was not passed after extensive and effective lobbying by clinical laboratories, hospitals, and patient groups.
At this point, the FDA instead looked to claim regulatory oversight of LTDs in the absence of congressional authorization through a Final Rule, codifying LTDs as medical devices subject to FDA regulation. The Final Rule was first issued on October 3, 2023 and finalized on April 29,2024. Multiple plaintiffs, including the Association for Molecular Pathology and he American Clinical Laboratory Association, sued claiming the FDA exceeded its regulatory authority.
Concerns included jeopardized patient care, reduced innovation, increased costs and administrative burden on laboratories that are already struggling with limited reimbursement. On March 31, 2025, a federal judge ruled in favor of all plaintiffs and vacated the Final Rule. The court ruled that the FDA lacked statutory authority to regulate LDTs under current medical device frameworks. The FDA’s decision not to appeal the ruling by May 30th means the LDT Rule is effectively dead, and any further regulation will require either congressional action or a new approach by the agency.
So, what is the impact to Discovery Life Sciences? On balance, this will not significantly impact the way in which we approach clinical trials. As an organization, we extensively use LDTs to support global clinical trials and have been doing so since the inception of the organization. This approach allows Discovery to get novel clinical trial assays ready for human clinical studies quickly and cost-effectively, a unique combination important to many of our clients (see here).
Foremost, the LDT rule had extensive new requirements for compliance with adverse event reporting and compliance with investigational use requirements (21 CFR Part 812). Because Discovery has been supporting specialty laboratory testing for clinical trials for close to 20 years, our quality systems were already built to comply with FDA requirements (and EU IVDR requirements) regarding pharmacovigilance and SAE reporting.
Furthermore, because Discovery Laboratory Services supports clinical trials almost exclusively, we have historically complied with investigational use requirements, especially with regards to investigational device exemption (IDE) studies. We generate data that is ultimately submitted to the FDA to support drug marketing applications, and we want to ensure compliance with FDA requirements should there be any audits of our facility. Overall, we do not treat any LDTs that we develop as exempt from 21 CFR Part 812 requirements. Lastly, had the rule passed, design controls would have been required for all LDTs we develop. This would have been a significant change to our process for developing novel assays.
While our LDTs are vigorously validated and require change control through our quality management system (QMS), the addition of formal design controls can easily add several months to development timelines and significantly increase the price of assay development and deployment. Our QMS, however, which is ISO13485-compliant, can already support the addition of design controls if warranted. We would typically reserve this approach for investigational devices that are deemed significant risk and used in a pivotal trial (whereas the majority of LDTs we deploy for clinical trials tend to be for early-phase clinical development).
On balance, our work with LDTs to support US-based clinical trials continues without any significant changes to our operations and quality systems for US-based studies. Compliance with IVDR in Europe, however, continues to keep us busy. Look for posts on this topic in the future.