Decoding the Diagnosis: a Look at LDT Regulations and the FDA’s Stance

Laboratory Developed Tests (LDTs) play a vital role in modern medicine, aiding in diagnosis and treatment decisions. However, the regulatory landscape surrounding LDTs has been a topic of debate for years. The FDA, responsible for ensuring the safety and effectiveness of medical devices, has historically exercised enforcement discretion for most LDTs. This essentially meant they haven’t enforced the same regulations as for other diagnostics, and other agencies (e.g. CMS, CLIA) have been considered as potentially appropriate authorities for effective oversight  

This approach is changing. In May 2024, the FDA finalized a new rule that would increase oversight of LDTs.  The rule would go into effect on May 6, 2025, although there is a roll out period. In addition, there are certain exemptions written into the rule. Let’s explore the current situation and the FDA’s position on managing risk and oversight of LDTs. 

What Exactly is an LDT? 

A laboratory developed test, or LDT, is a diagnostic test designed, manufactured, and used within a single specific laboratory. These tests analyze samples like blood, tissue, or saliva to diagnose or monitor medical conditions. LDTs differ from commercially available tests in that they are not sold or distributed to other labs.  

The Rationale for Change 

The FDA argues that increased oversight is necessary to ensure the safety and effectiveness of all diagnostic tests, including LDTs. They point to concerns about the potential for inaccurate results with some LDTs, which could lead to misdiagnosis and improper treatment. Additionally, the lack of standardized regulations creates an uneven playing field for LDT developers compared to commercially available diagnostics. 

What the Rule Means 

The rule aims to bring LDTs under the umbrella of FDA regulations for In Vitro Diagnostics (IVDs). This would mean LDT developers would need to comply with various requirements, potentially including: 

  • Premarket review: Submitting data demonstrating the test’s safety and effectiveness. 
  • Quality system requirements: Implementing procedures to ensure consistent test quality. 
  • Adverse event reporting: Reporting any serious problems encountered with the test. 

The Future of LDT Regulation 

The rule has sparked debate within the medical community. Some stakeholders support the FDA’s efforts to ensure safety and fairness. Others worry about the potential impact on access to innovative LDTs, particularly those developed by smaller laboratories. 

The FDA’s Position: Balancing Safety and Innovation 

The FDA acknowledges the concerns raised and emphasizes their commitment to a phased-in approach for implementing the new regulations. This aims to minimize disruption to the healthcare system while ensuring patient safety. They also plan to create different regulatory pathways tailored to the complexity and risk profile of LDTs. 

What’s Next? 

It’s important to stay informed about the evolving regulations to understand the potential impact on how LDTs are developed, used, and accessed.  However, there are professional organizations that are individually and collectively pushing back against the final rule. For example, the American Clinical Laboratory Association (ACLA) has filed lawsuit which disputes the FDA’s authority to regulate LDTs. Rather, if one considers an LDT a professional service vs a manufactured device, oversight should fall under Centers for Medicare & Medicaid Services via the Clinical Laboratory Improvement Amendments (CLIA). In addition, members of Congress have introduced Congressional Review Act resolutions to repeal the FDA’s final rule on LDTs. It remains to be seen if these efforts will be successful.   

How HcFocus Can Assist 

HcFocus provides an integrated approach to market access. Certainly, while it remains unclear when or even if the new rule will take effect, a team approach that encompasses and aligns both regulatory and reimbursement concerns is imperative. Timing is really everything when it comes to the new FDA rule. Understanding potential exemptions may be most relevant. While for other companies, although potentially burdensome, complying with the new FDA rule may give our clients another opportunity to highlight the patient benefits of their tests and smooth the path to reimbursement. 


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FDA: Laboratory Developed Tests

American College of Medical Genetics and Genomics (ACMG): Laboratory Developed Tests (LDTs) and Additional Resources

American Clinical Laboratory Association (ACLA): LDT Rule Override Takes Center Stage as ACLA, Congress Seek to Undo Rule