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Inside the Lab Regulation and standards

Testing Times

Historically, laboratory developed tests (LDTs) have been unregulated. Now, the FDA has proposed that LDTs should be classed as medical devices and subject to the same standards as other in vitro tests (1).

We asked Mary Steele Williams, Executive Director of the Association for Molecular Pathology (AMP), about the society’s response to the proposal.

What is AMP’s stance on the recent proposal for LDT regulation?

AMP is concerned that the FDA is again trying to overstep its authority and bypass the legislative process in the United States. We are disappointed to see the agency moving forward without first fully understanding the many implications this drastic policy change will have on the practice of medicine and on patients’ access to needed clinical tests.

When AMP met with the White House Office of Information and Regulatory Affairs last month, we asked for the FDA to issue a request for information prior to publishing the proposed rule to better understand its potential harms, specifically the disruption to patient care and laboratory operations at community-based clinics and academic medical centers. 

Do you think the proposal is misguided? And, if so, why?

Yes; if finalized, the proposed rule will impede the ability of clinical laboratories – including many academic medical centers, reference laboratories, and community health systems across the country – to rapidly develop, validate, and offer high-quality, innovative laboratory developed testing procedures (LDPs) for patient care. AMP refers to these services as LDPs instead of LDTs given they are vital procedures performed by qualified medical professionals. 

LDPs are essential testing services that professionals in regulated clinical laboratories develop and use for a range of purposes, including oncology, rare disease diagnosis, newborn screening, infectious disease testing, and more. They are designed, developed, validated, performed, and interpreted by board-certified professionals. LDPs are not commercially manufactured and marketed, nor boxed and shipped as medical devices, and should not be regulated as such. 

The proposed rule threatens the ability of professionals in clinical laboratories to create, adapt, and modify LDPs to meet patients’ needs, account for supply chain issues, reflect advances in scientific understanding and practice standards, and improve performance characteristics.

How have AMP members responded to the proposal?

AMP members are continuing to review the FDA’s proposed rule and assess the full impact on clinical lab practice and patient care. We will submit formal comments by the deadline.

However, our members believe FDA provided insufficient time for stakeholders to adequately respond to the proposed rule. This is why AMP and more than 90 other organizations have requested a 60-day extension to the comment period.

The FDA has said that the proposal is “aimed at helping to ensure safety and effectiveness.” How does AMP respond to this?

The American public saw firsthand how ineffective and inappropriate FDA medical regulations are for LDPs during the early days of the COVID-19 pandemic. FDA enforcement prevented many laboratory professionals from mitigating the flaw in the first test kit provided by the Centers for Disease Control and Prevention. FDA’s implementation of the emergency use authorization process overwhelmed the agency, contributed to testing scarcity, and eliminated the opportunity to immediately contain and slow the spread of this highly transmissible virus in those critical first weeks of the pandemic. 

This same entity should not be responsible for regulating all LDPs for conditions ranging from infectious diseases to cancer. 

Does AMP have an alternative proposal that can help ensure patient safety?

AMP members have spent the past 10 years collaborating with many professional societies, patient advocates, diagnostic companies, hospitals, academic centers, independent laboratories, and other stakeholders from across the country to help educate lawmakers on alternative proposals. 

We have long maintained that the involvement of appropriately trained and qualified laboratory professionals is critical to the development of accurate and reliable LDPs, as well as for correct utilization, precise interpretation, and appropriate application of molecular test results. The AMP proposal modernizes the current Clinical Laboratory Improvement Amendments (CLIA) regulation program and provides assurance of quality, analytical validity, and clinical validity. Our approach would provide a far more appropriate and efficient regulatory framework that ensures access to necessary patient care while continuing to foster rapid innovation and the promise of new diagnostic technologies.

Image Credit: Purple Pipette by Louis Reed sourced from

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  1. FDA, “FDA Proposes Rule Aimed at Helping to Ensure Safety and Effectiveness of Laboratory Developed Tests” (2023). Available at: 
About the Author
Helen Bristow

Combining my dual backgrounds in science and communications to bring you compelling content in your speciality.

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