The US Food and Drug Administration (FDA) has announced that it will begin to actively monitor medical laboratory testing. The aim of the regulation is to ensure efficacy and safety of lab tests which are used by physicians to make important treatment decisions.

The FDA stated that it would scrutinize laboratory developed tests (LDTs) where a wrong result would pose the highest level of risk to patients. LDTs are in vitro diagnostics in which human samples are sent to and tested at a central, typically single-site, laboratory. The FDA will exempt tests for which there are no approved alternative and tests for rare diseases which could cost more to develop if they need an FDA review.

Medical Laboratory Testing

BRCA gene tests for breast and ovarian cancer risk and tests for the detection of Lyme disease are examples of high-profile LDTs. According to Jeffrey Shuren, MD, JD, director of the Center for Devices and Radiological Health at the FDA, LDTs could result in unnecessary treatment for various conditions such as heart disease, cancer, and infections. FDA premarket review would determine if such tests are accurate, reliable, and clinically meaningful.

Justifying the regulation, FDA commissioner Dr. Margaret A. Hamburg said, “Just as drugs need to be safe and effective for treating diseases, medical devices used to help diagnose disease and direct therapy also need to be safe and effective”.

Decision draws praise, flak

The FDA’s decision to regulate LDTs has drawn praise and flak.

The American Association for Cancer Research has welcomed the Framework for Regulatory Oversight of Laboratory Developed Tests as a “key step” to advancing personalized medicine. Some medical societies and patient advocacy groups have also hailed the move saying that it will provide “real value” to the clinical community. Currently, clinicians usually decide whether an LDT is useful to them or not based on trial and error. With the FDA’s oversight, clinicians will know sooner if a particular test technology is not working, is malfunctioning, or is not properly designed.

However, the American Medical Association (AMA) believes the FDA’s additional regulatory requirements will result in patients “losing access to timely lifesaving diagnostic services and hinder advancements in the practice of medicine”. Laboratories, pathologists and some testing companies also feel that the need to obtain FDA approval will discourage innovation. Lab tests can be developed more rapidly and changed quickly based on new information if FDA approval is not required.

Risk-based Regulatory Framework

The proposed regulatory framework is “risk based”, according to the FDA. The agency said that LDTs have avoided its scrutiny in the past because the in vitro diagnostics that laboratories manufactured were relatively simple, low-risk, well-understood tests for rare diseases for which adequate validation would not be feasible. However, the marketplace has dramatically changed and many new complex tests and tests are being developed with a higher level of “risk” involved for patients, leading the FDA to decide that tests used to make treatment decisions must validated before they are used.

Factors that the FDA will consider when determining the risk an LDT poses to a patient include whether or not the device is meant for use in high-risk disease, such as cancer, or for screening or diagnosis, and also the nature of the clinical decision that will be made based on the test results.