Lately, you may be hearing a lot about the Food and Drug Administration (FDA) proposed regulation of Laboratory Developed Tests (LDTs). For those who do not work in the lab every day, the strong opinions and abundance of information may be confusing to wade through. What are these LDTs? Why is the FDA choosing to regulate these tests? What is the proposed oversight? In this “just-the-facts” post I will answer all these and give some clarity in a much cluttered topic.

An LDT is defined by the FDA as “a type of in vitro diagnostic test that is designed, manufactured and used within a single laboratory.” LDTs vary in complexity and purpose. Some simple tests can measure levels of sodium present and other more complex tests can be used to detect genetic disorders in an unborn child. Currently, it is estimated that there are over 11,000 tests that fall into this category that receive little to no federal oversight.

The FDA has asserted that LDTs have long been considered “medical devices” under the 1976 Medical Device Amendments to the U.S. Food, Drug and Cosmetic Act (USFDCA). While the FDA used discretion in enforcement of this category for almost 40 years, LDTs have advanced in complexity to the point that potential misinformation generated from these tests poses a significant risk to the patient.

It is important to note, the Centers for Medicare & Medicaid Services (CMS) regulates laboratories, including those that develop LDTs, under the Clinical Laboratory Improvement Amendments (CLIA). While CLIA requirements address the laboratory’s testing processes, they do not assess the clinical validity of the tests being performed. Specifically LDTs do not undergo regulation in the forms of:

  1. Pre-market Safety and Efficacy Data; there is no assurance that a specific LDT provides accurate information or that that information is even clinically relevant.
  2. Quality Manufacturing Data; there are no routine FDA inspections of the manufacturing of LDTs to ensure quality as CLIA only focuses on the laboratory process for using the device.
  3. Medical Device Reporting (MDR); adverse events as result of an LDT do not have to be reported to the FDA, making it difficult to detect and recall devices that are inaccurate or unsafe.

The FDA proposed draft for oversight of LDTs embraces “a risk-based, phased-in approach for oversight to balance maintaining patient access to critical tests, while mitigating risks effectively.” High-risk LDTs will be subject to pre-market clearance, registration and listing, and adverse event reporting while the FDA will continue to use discretion in regards to applicable premarket review and quality systems requirements for “low risk” LDTs.

The FDA proposes to include in the high-risk category LDTs, those that compete with FDA-approved or cleared companion diagnostics currently on the market. The draft guidance also includes the agency’s proposal for the categorization of LDTs that are low- or moderate-risk, which would be subject to registration requirements, in addition to the regulation and document requirement under the CLIA.

The proposed regulations are strongly opposed by many in the laboratory industry including the American Medical Association and the American Clinical Laboratory Association (ACLA) who argue that “another layer of regulation could stifle diagnostic innovation and ultimately jeopardize patient access to timely and effective treatment.”  Proponents of the regulations, led by diagnostic and manufacturing companies argue that this proposed regulation closes a key gap in oversight of laboratory tests. “It is critical to ensure that patients and health care providers have confidence in the accuracy and reliability of tests that may be critical to their health and care, no matter where the tests are made or performed.”