Sometime this year, the U.S. Food and Drug Administration is expected to issue guidance to clinical laboratories that produce lab-developed tests (LDTs). Clinical labs that offer LDTs, and associations that represent these labs, have criticized the FDA’s oversight proposal and are challenging the agency’s authority to regulate these tests.
Many of us will be writing about LDTs, their value to patients and the need for a review of how these tests are produced, whether the results are clinically valid, and whether their marketing claims are accurate.
For journalists needing resources to cover this complex topic, several recent articles and reports serve as good introductions to LDTs. In October 2014, the FDA explained why it proposes to regulate LDTs this report, Framework for Regulatory Oversight of Laboratory Developed Tests (pdf). FDA defines an LDT as “an in vitro diagnostic test that is intended for clinical use and designed, manufactured and used within a single laboratory.”
For an in-depth view of LDTs in particular and clinical labs in general, check out the one-hour video “Medical Tests: Inaccuracies, Risks and the Public’s Health,” that the Boston Globe’s Stat website produced from a webcast earlier this month in cooperation with the Harvard T.H. Chan School of Public Health. The moderator is Sharon Begley, a senior science writer at Stat.
In the video, the FDA’s director of the Office of In Vitro Diagnostics and Radiological Health, Alberto Gutierrez, PhD, explains why the FDA has proposed to regulate LDTs. In the 1970s, pathologists in hospitals and academic medical centers worked closely with treating physicians to develop discrete tests for individual patients. The FDA at the time decided not to regulate those tests, Gutierrez said, but over time became concerned as labs exploited this lack of oversight and sold LDTs nationwide, making what the agency considered unsupported marketing claims for these tests. What’s more, the pathologists who developed LDTs were no long part of patient-care teams, he added.
Gutierrez also explains why the FDA in November issued, “The Public Health Evidence for FDA Oversight of Laboratory Developed Tests: 20 Case Studies.” The 39-page report provides evidence the FDA has collected about LDTs, lays out the agency’s arguments for the need for oversight.
The argument for better oversight of LDTs is the need to evaluate performance of these tests and regulate them as the FDA does with medical devices, Gutierrez said, adding that FDA also wants to evaluate the premarket claims made about the tests.
A number of journalists have done in-depth reporting on LDTs. Two in particular stand out. Thomas Burton of The Wall Street Journal recently explained how LDTs are the wild west of medicine. Burton reports that the Center for Responsive Politics shows that one lab-industry trade group has spent more than $1.6 million since last year to lobby lawmakers about LDTs.
Arielle DuHaime-Ross, a science writer at The Verge, has written a thorough explanation of the LDT controversy as well. She cited examples of three clinical labs that have produced LDTs for cancer and yet adds that none of the companies has published data at the tests in peer-reviewed journals.