Wendy Chung’s commentary last month about the FDA’s proposed draft guidance for the regulation of laboratory-developed tests (LDTs) is heavily critical of the agency’s plans. Professor Chung argues that the FDA’s involvement in this space will have two primary negative consequences: it will stifle innovation and it will harm patient care.
But the FDA’s proposal seems designed to address precisely these two consequences. The proposal could improve patient care by collecting, for the first time, clinical validity data on tens of thousands of LDTs in current use. And by using an extensive system of carve-outs, the FDA is seeking to minimize potential harms for diagnostic innovation. Understanding these key portions of the FDA’s disclosure to Congress is critical to a full policy discussion of the situation.
The Importance of Clinical Validity Data for Patient Care
Imagine that you are a woman with an extensive familial history of breast cancer. You worry that you may have inherited a genetic mutation in one of your BRCA genes, and you would like to obtain a genetic test to determine that fact. The only commercial provider of such tests advertises a test for 10 possible mutations in those genes. You can be sure that the test accurately detects the presence or absence of those 10 mutations. This is because (as Professor Chung notes) all laboratory testing in the United States is currently regulated by the Clinical Laboratory Improvement Amendments (CLIA), under the auspices of the Center for Medicare and Medicaid Services (CMS).
But here’s the problem: because CLIA only tests for analytical validity, you can’t be sure that the test has any clinical validity at all.
The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.