By Nonie Arora
The week of April 13, at the height of cherry blossom season, Duke students traveled to Washington, D.C. to brief senior staff members of the Senate, Food and Drug Administration (FDA), and the Personalized Medicine Coalition (PMC). Over the spring semester, five students in the Genome Sciences & Policy Capstone course (including myself) studied the regulatory framework of laboratory developed tests (LDTs).
LDTs are tests developed for use in a single laboratory. The clinical laboratories that develop LDTs are considered to be medical device manufacturers and are therefore subject to FDA jurisdiction. The FDA exercises “enforcement discretion” over LDTs, which means they choose when to regulate these tests.
Under the supervision of Duke professor Robert Cook-Deegan, we dove into five case studies regarding different types of LDT tests.
The case study that I focused on was the differential regulation of two tests used for breast cancer patients. The two tests, MammaPrint and Oncotype Dx are regulated differently even though both aim to help doctors understand when patients should have follow-up chemotherapy after surgery. The company that markets MammaPrint, Agendia, chose to obtain FDA clearance for their test, but the company behind Oncotype Dx, Genomic Health, chose against it. Surprisingly, this decision did not substantially increase the number of patients who receive Oncotype Dx relative to MammaPrint.
Furthermore, the two tests do not always produce the same result, according to a research study. Several key question remain, such as:
- Is the FDA-regulated test more accurate?
- Does the more accurate test get more market share? Does FDA approval make a difference?
- How should these tests, and ones like them, be regulated to reduce harm to patients?
The students hope that their case studies will serve as illuminating examples for stakeholders and help guide the conversation regarding federal regulation of LDTs.