By David Strauss, M.D., Ph.D.
At FDA’s Center for Devices and Radiological Health (CDRH), results from clinical trials often serve as the foundation for our decisions to approve the most important medical devices—devices, such as implantable heart devices, that carry the greatest risk to patients and have the potential to save or sustain life.
While there is risk inherent with all medical devices and procedures, we look for potential gaps in that foundation—gaps that could be filled with more information or data.
One information gap is that there are not enough women enrolled in some clinical trials.
Why is that a gap?
Underrepresentation of women (or minority or ethnic groups) results in a lack of information for these patients and their physicians regarding risks and benefits of some medical products. Certain differences between women and men—including anatomy and physiology—can lead to medical devices performing better or worse.
FDA is actively trying to learn more about how to optimize the safe and effective use of medical devices in women.
With support from FDA’ Office of Women’ Health, CDRH recently performed an analysis of data from multiple clinical trials conducted in support of cardiac resynchronization therapy (CRT), a pacemaker therapy for patients with heart failure. Only 22% of the patients in the clinical trials were women. We combined individual patient data from multiple clinical trials to increase the number of women in the analysis.
We found that women benefit from CRT significantly more than men do. Patients of both sexes with a left bundle branch block (LBBB), an electrical conduction disorder in the heart, benefited most. However, women did so at a shorter QRS duration (time to complete electrical activation of the heart) than men. In the patients with LBBB and shorter QRS duration, women had a 76 percent reduction in heart failure or death, while there was no significant benefit in men. With LBBB and a longer QRS duration, both women and men benefitted from CRT.
We discuss this in greater detail in today’ Journal of American Medical Association: Internal Medicine. It was FDA’ first individual-patient data analysis involving medical devices from multiple companies.
Later this summer, FDA plans to take two additional steps to address this information gap.
One, CDRH intends to finalize a guidance document that provides a clear framework for how to analyze and communicate data on women in medical device clinical trials.
Two, FDA intends to release an Action Plan—mandated by Congress—that contains recommendations for improving the completeness and quality of analyses of data on women, as well as other populations, in summaries of product safety and effectiveness data and in labeling.
As illustrated in today’ publication in JAMA: Internal Medicine, combining individual-patient data from multiple clinical trials is an additional research tool that can help answer questions about patient groups underrepresented in clinical trials—and help us strengthen the foundation for all of medical devices on the market.
David Strauss, M.D., Ph.D. is a medical officer in FDA’ Center for Devices and Radiological Health.