Citing a growing body of evidence suggesting that a small number of patients may have biological responses to certain types of materials in implantable or insertable devices, FDA is calling on the public, scientists and industry stakeholders to gather information and help it determine the current state of the science. The agency is seeking to identify critical gaps in the existing science that need to be addressed and further its understanding of medical device materials to improve the safety of devices for patients.
The symptoms some patients experience may be limited to the region where the device is implanted or may be more generalized, notes the statement from FDA Commissioner Scott Gottlieb, MD, and Jeff Shuren, MD, Director of the Center for Devices and Radiological Health. “Symptoms include but are not limited to fatigue, rash, joint and muscle pain or weakness. Although uncommon and varied, these symptoms may share common underlying immune/inflammatory pathways and mimic more well-established inflammatory conditions,” they write.
The statement, which was distributed on March 15, went on to say that “in the small subsets of patients who have reported these symptoms, the symptoms may not develop for several years following implantation. As a result, they may not be detected even in larger and longer clinical studies. To date, these symptoms have not been reported with most materials used in medical devices, including most metals. Moreover, when reported, they have tended to be limited to small subsets of patients.”
Stressing that the vast majority of patients implanted with medical devices have no adverse reactions, the statement called out silicone breast implants, metal implantables, animal-derived materials, nitinol-based devices, including the Essure birth control device, which has been pulled from the market, and metal-on-metal hip implants as worthy of additional scrutiny.
There are currently no FDA-approved metal-on-metal total hip replacement devices marketed for use in the United States. However, the agency said that it is working with standards development organizations to develop new standards to improve how these devices are evaluated and to identify additional testing protocols for new metal-on-metal devices that are submitted for review.
FDA also announced that it would hold an advisory committee meeting in the fall to discuss metal implants and the potential risk for certain patients to have “hypersensitivity” or exaggerated immune and inflammatory reactions to these metals.