Letter to Dr. Margaret Hamburg on the De Novo Process and High Risk Medical Devices

February 29, 2012

Dear Commissioner Hamburg,

We are writing as members of the Patient, Consumer, and Public Health Coalition to express our concerns about the use of the de novo process for high-risk medical devices.

We have previously expressed our strong concerns about the low standards of the 510(k) premarket clearance process for medical devices. Although intended for low- and moderate-risk devices, too many devices that are high-risk are cleared through the 510(k) process and later found to cause life-threatening adverse events.

The law requires that class III medical devices for which general and special controls cannot provide reasonable assurance of safety and effectiveness be reviewed through the premarket approval (PMA) process. The Food and Drug Administration (FDA) defines Class III devices as those that “sustain or support life, are implanted, or present potential unreasonable risk of illness or injury. Nevertheless, we have documented numerous examples where such devices were reviewed under the less stringent 510(k) process.

Very few devices go through the de novo process, which is intended for moderate-risk devices found to be not substantially equivalent to a device that was introduced or delivered for introduction into interstate commerce for commercial distribution before May 28, 1976, or to a device which was subsequently reclassified into class I or class II.

We agree with the Institute of Medicine that the de novo process makes more sense than the 510(k) process for some moderate-risk devices.​

However, the Center for Devices and Radiological Health has announced its approval under the de novo process of an endovascular suturing system “used in patients whose endovascular grafts have exhibited migration or endoleak, or are at risk of such complications, in whom augmented radial fixation and/or sealing is required to regain or maintain adequate aneurysm exclusion.”The endovascular suturing system, which was categorized as a class III device and is intended for the repair of aortic endografts, is obviously a permanent implantable device that is intended for a life-sustaining purpose, for which general and special controls would not provide reasonable assurance of safety and effectiveness. It is a clear example of a medical device that should be reviewed under the PMA process. It is not in the interests of public health that the FDA is planning to reclassify this product as class II through the de novo process, thus bypassing the PMA process. While the “special controls” applied through the de novo process are more rigorous than the standards for clearance through the 510(k) process, they are considerably less stringent than the PMA process and fail to provide a reasonable assurance of the safety and effectiveness of this high-risk device.

Finally, we note that the limited clinical testing of the endovascular suturing system was inadequate to prove the safety or efficacy of this implanted device for most patients, since it included only 10 women (and 144 men), no comparison control group, and only one year of follow-up. (No information about racial or ethnic diversity is publicly available.)

Therefore, we urge the FDA to rescind its final rule (21 CFR Part 870) classifying the endovascular suturing system into class II (special controls) and instead require a PMA application for this device with more rigorous clinical testing. In addition, we ask that you provide an explanation of how these devices, which repair an aortic endograft, do not satisfy the criteria that the FDA sets for high-risk devices that they “sustain or support life, are implanted, or present potential unreasonable risk of illness or injury” if it were to fail.

Thank you for considering our comments and responding to our inquiry in this very important matter.

American Medical Women’s Association
Center for Medical Consumers
Community Access National Network
Consumers Union
Jacobs Institute of Women’ Health
National Consumers League
National Research Center for Women & Families / Cancer Prevention and Treatment Fund
National Women’s Health Network
Our Bodies Ourselves
Public Citizen