In this week’s New England Journal of Medicine, 359 NEJM 88 (July 3, 2008), the FDA responds in a letter to harsh criticism published in the Journal earlier this year on the issue of medical device approval. Dr. Daniel Schultz expresses concern “about several statements” in the earlier article that “may have misled readers.”  Readers of MassTortDefense know that significant product liability litigation has arisen over recalled medical devices in recent years.

In the earlier “Perspective,” Dr. William H. Maisel criticized the FDA’s decision to approve a device (an implantable cardioverter–defibrillator (ICD) lead) in 2004. See Maisel WH., “Semper fidelis — consumer protection for patients with implanted medical devices,” 358 NEJM 985 (2008). Dr. Maisel is apparently a consultant for the FDA and a member of the Medicare Coverage Advisory Committee.

Obviously, no complex device can be 100% free of design, manufacturing, and performance flaws. Malfunctions inevitably occur, and manufacturers should be rewarded, not criticized, for identifying and correcting any problems. The demands placed on ICD leads, in particular, are intense: they must withstand hundreds of millions of repetitive cardiac cycles, survive in the hostile environment of the human body, and allow delivery of high-voltage energy at a moment’s notice. A recent editorial in the Wall Street Journal opined that “the real danger to public health is the overreaction to medical risk,” noting that some patients refuse to have a device implanted because of concern about potential malfunctions.

Maisel argued, however, that the agency is failing to fulfill its mission of helping the public get the accurate, science-based information they need. Essential consumer protections are currently lacking, allegedly. He argued it was “increasingly apparent” that improvement will require Congressional action.

Specifically, Maisel criticized the FDA for approving changes in the device/lead on the basis of bench testing rather than clinical data. However, FDA regulations allow manufacturers to apply for marketing of a modified device on the basis of bench testing, and many devices are approved in this way. This is not an inherently unsafe approach, Dr. Schultz noted. In evaluating an application involving a modified device, the FDA will analyze the proposed modification, determine the potential types of failure, and tailor testing requirements accordingly. In many cases, agency questions are best answered by performing appropriate engineering analyses, but in other cases, FDA may also require clinical data.  To require that these modified devices undergo clinical trials across the board as a condition of FDA approval would limit the availability of improved products. Also, most of these trials would, in any event, have insufficient power to detect small but clinically meaningful differences in performance.

Maisel also criticized some device manufacturers for continuing to market existing models while modified models await FDA approval. But there is nothing inherently wrong with doing so unless the older models pose undue health risks.