The FDA’s “most stringent” medical device approval process isn’t that stringent after all, researchers at Northwestern University have found.

In their new study, Steve Xu, MD and Jessica Walter, MD reviewed the evidence, or lack thereof, behind 18 recent high-risk medical device approvals, finding glaring flaws in how and why the FDA allows potentially-dangerous medical devices to enter US doctor’s offices.

High-Risk Device Approvals Marred By “Flawed Data”

Each of the 18 products had gone through the FDA’s Pre-Market Approval (PMA) process between 2000 and 2015. PMA is meant to be tough, and only devices that promise either extreme benefit or extreme risk have to undergo this most “rigorous” screening.

FDA Pre-Market Approval Infographic

Rigor, however, isn’t what Xu and Walter found. In fact, Xu, a resident in Dermatology at Northwestern, says that although recent health crises should have put regulators’ focus firmly on public safety, “the evidence leading to approval has a lot of weaknesses.”

Of the 18 high-risk devices studied, all of which were intended to tackle women’s health issues, four were approved despite having failed to meet efficacy goals during clinical trials. In short, the devices didn’t work as their manufacturers had hoped, but that didn’t stop the FDA from allowing their release onto the market.

Even though all of the devices had been deemed “high-risk,” posing, in the FDA’s words, “a potential unreasonable risk of illness or injury,” six were allowed to enter the market without the so-called “post-marketing” studies that allow regulators to monitor evolving safety concerns.

Nearly half, 42%, of the 18 devices were approved solely on the basis of nonrandomized controlled trials, a form of study that can only draw relatively weak conclusions about the safety or efficacy of a medical product.

High-Risk Medical Device Failures Infographic

Lack Of Evidence, With Predictable Results

These aren’t theoretical gaps in an otherwise strong regulatory system.

Three of the devices reviewed by Xu and Walter are no longer on the market, withdrawn, in at least one case over patient safety issues. That particular device, which was apparently too dangerous to use on patients, hadn’t been put under postmarketing surveillance at the time of approval. The other two devices that were pulled had been found ineffective in their pivotal clinical trials, the studies that served as the basis for their approval.

Don’t Listen To The Experts

One of the recalled devices had even failed to meet the standards of the FDA’s own obstetrics and gynecology advisory committee, a panel of practicing experts who review the medical evidence for and against a device’s approval. Advisory committees offer expert opinions and, for at least one of the devices that Xu and Walter looked at, the obstetrics and gynecology board refused to endorse the product.

Medical Device LCD Display

Of course, advisory committees are kind of optional. The FDA doesn’t have to call in the experts if it doesn’t want to. For the other two devices now taken off the market, the FDA never consulted the obstetrics and gynecology advisory committee at all.

Essure, A Case In Point

In a statement released after the study’s publication, Xu and Walter pointed specifically to Essure, the permanent sterilization implant that has become controversial, and something of a lighting rod within the women’s health community, as evidence of the PMA process’ weaknesses.

Essure, now linked to dozens of severe side effects and implicated as the cause of extreme suffering nationwide, was “approved based on short-term evidence and insufficient post-market follow-up,” the researchers say. Now it seems patients are paying the price for that lax oversight.

Essure Approval Criticism Infographic

It’s a problem that goes far beyond Essure, one that could get worse far quicker than it gets better. As Xu points out, the FDA actually has far higher standards when it comes to new drugs, whether or not the pharmaceuticals have been deemed high-risk. Plus, Congress is currently considering a bill, the 21st Century Cures Act, which already passed in the House of Representatives, that would lower medical device approval requirements even further.

That doesn’t make much since, but it’s true, and it’s a truth that forces us to pose an obviously ridiculous question: “should we really be holding high-risk medical devices to a lower standard of evidence than drugs?”


The paper, “Medical Device Approvals Through the Premarket Approval Pathway in Obstetrics and Gynecology from 2000 to 2015: Process and Problems,” was published by the journal Obstetrics and Gynecology on May 4, 2016. An abstract is available here.