The US Food and Drug Administration (FDA) has announced it would revoke its previous approval for a collagen-based knee implant called Menaflex after meeting with its manufacturers, ReGen Biologics.
The approval had been granted under the 510(k) process which only requires that a manufacturer demonstrate that its device is "substantially equivalent" to one or more products already cleared for marketing. First-in-class products require a more stringent premarket approval (PMA) process, for which full efficacy and safety trials must be conducted.
The FDA has now concluded that the 510(k) process was inappropriate in this case because Menaflex "is intended to be used for different purposes and is technologically dissimilar from devices already on the market."
The agency also cited findings from its internal investigation suggesting that "external pressures" had influenced the device's review.
Menaflex is a crescent-shaped piece of resorbable collagen-based material, something that can dissolve and assimilate such things as bone tissue. The device meant or patients with medial meniscus injuries is surgically implanted. ReGen Biologics say the product is intended to provide a scaffold for new meniscal tissue to grow.
Before beginning the revocation process, the agency indicated that it would seek a meeting with ReGen officials to discuss the appropriate marketing pathway for the device and what data the company would need to present to provide a reasonable assurance of safety and effectiveness.
The company could theoretically get the product cleared again by going through the full PMA process.
ReGen issued a statement indicating that "the company is currently weighing its options." It also asserted that "there has never been a safety issue" with the product.
In justifying its decision to yank Menaflex's 510(k) clearance, the FDA cited findings from its internal investigation that were released in September 2009, indicating that "external pressures" had affected the product's review.
The investigators found evidence that in 2008 ReGen had lobbied FDA commissioner Andrew von Eschenbach, MD, on behalf of Menaflex, such that he became "personally engaged in the details of a process usually coordinated at the Center level."
According to their report, von Eschenbach ordered the CDRH's director at the time, Daniel Schultz, MD, to convene a review panel meeting for Menaflex on short notice, the result being that several experienced members could not attend and materials were made available one week before the meeting instead of the usual three to five weeks.
The report also noted that the commissioner showed "unusual interest in the composition of the panel," asking to see their resumes, and "pressed the Center to issue a decision" shortly after the panel's November meeting, as did the company.
The center's staff had initially determined that Menaflex was not substantially equivalent to existing approved devices and hence ineligible for 510(k) approval. But Schultz ordered a reconsideration of that determination, which was subsequently reversed.
Under pressure from ReGen, FDA staff who had participated in the original negative review were not allowed to speak at the panel meeting, according to the investigation report.
Schultz resigned in August 2009 following allegations from some CDRH professional staff that they had been pressured by senior officials to reverse negative device evaluations.
In deciding to revoke Menaflex's clearance, the FDA also relied on input from its Orthopedic Devices Advisory Committee, which met this past March to review the scientific data on the product.
The panel expressed few concerns about the product's safety, but indicated that the evidence for its effectiveness fell short in some areas.