The Food & Drug Administration said ReGen Biologics Inc. (OTC:RGBO) failed to produce adequate evidence that its Menaflex knee implant was safe before it was cleared to hit the market in late 2008.
Documents released by the federal watchdog agency question whether the Hackensack, N.J.-based company supplied enough data on pre-clinical mechanical testing of the device, which is designed to repair damage to the meniscus cartilage in the knee. The documents also question ReGen’s claims that the device is similar enough to other devices for shoulder, bladder and hernia repair to merit the FDA’s fast-track 510(k) clearance process.
The Menaflex 510(k) clearance in December 2008 came despite the fact that the device often failed and required second operations — and over the objections of FDA scientists who opposed clearing the device. In September 2009 the agency admitted that undue influence from four New Jersey congressmen and former commissioner Andrew von Eschenbach affected the decision to green-light the device and announced an investigation into the foofaraw.
Earlier this month, the agency said a special panel would convene March 23 to review the clearance process for the Menaflex implant, taking a close look at the materials provided by ReGen in its 510(k) application. The documents (PDF) released March 19 question ReGen’s assertion that Menaflex is substantially equivalent to Johnson & Johnson’s (NYSE:JNJ) DePuy Orthopaedics Restore implant for repairing the shoulder joint and to the OrthoMend soft tissue repair matrix made by Boston-based TEI Biosciences Inc. and sold by Stryker Corp.’s (NYSE:SYK) orthopedics arm.
"[ReGen] provided pre-clinical mechanical testing of the [Menaflex] device in comparison to predicate surgical meshes. However, results cannot be directly compared between devices since the listed predicates are indicated for different biomechanical environments," according to the documents. "For tensile strength specifically, [ReGen] did not convert their force results to stresses making it impossible to compare to meniscal stresses reported in the literature. If it is necessary to compare the tensile strengths between devices, the [Menaflex] device withstands substantially less force prior to failure in comparison to the Restore and TissueMend devices (predicates that the sponsor stated are biomechanically comparable). In addition, based on the sponsor’s [Menaflex] device testing, it appears that the failure stress is significantly lower than the estimated circumferential stresses in native meniscal tissue.
"Based on the data provided, it is very difficult to accurately compare the magnitude of tensile stresses on the [Menaflex] device in the knee with that of shoulder surgical meshes. In addition, the cited predicate devices for the shoulder are not intended to be significant load-bearing structures in the shoulder, since the sutures and suture anchors that re-attach tissue to the bone may serve as the source of mechanical strength for the repair rather than the mesh itself serving as such source.
"Overall, the FDA believes that sponsor did not provide adequate pre-clinical mechanical testing data to clearly demonstrate safety against mechanical failure of the [Menaflex] device. The sponsor has provided clinical data, which must also be considered to demonstrate safety against mechanical failure of the [Menaflex] device."
ReGen chairman and CEO Gerald Bisbee Jr. has insisted that the Menaflex is safe and denies many of the allegations made by the FDA.