The FDA’s Approval of ProteGen Baffles the Mind
Posted by
Armand RossettiDecember 19, 2008 2:21 PM
Supple Peri-Guard was being used for the “repair of hernias and other intra-abdominal soft tissue defect or deficiency." However, Peri-Guard was not a true synthetic mesh.
patient’s own fascia or muscle to support periurethral tissue (autologous tissue graft), but that method was very invasive, and surgeons turned to using synthetic materials.
DePuy, Inc., submitted a 510(k) for its surgical mesh and listed equivalent devices, including Peri-Guard. In reviewing the DePuy 510(k), it is evident that Peri-Guard was manufactured from “SIS porcine small intestine submucosa,” and that surgeons had been using Peri-Guard for hernia repair, wound dressing, and as a mesh sling (the mesh is similar to this depiction of cross-linked porcine collagen).
caused an erosion rate that was 15 times that of natural slings that were either autologous (tissue taken from the same person), an allograft (human tissue taken from another person), or a xenograft (tissue taken from another species).
“…intended to reinforce soft tissue where weakness exists for the urological, gynecological and gastroenterological anatomy inclusive but not limited to the following procedures: pubourethral support, urethral and vaginal prolapse repair, colon and rectal prolapse repair, reconstruction of the pelvic floor, bladder support, and sacro-colposuspension.”
to view the entire patent, click on “Save Full Document”). Surgeons would use a drill guide to bore into either side of the pubic bone and then insert a left and right pin. Those pins were originally attached to suture material that led to either side of the urethra to support a “Bladder Neck Suspension” procedure. Boston Scientific later included the ProteGen sling as part of the Vesica System. The reason that Boston Scientific combined the two devices was due in part to corporate acquisitions, and ccertainly not because of extensive research.
Boston Scientific Corporation acquired Vesica and the Vesica System. Boston Scientific Corporation also acquired Meadox Medicals, Inc., which manufactured a bovine collagen covered polyester fabric called Hemashield, and that fabric was a tubular graft used in cardiovascular applications.
multicenter longitudinal study, (5 centers) investigators examined the records of patients who had ProteGen slings removed. Of the 34 patient records examined, 7 patients had isolated urethral erosion, 17 had vaginal extrusion, and 6 were associated with urethrovaginal fistulas (openings between two organs that usually do not connect). All of those slings required removal.
Surprisingly, however, materials experts in the medical arts have known, for decades, the reasons why different sling materials behave in specific ways.
dense inflammatory reaction. The previous linked figure depicts a strip of Mersilene (“filet de Mersilene”) with interspersed collagen fibers (“fibres de collagene”), giant cells (“cellule de geante”), and neutrophils (“polynucleaires”), which are all suggestive of ongoing inflammation.
in vitro and in vivo premarket studies. Third, everyone involved in producing sling devices should pay more attention to reviewing any and all available information about the chemical and physical makeup of materials destined to become a part of the device. Lastly, the FDA should take more time to investigate the compositions of all listed predicate devices and to determine whether or not those devices are actually "substantially similar" to the devices for which manufacturers are seeking approval.