Biomedical Engineering Reference
In-Depth Information
98 CHAPTER 5. FUTUREDIRECTIONS
and necessary.” While criteria for “reasonable and necessary” are ill-defined, it is clear that the
FDA's mandate of “safe and effective” is not sufficient in warranting reimbursement. Criteria for
reimbursement by private insurers differ from company to company. While it is clear that a need for
long-term cartilage resurfacing exists, whether tissue engineering will be a profitable technology in
addressing this void will depend on many factors.
5.5.3 CURRENTLY AVAILABLE PRODUCTS
While articular cartilage tissue engineered products are currently not available in the US, several
products available in Europe and others that are undergoing clinical trials in the US can serve as
models to inform those seeking to develop and market tissue engineered articular cartilage. Regu-
latory processes in Europe are different from the US FDA, and are reviewed elsewhere [
839
,
840
].
Engineered cartilage employing allogeneic cells may find commonalities with tissue explant allo-
grafts. For lesions greater than 2 cm, Regeneration Technologies has fresh-stored osteochondral
allografts that are cleaned, processed, and preserved with maintained chondrocyte viability. A pro-
prietary antibiotic soak and 14 days of culture monitoring (with 28 days of fungal culture monitoring)
prepare the allografts for implantation [
841
].
Several examples of cartilage treatments using only a biomaterial are available as products.
Trufit (Smith & Nephew) is a product based on biodegradable polymers and used world-wide. Other
products in use include Gelrin by Regentis Biomaterials, a fibrin/polyethylene glycol hydrogel that
can be cross-linked
in situ
for cartilage defects. BioPoly RS, a subsidiary of Schwartz Biomedical,
developed the BioPoly RS (ReSurfacing) device, which is a hydrophilic polymer. SaluMedica has
SaluCartilage, which is a hydrogel that can be used for cartilage damage with CE Mark approval
in Europe but not FDA approval. BST-CarGel, by BioSyntech, is another product with CE Mark
approval and is used for focal cartilage lesions. Results from clinical data on 40 subjects enrolled
in a Canadian-European trial using BST-CarGel are currently being analyzed, and final clinical
results from an 80-patient study using this product are anticipated in 2010. Kensey Nash is in a late
pre-clinical study of an implant, composed of several biomaterials and a biologically active protein,
for osteochondral defects.
Cell seeded scaffolds have also been approved for use in Europe. CaReS (Cartilage Regenera-
tion System) by Arthro Kinetics, uses articular chondrocytes for transplantation. Arthro Kinetics also
developed CartiPlug, which is an acellular collagen matrix for the same indication, and is currently
developing CaReS Plus, which would contain cells for larger cartilage defects. BioTissue Tech-
nologies has BioSeed-C, an autologous 3D chondrocyte graft. Since December 2001 BioSeed-C
started on controlled trials in selected clinics. A four-year follow up study has recently been released
showing stability of the regenerated tissue [
750
]. CellGenix markets CartiGro, which is autologous
chondrocytes combined with Chondro-Gide collagen membrane (from Geistlick Biomaterials),
and is distributed in Europe by Stryker EMEA. Fidia developed Hyalograft C, which uses Hyaff, a
hyaluronic acid derivative, and autologous chondrocytes. DePuy's Cartilage Autograft Implantation
System (CAIS) will harvest, seed onto a biomaterial, and implant the product all in one surgical pro-
