Wisconsin Alumni Research Foundation

Materials & Chemicals
Materials Chemicals
An Orthopedic Implant Coating for Enhanced Bone Growth
WARF: P07031US

Inventors: William Murphy, Jae Sam Lee, Mark Markel, Ben Graf

The Wisconsin Alumni Research Foundation (WARF) is seeking commercial partners interested in developing a biologically active coating for orthopedic implants to enhance bone regeneration.
"Orthobiologics" provides an improved method of treating fractures and other bone defects. This therapy employs inductive molecules, such as bone morphogenetic protein-2 or bone morphogenetic protein-4, to stimulate natural bone growth in defects. The proteins are embedded or adsorbed within collagen sponges, porous ceramic blocks or synthetic polymers and then delivered to the defects.

However, clinical use of orthobiologics technology has been problematic. Carrier materials currently used, such as collagen sponges, to deliver bone growth factors have been inappropriate for orthopedic applications, due at least in part to poor bulk mechanical and degradation properties. Diffusion of growth factors from such carrier materials is not controllable and is released too quickly, leading to rapid degradation in vivo. And new tissue regeneration approaches are not designed to integrate with existing surgical procedures. Improved platforms for delivering inductive molecules in a targeted and controlled fashion are needed before orthobiologics can be widely utilized.
The Invention
UW-Madison researchers have developed a biomaterial-based approach for directing bone regeneration to treat bony defects. This approach uses a biologically active calcium phosphate-based coating to target and control delivery of a bound growth factor molecule capable of inducing bone growth. This coating can be applied to all bioresorbable materials commonly used in orthopedic surgery, including nails, pins, anchors, screws, plates and scaffolds.

Under physiological conditions, the solubility of different calcium phosphate materials can vary by more than 5000 percent. To take advantage of this broad range of dissolution rates, the coating consists of several layers of calcium phosphate materials with distinct dissolution profiles. Bone growth factors are bound to the calcium phosphate and released based on the dissolution profile of each layer. To provide a delayed release, calcium phosphate layers that do not contain a growth factor or drug can be incorporated into the coating. This approach can be easily integrated with existing implants and surgical procedures in clinics.
  • Bioresorbable scaffolds, including arrows, barbs, tacks, bone anchors and other anchors, nails, pins, interference screws and other screws, staples and plates, for the treatment of skeletal defects
Key Benefits
  • Enhances bone growth
  • Provides a customizable coating for controlling drug delivery
  • Materials are readily available.
  • Growth factor is protected from degradation until it is released from the biodegradable coating, resulting in coatings that can last from 12 hours to several months.
  • Integrates with existing implants and surgical procedures
Additional Information
For More Information About the Inventors
For current licensing status, please contact Rafael Diaz at [javascript protected email address] or 608-960-9847