Nearly 12 million wounds are treated in U.S. emergency departments every year. Skin wounds such as severe burns, large trauma wounds, or non-healing/chronic wounds that are too extensive or complex to close by natural healing are often reconstructed using autologous skin grafts. Although autologous skin grafts are currently the gold standard in complex wound repair, there are significant rates of morbidities, including excessive pain and discomfort, risk of infection, loss of grafted skin, discoloration, scarring, an loss of sensation associated with both the graft and donor sites. This approach is also limited by the availability of healthy skin and is not a viable treatment option for severe burn patients. It s thus imperative to develop alternative treatments for large, full-thickness wounds. Sharklet Technologies, Inc. (STI) proposes to pursue innovative R&D focused on improving the treatment of full-thickness wounds, consistent with the mission of several institutes within the NIH. To overcome the limitations of current dressings and reduce the need for autologous skin grafts, STI proposes to develop an advanced, bilayer wound care dressing comprised of a vasoinductive, biodegradable matrix to promote healing of the dermis combined with a Sharklet micro-patterned apical layer to enhance autologous epidermal healing via guided cell migration into the wound site. Based on our preliminary data and evidence that microtopographies can guide migration of skin cells, we hypothesize that Sharklet micro-patterned surfaces can be optimized to accelerate wound closure through enhanced epithelialization-i.e., coverage by epithelial cells such as keratinocytes. To demonstrate the feasibility of this approach, the following Phase I SBIR Aims are proposed:
AIM I - Demonstrate that Sharklet micro-patterns can increase healing rates in an in vitro model by at least 50% (pd0.05), relative to a smooth standard;
and AIM II -Prove that Sharklet micro-patterned dressings reduce healing time by at least 25% (pd0.05) in a bipedicle ischemic rat skin flap model. The rat model we are using allows us to validate healing behavior for a broad range of non-healing/chronic wounds. Phase I success will lead to a larger Phase II SBIR project focused on validating and extending Phase I results into a porcine model that more closely mimics the healing of human skin. Phase II would also include optimization of manufacturing processes to produce the Sharklet-patterned prototype wound dressings. Phase II will be designed to provide the data needed to engage one or more Phase III commercialization partners by demonstrating the potential to develop an innovative product that uses proven and proprietary Sharklet micro- topographies to accelerate autologous wound healing. Phase III financial and industry partners will participate in and support follow-on clinical trials and commercialization. STI has demonstrated experience in commercializing SBIR-funded innovations via previous Phase III collaborations.
The U.S. annual estimated cost of treating severe and chronic wounds is ~$25 billion. When wound healing is problematic, patches of healthy skin from other areas on the patient are often used to reconstruct the wounded area, but this grafting may lead to severe pain and discomfort at the donor sites, risk of infection, graft rejection, scarring and/r discoloration. Sharklet Technologies therefore proposes in this SBIR project to prove the feasibility of developing micropatterned, bilayer wound dressings that will significantly enhance healing of full-thickness wounds by directing migration of skin cells and new blood vessels into the wounded area and reducing the need for autologous skin grafting.