An advanced dermal regeneration scaffold for skin loss due to burn wounds

ABSTRACT The gold standard treatment for large full thickness skin loss (FTSL) due to burns involves autologous tissue transfer in which the patient serves as their own donor. However, such treatment may be challenging due to limited availability of full thickness skin donor sites; thus most of these wounds are closed using split thickness skin grafts (STSG), which contain only a fraction of the native dermal thickness, leading to suboptimal functional outcomes. Dermal Replacement Scaffolds (DRS) aim to recreate dermis, thereby restoring normal skin anatomy. These cell-free products serve as a scaffold for the infiltration of cells from the wound bed that organize to a functional, vascularized neodermis tissue, able to support a STSG. The critical barrier to progress in this field is to create a scaffold that 1) promotes rapid cellular infiltration and angiogenesis required for neodermis formation in full thickness wounds, and 2) increases the efficiency and quality of healing in acute large burns. To address this significant clinical gap, Fesarius Therapeutics, Inc. has developed DermiSphere™, an innovative DRS product that will regenerate dermis in full thickness skin loss wounds significantly and meaningfully faster (≤7 days) than the regeneration achieved using the market-leading DRS product, Integra® (14-28 days). Our customer interview process has revealed additional requirements from a DRS that are currently unmet/partially met: (1) ability to close the wound in a single procedure (2) ability to temporize the wound, (3) ability to close difficult to heal wounds. Our preliminary data have demonstrated in a swine model of FTSL that DermiSphere, unlike any other commercially available DRS, successfully supports complete STSG take when the two components are applied simultaneously. In addition, a small animal model of FTSL showed that DermiSphere supported rapid and sustained lateral as well as vertical cell invasion, resulting in successful STSG “take” in challenging cases of wound beds with avascular portions. A remaining challenge in acute burn wounds, unlike other causes of FTSL, is that simultaneous grafting is often not feasible. Adding a protective layer that can be removed when it is clinically feasible to perform the graft, days to weeks later, will significantly improve the clinical utility of DermiSphere and improve wound healing. Once dermis has regenerated it can be covered with a thin skin autograft, yielding skin that is more flexible, functional, resilient and aesthetically superior than wounds healed with Integra or STSG alone. Given the successful completion of these preliminary studies, DermiSphere is now primed to expand its indication into challenging full thickness wounds such as burns to expand the scope of product use. The overall goal of this SBIR Phase I proposal is to demonstrate feasibility of DermiSphere as a device for the management of acute major burn wounds. The data generated in these studies will directly inform Phase II development work including conducting powered animal efficacy studies. The resulting commercialization will significantly improve clinical outcomes, decrease the number of reconstructive procedures necessary, and reduce patient suffering and costs.