The goal of this Phase I SBIR proposal is to demonstrate the feasibility of an inherently broad- spectrum antimicrobial tissue scaffolding matrix capable of eliminating infecting bacterial pathogens, and improve wound closure in diabetics. Delayed non-healing diabetic wound is responsible for about 100,000 annual non-traumatic lower-limb amputations in the US. Microbial infections further complicate the wound and it has been suggested that pathogenic biofilms play a major role in the prevention of wound healing. The presence of biofilms and the emergence of multi drug resistant organisms (MDROs) have made the current topical and systemic antibiotics becoming progressively less effective to combat diabetic wound infections. While prevention and elimination of pathogens from a diabetic wound is crucial, it is equally important to promote the wound closure by tissue regeneration to reduce the chance of further wound infection. Unfortunately, current products all show limited efficacy in these aspects. G4db, the proposed product overcomes current limitations by both (i) preventing/eliminating infection through a unique mechanism of action that is broad spectrum antibacterial, and (ii) promoting tissue regeneration by providing cell attachment sites within the scaffolding matrix. Unlike any of the products currently used in the clinics, G4db does not rely on using any externally added antibiotics, but rather takes advantage of charge composition to exert toxicity against Gram-positive and -negative bacteria (including antibiotic resistant strains). Furthermore, G4db relies only on sequences for antimicrobial charge ratio, and therefore is cell friendly, non-inflammatory and nontoxic with a structure and pore size very similar to the native extracellular matrix (ECM). To establish feasibility for the treatment of diabetic wound infections, we propose the following two main tasks:
Specific Aim 1) Therapeutic in vivo efficacy of G4db to eliminate infection. Demonstrate the in vivo feasibility of G4db as an antimicrobial that prevents colonization of P. aeruginosa, a common pathogen associated with wound infections.
Specific Aim 2) G4db tissue scaffolding matrix accelerates tissue regeneration. Demonstrate in vivo efficacy of G4db as tissue scaffolding matrix that promotes tissue regeneration in full-thickness dorsal excisional wounds in a diabetic swine model. It is expected that the generated data will provide the necessary information to move the proposed product into commercialization. In SBIR Phase II, we will validate the hydrogel in an infected wound healing swine model, establish GMP manufacturing, and execute GLP studies in preparation for our FDA submission.
For patients with diabetes, every wound is a serious health concern and requires immediate attention to prevent infection and becoming recalcitrant non-healing ulcers. Current treatment strategy involving the use of antibiotics is becoming less effective due to increased incidence of antibacterial resistance. In light of this, we propose to develop safe and easy-to-use wound care dressing substitute that can eliminate infections while promoting the healing in diabetic ulcers without using antibiotics.
