SBIR-STTR Award

The entire Research Plan contains proprietary/privileged information that Imbed Biosciences requests not be released to persons outside the Government, except for purposes of review and evaluation. Title: Ultrathin dissolvable antibiofilm wound contact dressing with silver and gallium Summary The health care costs associated with treatment of chronic and burn wounds exceeds $25 billion annually in the U.S. Biofilms are implicated as a key factor responsible for delayed healing in chronic wounds. Many wounds have complex surfaces and debridement can be challenging, leaving biofilm fragments that remain resistant to antimicrobial therapy and act as a nidus for recrudescence of biofilms. This underscores the unmet need for a cost-effective and non-cytotoxic antibiofilm wound dressing. There is currently no commercially available wound dressing that is clinically indicated for dispersal of biofilms in a wound bed. Imbed Biosciences Inc. has developed and commercialized a unique microfilm wound contact dressing with silver nanoparticles, named MicroLyte Ag, based on its patented polymeric multilayer nanofilm technology, that conforms to the micro-contours of a wound bed, provides an intimate and sustained contact of active agents with the wound bed, and requires 100x lower concentration of silver ions (compared to conventional dressings) to achieve therapeutic efficacy without cytotoxicity. MicroLyte Ag is highly effective in killing planktonic bacteria and has demonstrated efficacy in suppression of biofilm formation. However, the next challenge is to create a wound dressing that will stimulate dispersal of established biofilms in wounds. Our preliminary data shows that Ag+ and Ga3+ biofilm, when delivered through polyelectrolyte multilayer nanofilm, achieved 1000x greater reduction in biofilm CFU than a corresponding topical formulation. This research project will test the hypothesis that sensitization of microbes in biofilms by antibiofilm gallium would enable non-cytotoxic levels of antimicrobial silver to kill biofilm-encased bacteria. There is currently no commercial wound dressing or topical formulation that employs gallium as an antibiofilm agent. Our preliminary experiments have shown that MicroLyte Ag-Ga prototypes can achieve up to 4 Log10 CFU reduction in 48 h old P. aeruginosa biofilms and disperse ? 90% of biofilm mass in vitro, despite releasing 5-10x lower levels of Ag+ than commercial antimicrobial dressings that did not exhibit any significant antibiofilm activity. This proposal seeks to advance development of a next-generation antimicrobial-antibiofilm wound dressing containing silver and gallium. The goal of this Phase 1 feasibility research is to: (AIM 1) Identify silver and gallium loadings in MicroLyte Ag-Ga that exert antibiofilm activity against single and multispecies biofilms of P. aeruginosa and S. aureus without in vitro cytotoxicity and, (AIM 2) Evaluate efficacy of MicroLyte Ag-Ga in dispersal of preformed biofilms in splinted murine wounds. For this project, Imbed has assembled a team of researchers with substantial expertise in biomaterials (Agarwal, Dalsin, Pranami, and Abbott), microbiology (Czuprynski), animal wound models (McAnulty) and clinical wound care (McAnulty and Schurr). Successful completion of Phase 1 research will provide feasibility data for a Phase 2 project to study dispersal of biofilms of multiple bacterial strains in murine/porcine wound models.

Project Terms:
Address; Advanced Development; Animals; Antibiotics; antimicrobial; antimicrobial drug; Antimicrobial Resistance; Bacteria; base; Beds; Biocompatible Materials; Biological Sciences; Biopsy; Caring; Chronic; chronic wound; Clinical; Clinics and Hospitals; Complex; cost effective; cytotoxicity; Data; Debridement; design; Discipline of Nursing; Economics; Evaluation; experimental study; Family suidae; Formulation; Gallium; Goals; Government; Growth; healing; Health Care Costs; Healthcare; Hybrids; Impaired wound healing; In Vitro; in vivo evaluation; Ions; Legal patent; Length of Stay; Metabolism; Microbe; microbial; Microbial Biofilms; Microbiology; Microfilm; Modeling; Mus; Names; nanoparticle; next generation; Organism; Pain; Patients; Persons; Phase; phase 2 study; Polymers; Preparation; prevent; prototype; Pseudomonas aeruginosa; Recrudescences; Recurrence; Research; Research Personnel; Research Project Grants; Resistance; Silver; Small Business Innovation Research Grant; Source; Splint Device; standard of care; Staphylococcus aureus; Sterile coverings; Surface; synergism; Technology; Testing; Therapeutic; Time; Tissues; Transition Elements; Treatment Cost; Treatment Efficacy; Visit; wound; wound closure; Wound Infection;

The entire Research Plan contains proprietary/privileged information that Imbed Biosciences requests not be released to persons outside the Government, except for purposes of review and evaluation.! ! SUMMARY The health care costs associated with treatment of chronic wounds exceeds $25 billion annually in the U.S. Biofilms are implicated as a key factor responsible for delayed healing. Many wounds have complex surfaces and debridement can be challenging, leaving biofilm fragments that remain resistant to antimicrobial therapy and act as a nidus for recrudescence of biofilms. There is no commercially available topical formulation effective in dispersal of biofilms in wounds. Research at Imbed Biosciences, funded by NIH and private equity investments, has resulted in the development of an ultrathin wound contact matrix with a unique form factor. MicroLyte® Matrix is a 20-25 µm-thick dissolvable polymeric multilayer film that allows painless placement in wounds and can be engineered to dissolve over several days. The ultrathin matrix conforms intimately to the underlying contours of a wound bed to provide localized and long-term release of bioactive molecules. Imbed recently obtained FDA clearance for MicroLyte® Ag wound matrix based on that platform, where the matrix was impregnated with silver nanoparticles formed in situ. It has been used successfully to heal chronic wounds in thousands of patients in U.S. It is effective in killing a broad spectrum of bacteria in vitro and in infected wound models in mice. However, it is not effective in killing bacteria encased in biofilms. In our recently published study, we demonstrated synergy of silver and gallium (Ga3+) ions in eliminating biofilms. Based on those scientific findings and successful clinical adoption of MicroLyte® Ag matrix ultrathin form factor in hospitals, objective of this SBIR project is to develop an economic, easy to place, dissolvable wound contact matrix that can deploy synergy of silver and gallium on a wound surface to eliminate biofilms. Results of Phase 1 feasibility study documented that MicroLyte Matrix, when strategically impregnated with non-toxic loadings of silver nanoparticles and gallium in polymeric multilayers, is able to disperse >4 log10 CFUs of bacteria in a mixed species biofilm in vitro. In a delayed wound healing model in mice, such a matrix eliminated >90% of bacteria in a pre-established robust biofilm within 3 days of treatment. These results proved our scientific premise of amplifying synergy in pairing gallium and silver ions against biofilm bacteria by presenting them in a microscale matrix. Phase 1 results provide strong support for pursuing a Phase 2 study to optimize the MicroLyte Matrix design that can obtain faster elimination of biofilms in the wound bed. The goals of Phase 2 research are: (1) Tailor MicroLyte Matrix for higher loadings and extended release of silver and gallium, (2) Screen biocompatibility limits of silver and gallium in the matrix, (3) Screen dose response against mixed species biofilms in vitro, (4) Optimize loadings for dispersal of biofilms in a murine splinted-wound model, and (5) Evaluate effect on healing in a porcine wound model infected with biofilms. For this project, Imbed has assembled a team of researchers with substantial expertise in biomaterials (Agarwal, Pranami, Dalsin, and Abbott), microbiology (Czuprynski), animal wound models (McAnulty) and clinical wound care (McAnulty and Schurr). Successful completion of Phase 2 research will result in a shelf-stable MicroLyte Ag/Ga matrix with safety and efficacy data that can be readily translated into human clinical studies for FDA clearance. !

Public Health Relevance Statement:
NARRATIVE Wound management presents a huge economic and healthcare burden in the U.S. The research described in this SBIR application will lead to the realization of a new form factor for wound management: an ultrathin dissolvable matrix that synergistically combines the benefits of antimicrobial and antibiofilm agents to aid wound-bed preparation. The new wound matrix will adhere intimately to the contours of wound-bed, allow moist wound healing, and kill bacteria in biofilms hiding in crevices of wound tissue surface. It will reduce the frequency of surgical debridement in chronic wounds by eliminating fragments of biofilms harboring in wound-bed, the breaking the cycle of microbial recrudence in chronic wounds. Adoption of this new antibiofilm matrix in work flow of clinical wound management may expedite wound closure, reduce use of antibiotics, reduce nursing time, lower patient pain, reduce length of hospital stays, and reduce overall wound treatment costs.

Project Terms:
Adoption; Animals; Antibiotics; antimicrobial; Antimicrobial Resistance; Architecture; Bacteria; base; Beds; Biocompatible Materials; Biological Sciences; biomaterial compatibility; Caring; Chronic; chronic wound; Clinic; Clinical; Clinical Research; Collagen; Complex; crosslink; Data; Debridement; design; Development; Devices; Discipline of Nursing; Dose; Economics; Engineering; Evaluation; experience; Family suidae; Feasibility Studies; fighting; Film; Formulation; Frequencies; Funding; Gallium; Goals; Government; healing; Health Care Costs; Healthcare; Hospitals; Human; Impaired wound healing; In Situ; In Vitro; Investments; Ions; Length of Stay; microbial; Microbial Biofilms; Microbiology; Microfilm; Modeling; Mus; nanoparticle; Operative Surgical Procedures; Oral cavity; Pain; Painless; Patients; Performance; Persons; Phase; phase 2 study; Platelet Factor 4; Polymers; polymicrobial biofilm; Preparation; Privatization; Publications; Publishing; Recrudescences; Reproducibility; Research; Research Personnel; Resistance; response; restoration; Safety; Silver; Small Business Innovation Research Grant; Source; Splint Device; standard of care; Sterile coverings; Surface; synergism; Thick; Time; Tissue Adhesives; Tissues; Topical Antibiotic; Translating; Transplantation; Treatment Cost; treatment duration; Treatment Efficacy; United States National Institutes of Health; Work; wound; wound closure; Wound Healing