The relentless growth of antibiotic resistance is one of the greatest threats to human health. Antibacterial resistance continues to emerge as bacteria develop new mechanisms to render antibiotics ineffective. Modern trauma-induced or combat-related wound infections are particularly troublesome compared to civilian injuries because the higher velocity projectiles inflicted by weapons such as improvised explosive devices (IEDs) cause more severe injury and accompanying wounds, including burns, and are frequently contaminated by a multitude of pathogenic bacteria and fungi. IEDs account for 75% of all recent war injuries. Innovation in anti-infective agents with broad-spectrum fungal and bacterial activity, including multidrug-resistant organisms (MDROs) and resilient biofilms, is urgently needed so infections can be reduced to a preventable complication of combat-related injuries.

Designed antimicrobial peptides (dAMPs), created by Aero-Dap, LLC, are chemically derived from naturally occurring AMPs, which are ubiquitous in nature and provide the first line of defense against invading pathogens in many pathogens. AMPs have a reduced likelihood of spurring bacterial resistance, exhibit broad antimicrobial activity against Gram-positive and Gram-negative pathogens, are upregulated in response to challenges, and have known anti-inflammatory properties. In this proposed investigation, the in vitro antibacterial and antifungal activity of dAMPs against clinical wound pathogens encountered during combat missions, clinical isolates, and associated biofilms will be determined. Topical formulation of the peptides will be assessed and optimized. The antimicrobial activity of the most promising AMPs will be evaluated in a cutaneous wound infected animal model. If successful, a product candidate will be selected to be advanced to Food and Drug Administration-required preclinical studies with the goal of developing a commercially viable therapy for the topical treatment of wound infections.

The proposed work mirrors the Fiscal Year 2014 Military Infectious Diseases Applied Research Award focus areas as it pertains to the development and preclinical testing (in vitro and in vivo) of novel chemotypes (dAMPs) as therapies or prophylactics for wound infection, and/or biofilm formation, maintenance, or propagation. The focus areas stress the evaluation of innovative treatment approaches in the form of antimicrobial peptide solicitations, which is the focus of the work outlined in this proposal. Additionally, the work entails the use of AMPs for the topical application of a multitude of multidrug resistant organisms (MDROs), including Acinetobacter baumannii, Pseudomonas aeruginosa, extended-spectrum beta-lactamase producing Enterobacteriaceae (including Escherichia coli and Klebsiella pneumoniae), and methicillin-resistant Staphylococcus aureus (MRSA), and invasive fungal pathogens.

The successful implementation of this project will lead to a broad spectrum antibacterial and antifungal therapeutic that disrupts previously impervious biofilm is less likely to develop resistance and promotes wound healing following topical application and thereby can benefit any military and Veteran personnel with trauma-induced or combat-related wound infections.

The technology being developed in this proposal has far-reaching medical implications, particularly as it relates to the treatment of hospital-acquired infections. Nearly 2 million Americans per year develop hospital-acquired (nosocomial) infections, resulting in nearly 100,000 deaths with the majority of these due to drug-resistant bacteria. The ESKAPE pathogens (E. faecium, S. aureus, K. pneumonia, A. baumannii, P. aeruginosa, and Enterobacter species) have the ability to "escape" the effects of antimicrobial treatments due to the development of resistance in addition to biofilm formation. Biofilms are sophisticated colonies of microorganisms encased in a resilient dense extracellular matrix that can develop on or within indwelling medical devices. Antibiotic-resistant infections are estimated to cost the U.S. healthcare system $20 billion a year. Despite the critical need for new antibiotics with novel modes of action, the pace of development of antibacterial agents has drastically declined. The data from the funding of this proposal could lead to the development of a viable product candidate for the treatment of hospital-acquired infections.

Given a successful application, and the enormous unmet medical need associated the development of antipathogenic agents with novel modes of action and minimal susceptibility to microbial resistance, the development, and regulatory path, would be expedited, thereby possibly ensuring a patient-related outcome within 4 to 5 years.