Development of novel anti-biofilm compounds for treating chronic wounds

描述（由申请人提供）：传统治疗干预无效的慢性伤口每年折磨数百万人，仅在美国，每年与治疗这些伤口相关的直接费用估计为100 - 250亿美元。由于这些细菌形成生物膜的倾向，消灭在慢性伤口上定植的致病菌是复杂的。生物膜由细胞外基质包围的细菌群落组成，细胞外基质有效地抵抗抗生素的作用和宿主的免疫反应。处于生物膜状态的细菌对抗生素的耐药性大约高出1000倍，目前还没有可靠的治疗策略来分散预先形成的生物膜。这个SBIR项目的范围是评估一类新的分子，称为2-氨基咪唑（2-AIs），用于治疗慢性伤口中基于生物膜的感染。2-AI分子是一类非杀微生物小分子，已被证明可以分散革兰氏阳性和革兰氏阴性细菌的生物膜。鉴于2-AI分子的非杀微生物性质，它们不会产生可能导致耐药性发展的选择性环境。在第一阶段合成了超过100个2-AI分子，并使用Agile Sciences的高通量筛选和蒙大拿州立大学生物膜工程中心（CBE）的先进体外模型对其活性进行了评估。通过这一努力，我们发现了一种名为H10的先导分子，它有效地分散了金黄色葡萄球菌和铜绿假单胞菌在滴流反应器中形成的坚固的生物膜。此外，当金黄色葡萄球菌生物膜的条件培养基用H10处理时，在人角质细胞划痕闭合模型中实现了伤口的完全闭合。这些结果为2-AI化合物治疗慢性伤口生物膜感染的潜力提供了强有力的体外证据，并激励了我们的二期项目。在第二阶段，我们将：1)评估

DESCRIPTION (provided by applicant): Chronic wounds that fail to respond to traditional therapeutic interventions afflict millions of people each year, and direct costs associated with treating these wounds are estimated at $10-25 billion annually in the U.S. alone. Eradication of pathogenic bacteria that have colonized chronic wounds is complicated by the propensity of these bacteria to form biofilms. A biofilm consists of a community of bacteria encompassed by an extracellular matrix which efficiently resists the action of antibiotics and the host immune response. Bacteria in the biofilm state are approximately one-thousand times more resistant to antibiotics, and there are currently no reliable therapeutic strategies available for dispersing pr-formed biofilms. The scope of this SBIR project is to evaluate a new class of molecules, called the 2-aminoimidazoles (2-AIs), for treating biofilm-based infections in chronic wounds. The 2-AI molecules are the first class of non- microbicidal small molecules that have been shown to disperse biofilms of both Gram-positive and Gram- negative bacteria. Given the non-microbicidal nature of the 2-AI molecules, they do not create a selective environment that could lead to the development of resistance. Over one-hundred 2-AI molecules were synthesized in Phase I and evaluated for their activity using high-throughput screening at Agile Sciences and advanced in vitro models at the Center for Biofilm Engineering (CBE) at Montana State University. Through this effort, we identified a lead molecule, named H10, which effectively disperses robust biofilms of S. aureus and P. aeruginosa formed with a drip flow reactor. Furthermore, full closure of a wound in a human keratinocyte cell scratch closure model was achieved when conditioned media from S. aureus biofilms was treated with H10. These results provide strong in vitro evidence of the potential of the 2-AI compounds to treat biofilm-based infections in chronic wounds, and motivate our Phase II project. In Phase II, we will: 1) evaluate the effectiveness of H10 in two standard in vivo wound models (rabbit ear and porcine) and 2) conduct safety evaluations in order to inform subsequent IND-enabling toxicity studies. Evaluations of H10 as a topical therapeutic using the rabbit ear wound model and the pig wound model will be performed Dr. Robert Galiano of Northwestern (rabbit model) and Dr. Stephen Davis of the University of Miami (pig model) with Dr. Garth James of the CBE providing biofilm imaging support. Since H10 is non-microbicidal, it will be co-dosed with an antibiotic to provide synergistic removal of the biofilm in addition to killing of the bacteria. Contract Research Organizations that are well-versed in drug safety will perform genotoxicity, skin irritation, cytochrome P450 inhibition, and acute toxicity evaluations. The metric of success for this Phase II project is to identify an H10-antimicrobial combination that enhances wound healing in vivo and possesses a favorable toxicity profile. The combination therapy identified in this work will be advanced to IND-enabling toxicity studies to be conducted under GLP conditions in Phase III.