Development of novel anti-biofilm compounds for treating chronic wounds

描述（由申请人提供）：对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，与治疗这些伤口相关的直接成本估计为每年100 - 250亿美元。已经定殖在慢性伤口上的病原菌的根除由于这些细菌形成生物膜的倾向而变得复杂。生物膜由被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免疫应答。处于生物膜状态的细菌对抗生素的耐药性大约高一千倍，并且目前没有可靠的治疗策略可用于分散预先形成的生物膜。 该SBIR项目的范围是评估一类新的分子，称为2-氨基咪唑（2-AI），用于治疗慢性伤口中基于生物膜的感染。2-AI分子是已经显示分散革兰氏阳性和革兰氏阴性细菌的生物膜的第一类非杀微生物小分子。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）的先进体外模型评估了它们的活性。通过这项工作，我们确定了一种名为H10的先导分子，它能有效地分散S.金黄色葡萄球菌和铜绿假单胞菌形成。此外，当来自S.用H10处理金黄色葡萄球菌生物膜。这些结果为2-AI化合物治疗慢性伤口中基于生物膜的感染的潜力提供了强有力的体外证据，并激励了我们的II期项目。 在第二阶段，我们将：1）评估 H10在两种标准体内伤口模型（兔耳和猪）中的有效性和2）进行安全性评价，以便为后续IND启用毒性研究提供信息。将由西北大学的Robert Galiano博士（兔模型）和迈阿密大学的Stephen Davis博士（猪模型）使用兔耳伤口模型和猪伤口模型评价H10作为局部治疗剂，CBE的Garth James博士提供生物膜成像支持。由于H10是非杀微生物的，因此它将与抗生素共同给药，以提供除杀死细菌之外的生物膜的协同去除。精通药物安全性的合同研究组织将进行遗传毒性、皮肤刺激、细胞色素P450抑制和急性毒性评价。该II期项目成功的衡量标准是确定一种H10-抗菌剂组合，该组合可增强体内伤口愈合并具有良好的毒性特征。在这项工作中确定的联合治疗将是 在GLP条件下进行III期IND启动毒性研究。

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.