FimH-Targeting Antibody-Recruiting Molecules as Novel Drugs for Preventing Complicated Urinary Tract Infections

1摘要。尿路感染(UTI)在世界范围内非常常见，并可导致严重的 2并发症，包括肾瘢痕形成和尿毒血症。标准护理治疗依赖抗生素：Empiric 3单纯尿路感染的治疗(UUTI)、复杂尿路感染的广谱治疗(CUTI)和长期预防 复发性尿路感染(RUTI)4例。这种持续不断的抗生素暴露不仅破坏了肠道微生物群，而且推动了 5对尿路致病性大肠埃希菌和肺炎克雷伯菌的耐药性， 6尿路感染的主要致病因素。耐多药尿路病原体的全球传播，如那些 产超广谱β-内酰胺酶(ESBL)和碳青霉烯类耐药肠杆菌引起的7 8(CRE)，已被疾控中心分别指定为“严重”和“紧急”公共卫生威胁。因此， 9抗击多药耐药的新战略是迫切需要的。一种这样的方法是瞄准并 10抑制UPEC和KP的关键毒力因子FimH粘附素的功能。FIMH是一种表面暴露的， 11促进细菌与宿主膀胱上皮结合的甘露糖结合蛋白及其功能 12对于建立和维持一项普遍定期审议制度是必不可少的。使用这种防粘连策略，一种小分子 13甘露糖苷FimH拮抗剂是由Fimbrion和葛兰素史克联合开发的，目前处于1b期 14项治疗UUTI的临床试验。作为这次合作的后续行动，我们开始探索下一步 15代FimH拮抗剂，通过额外招募抗体，针对更难治疗的慢性尿路感染 16来自宿主免疫系统。这些分子被称为FimH拮抗剂抗体招募分子(FimH-ARM) 17种基于甘露糖苷的治疗药物对FimH靶标具有纳摩尔亲和力，我们的早期原型FimH-Arm 18在UUTI小鼠模型中显示出增强的降低急性膀胱感染严重程度的能力。我们 19假设除了拮抗FimH功能外，FimH-ARM还将提供额外的机制 20通过免疫系统的参与和延长的药代动力学(PK)作用(MOAS)，导致 21治疗慢性尿路感染疗效优于传统甘露糖苷。这项提议的主要目标是：(1)产生一个 22个高效的先导系列FimH-ARM，将招募自然产生的人类抗尿路病原体抗体 23个细菌和(2)在cUTI模型中展示了体内疗效。为了实现这些目标，我们将(I)扩大 24 FimH-Arm文库，通过优化的小鼠PK图谱鉴定有效的先导化合物，以及(Ii)测试 25铅FimH臂在小鼠CUTI模型中的体内效应和(Iii)选择我们的先进的FimH臂和 26建立第二阶段后期销售线索优化的活动、MOA和PK基准。成功将 27定义为：鉴定一种先进的先导FimH臂，在体内显示出优于其亲本的疗效 28个小分子FimH拮抗剂，与标准护理抗生素相比并不逊色，并证明了 29例免疫系统MOAS超越FimH拮抗作用。这些研究将有助于临床前的早期发展。 30一种新的、节省抗生素的治疗方法，用于预防由表达FimH的尿路病原体引起的尿路感染。

1 ABSTRACT. Urinary tract infections (UTI) are extremely common world-wide, and can lead to serious 2 complications, including renal scarring and urosepsis. Standard-of-care treatments rely on antibiotics: empiric 3 treatment for uncomplicated UTI (uUTI), broad-spectrum for complicated UTI (cUTI), and long-term prophylaxis 4 for recurrent UTI (rUTI). This constant antibiotic exposure not only disrupts the gut microbiome but drives 5 antimicrobial resistance among uropathogenic Escherichia coli (UPEC) and Klebsiella pneumoniae (Kp), the 6 predominant causative agents of UTI. The global spread of multidrug-resistant uropathogens, such as those 7 caused by extended spectrum b-lactamase (ESBL)-producing and carbapenem-resistant Enterobacteriaceae 8 (CRE), has been designated by the CDC as “serious” and “urgent” public health threats, respectively. Therefore, 9 new strategies to combat multidrug resistance are desperately needed. One such approach is to target and 10 inhibit the function a key virulence factor of UPEC and Kp, the FimH adhesin. FimH is a surface-exposed, 11 mannose-binding protein that facilitates bacterial binding to the host urinary bladder epithelium, and its function 12 is essential for the establishment and persistence of a UTI. Using this anti-adhesive strategy, a small molecule 13 mannoside FimH antagonist was developed by Fimbrion and GlaxoSmithKline and is currently in Phase 1b 14 clinical trials for the treatment of uUTI. As a follow-up to this collaboration, we began exploring the next 15 generation of FimH antagonists that target the more difficult-to-treat cUTI, by additionally recruiting antibodies 16 from the host immune system. Known as FimH antagonist antibody recruiting molecules (FimH-ARMs), these 17 mannoside-based therapeutics have nanomolar affinity for the FimH target and our early protype FimH-ARM has 18 shown enhanced ability to reduce the severity of acute bladder infection in a mouse model of uUTI. We 19 hypothesize that in addition to antagonism of FimH function, FimH-ARMs will provide additional mechanisms of 20 action (MoAs) through engagement of the immune system and extended pharmacokinetics (PK), resulting in 21 superior efficacy over conventional mannosides in cUTI. The main goals of this proposal are: (1) to generate a 22 highly potent lead series of FimH-ARMs that will recruit naturally occurring human antibodies to uropathogenic 23 bacteria and (2) demonstrate in vivo efficacy in a model of cUTI. To accomplish these goals, we will (i) expand 24 the FimH-ARM library to identify potent lead compounds with optimized mouse PK profiles, and (ii) test the in 25 vivo efficacy of lead FimH-ARMs in a mouse cUTI model and (iii) Select our advanced lead FimH-ARM and 26 establish the spectrum of activity, MoA, and PK benchmarks for late lead optimization in Phase II. Success will 27 be defined as: identification of an advanced lead FimH-ARM, that shows in vivo efficacy superior to its parent 28 small molecule FimH antagonist and non-inferiority to a standard-of-care antibiotic and demonstrates additional 29 immune system MoAs beyond FimH antagonism. These studies will facilitate the early preclinical development 30 of a novel, antibiotic-sparing therapeutic, for preventing cUTI caused by FimH-expressing uropathogens.