Nanocarrier formulated enzyme for the treatment of S. aureus infection

性状（由申请方提供）：溶血素，一种金属内肽酶，对沙门氏菌具有溶菌作用。金黄色葡萄球菌，是一种潜在的全身治疗耐甲氧西林的S。金黄色葡萄球菌（MRSA）介导的感染，包括心内膜炎、骨髓炎、导管相关感染和MRSA介导的社区获得性疖和肺炎。然而，尽管有积极的临床试验数据，但这种酶在体内的半衰期短，阻碍了其作为全身治疗的发展。我们的公司PharmaIN开发了一种纳米载体，保护接枝共聚物（PGC），可以可逆地结合肽和/或蛋白质（美国专利#7，138，105），具有可测量的解离常数（Kd）。重要的是，由于其大小，PGC纳米载体集中在血管通透性增加的部位，因此可能在感染部位集中溶血素。我们的目标是开发一种溶血素制剂，以提供针对MRSA的挽救生命的治疗，并抑制耐药性的出现。我们的初步数据表明，PGC可以可逆地与溶血，增加血液半衰期14倍，并增加其对MRSA的体内疗效100倍。我们建议制备无内毒素的溶血素，并建立一个“主细胞系库”（E。表达lyso的大肠杆菌），将用于：1）本项目以满足我们的lyso需求，以及2）作为计划的SBIR IND申请和临床试验后的参考细胞。我们还将通过合成初步数据中显示的有效PGC的变体（至少10种）来优化PGC的结构，旨在进一步将半衰期延长至至少30倍。在我们将大量资源投入IND之前，这一点很重要。为此，我们将通过对至少10种新载体变体进行结合研究，继续开发PGC-溶血剂制剂。我们将对至少6种选定的溶血剂制剂进行PK和生物分布研究。我们将确定并与市售抗生素比较我们的溶血制剂在体内对抗MRSA的有效性。PharmaIN Corp.机密 公共卫生相关性：我们将开发一种溶葡萄球菌酶（lyso）制剂，以提供针对MRSA的挽救生命的治疗并抑制耐药性的出现。为此，我们将优化PGC的结构，使溶血血液停留时间延长30倍，体内抗MRSA的有效性提高100倍以上。我们还建议制备无内毒素的溶血剂，并建立一个“主细胞系库”（E。表达lyso的大肠杆菌），将用于：1）本项目以满足我们的lyso需求，以及2）作为计划的SBIR IND申请和临床试验后的参考细胞。PharmaIN Corp.机密

DESCRIPTION (provided by applicant): Lyso, a metalloendopeptidase that is bacteriolytic for S. aureus, is a potential systemic therapy for treating methicillin-resistant S. aureus (MRSA) mediated infections including endocarditis, osteomyelitis, catheter related infections, and MRSA-mediated community acquired furunculosis and pneumonia. However, the short half-life of this enzyme in vivo has precluded its development thus far as a systemic therapy, despite positive clinical trial data. Our company, PharmaIN, has developed a nanocarrier, Protected Graft Copolymers (PGC), that can reversibly bind peptides and/or proteins (US patent #7,138,105) with measurable dissociation constant (Kd). Importantly, because of its size, PGC nanocarrier concentrates at sites of increased vascular permeability and thus can potentially concentrate lyso at the site of infection. Our goal is to develop a formulation of lyso to provide life-saving treatment against MRSA and to suppress the emergence of resistance. Our preliminary data demonstrates that PGC can reversibly associate with lyso, increase blood half-life 14-fold, and increase its in vivo efficacy against MRSA by 100-fold. We propose to prepare endotoxin- free lyso and create a "master cell-line bank" (E. coli expressing lyso) that will be used for: 1) this project to supply our lyso needs, and 2) as reference cells for the planned post-SBIR IND filing and clinical trial. We will also optimize the structure of PGC by synthesizing variations (at least 10) of the effective PGC shown in the preliminary data with the intention to further extend the half-life to at least 30 fold. This is important before we put a lot of resource towards IND. To this end, we will continue the development of PGC-lyso formulation by doing binding studies of at least 10 new carrier variations. We will do PKs and biodistribution studies on at least 6 selected lyso formulations. We will determine and compare with commercially available antibiotics the effectiveness of our lyso formulation in vivo against MRSA. PharmaIN Corp. Confidential PUBLIC HEALTH RELEVANCE: We will develop a formulation of lysostaphin (lyso) to provide a life-saving treatment against MRSA and to suppress the emergence of resistance. To this end, we will optimize the structure of PGC to extend lyso blood residence time by 30 fold and effectiveness in vivo against MRSA by more than 100-fold. We also propose to prepare endotoxin-free lyso and create a "master cell-line bank" (E. coli expressing lyso) that will be used for: 1) this project to supply our lyso needs, and 2) as reference cells for the planned post-SBIR IND filing and clinical trial. PharmaIN Corp. Confidential