Protein Engineering of a Biologic Drug Candidate

项目摘要/摘要 吸烟每年造成近50万人死亡。在美国，直接医疗成本 每年用于治疗吸烟和吸烟引起的疾病的资金超过1700亿美元。只有约20%-25%的吸烟者实现长期- 长期戒烟使用标准护理药物疗法使大多数人仍在吸烟和寻求 另类选择。本项目的重点是进一步评估一种新的尼古丁降解物的蛋白质性质。 酶及其作为戒烟治疗的适宜性。尼古丁的酶降解是一种新的 治疗戒烟的方法。活体实验的临床“原则证明”已经确立 滥用药物的酶降解：两种可卡因降解酶显示出令人鼓舞的结果 阶段1/2结果。 需要对这种酶的生物学特性进行工程设计，以降低潜在的免疫原性并 延长血清半衰期，以确保患者的安全性、足够的稳定性和酶作用时间。至 为此，我们将研究大尺寸无毒聚乙烯的化学偶联--聚乙二醇化的效果 乙二醇基(PEG)连接到酶的表面，为潜在的表位提供空间掩蔽 增加了蛋白质的流体动力学半径，降低了其肾脏清除率。聚乙二醇化的领先候选人 将通过一系列体外酶和血清稳定性分析以及体内模型进行进展 评估聚乙二醇化对免疫原性和药代动力学特性的影响。 这个项目的目标是降低免疫原性并增加这种新型抗体的血清稳定性。 酶通过优化各种聚乙二醇化策略，同时保持其有效的尼古丁降解 活动。实现这些目标将为进行进一步的导联优化提供支持的临床前证据 成瘾动物行为模型的努力和多剂量研究(第二阶段建议)； 将这种新的尼古丁降解酶戒烟方法进展到临床前开发。

Project Summary/Abstract Cigarette smoking is responsible for nearly one-half million deaths/yr. in the U.S. where direct healthcare costs to treat smoking and smoking-attributable illness exceed $170 billion/year. Only ~20-25% smokers achieve long- term abstinence using standard of care pharmacotherapies leaving the majority still smoking and seeking alternatives. The focus of this project is to further assess the protein properties of a novel nicotine-degrading enzyme and its suitability for use as a smoking cessation treatment. Enzymatic degradation of nicotine is a new approach for treating smoking cessation. Clinical “proof-of-principle” has already been established for in vivo enzymatic degradation of drugs of abuse: two cocaine-degrading enzymes have demonstrated encouraging phase 1/2 results. Engineering of the biological properties of this enzyme is needed to reduce potential immunogenicity and to extend serum half-life, in order to ensure patient safety, sufficient stability and duration of enzymatic action. To this end we will investigate the effect of PEGylation, the chemical conjugation of large non-toxic polyethylene glycol (PEG) moieties to the surface of the enzyme, which provide steric masking of potential epitopes and enhanced hydrodynamic radius of the protein, decreasing its rate of renal clearance. PEGylated lead candidates will be progressed through a series of in vitro enzyme and serum stability assays, as well as in vivo models to assess PEGylation’s effects on immunogenic potential and pharmacokinetic properties. The goal of this project is to reduce the immunogenic potential and increase the serum stability of this novel enzyme though optimization of various PEGylation strategies, while maintaining its potent nicotine-degrading activity. Achieving these goals will provide supportive pre-clinical evidence to conduct further lead optimization efforts and multiple-dose studies in animal behavioral models of addiction (Phase II proposal); thereby progressing this novel nicotine degrading enzyme approach for smoking cessation into pre-clinical development.