Optimized Receptor Binding Profile in an Ultra-Stable, Ultra-Rapid-Acting Insulin

描述（由申请人提供）：我们寻求开发一种用于治疗糖尿病的超快速、无锌胰岛素类似物制剂。超快速药代动力学-动态（PK/PD）曲线有望实现泵治疗（连续皮下胰岛素输注）的上级性能，具有增强的安全性和与葡萄糖传感技术的更稳健集成。超快动力学还将促进单次餐时注射后的餐后血糖控制。皮下吸收的障碍是胰岛素自组装。因此，超快速制剂的关键组分将是具有足够内在化学和物理稳定性的工程化胰岛素单体，以使锌介导的自组装变得不必要。这种类似物是20年前开发的（AspB 10-胰岛素），但由于其潜在的致瘤性和相对于天然胰岛素增加的体外促有丝分裂性而未能通过临床前试验。这些特性被认为反映了与IGF-I受体（IGF-1 R）的结合增加和在胰岛素受体（IR）处的停留时间延长。我们已经发现，AspB 10-胰岛素类似物的策略性氟修饰（a）消除了与IGF-1 R的不希望的结合和延长的IR停留时间，同时（B）增强了AspB 10的稳定作用。氟修饰的残基是邻位-F-PheB 24，其适合通过化学合成或通过新的基因工程插入。因此，需要I期支持，以实现与在B28和B29位含有速效B链取代的氟保护AspB 10类似物（来自当前产品Humanoid（R）和Novolog（R））的稳定性、效价、促有丝分裂性和PK/PD相关的里程碑。该提案在蛋白质生物技术中创新性地使用氟（药物化学的支柱），以提高胰岛素替代疗法的安全性和有效性。 公共卫生相关性：糖尿病的全球患病率正在上升。提供更大的便利性，改善血糖控制，减少不良副作用（所有这些都导致更高的合规性和更低的医疗成本），我们已经发明了新的超稳定和超速效胰岛素类似物，（命名为Fluorolog-1和Fluorolog-2），其表现出优化的受体结合特性，减弱AspB 10对与胰岛素受体（IR）和IGF-I受体（IGF-1 R）结合的不希望的影响，原则上降低癌症风险。这些类似物的创新设计利用基于氟的静电工程来“调节”工程化的无锌胰岛素单体的稳定性、促有丝分裂性和效力。本项目将完成Fluorolog-1和Fluorolog-2的可行性测试。

DESCRIPTION (provided by applicant): We seek to develop an ultra-fast, zinc-free insulin analog formulation for the treatment of diabetes mellitus. An ultra-fast pharmacokinetic-dynamic (PK/PD) profile promises to enable superior performance of pump therapy (continuous subcutaneous insulin infusion) with enhanced safety and more robust integration with glucose- sensing technologies. Ultra-fast kinetics would also facilitate post-prandial glycemic control following single mealtime injections. The barrier to subcutaneous absorption is insulin self-assembly. The key component of an ultra-fast formulation would, thus, be an engineered insulin monomer with sufficient intrinsic chemical and physical stability to render zinc-mediated self-assembly unnecessary. Such an analog was developed 20 years ago (AspB10-insulin), but failed preclinical testing due to its potential tumorigenicity and increased in vitro mitogenicity relative to native insulin. These properties are thought to reflect increased binding to the IGF-I receptor (IGF-1R) and prolonged residence time at the insulin receptor (IR). We have discovered that a strategic fluoro-modification of an AspB10-insulin analog (a) eliminates undesirable binding to IGF-1R and prolonged IR residence time and, at the same time, (b) enhances the stabilizing effects of AspB10. The fluoro-modified residue is ortho-F-PheB24, which is amenable to insertion by chemical synthesis or by novel genetic engineering. Phase-I support is, therefore, requested to achieve milestones related to the stability, potency, mitogenicity, and PK/PD of fluoro-protected AspB10 analogs containing rapid-acting B-chain substitutions at positions B28 and B29 (derived from current products Humalog(R) and Novolog(R)). This proposal makes innovative use of fluorine (a mainstay of medicinal chemistry) in protein biotechnology to enhance the safety and efficacy of insulin replacement therapy. PUBLIC HEALTH RELEVANCE: Diabetes is increasing in global prevalence. To provide greater convenience, improved glycemic control, and fewer adverse side-effects (all of which result in greater compliance and lower healthcare costs), we have invented novel ultra-stable and ultra-rapid-acting insulin analogs (designated Fluorolog-1 and Fluorolog-2) that exhibit optimized receptor binding profiles attenuating unwanted effects of AspB10 on binding to the insulin receptor (IR) and the IGF-I receptor (IGF-1R), in principle reducing cancer risk. The innovative design of these analogs exploits fluorine-based electrostatic engineering to "tune" the stability, mitogenicity, and potency of an engineered Zn-free insulin monomer. This project will complete feasibility testing on Fluorolog-1 and Fluorolog-2.