SBIR Phase I: Development, Optimization and Analysis of Poly (Carboxy Betaine) Bio-conjugates to L-Asparagianse as PEGylation Alternatives

该SBIR第一阶段项目旨在开发一种上级替代目前的一线治疗儿童？急性淋巴细胞白血病（ALL）。主要治疗选择具有由使用与L-天冬酰胺酶缀合的聚（乙二醇）（PEG）引起的许多负面副作用。针对这种药物的抗体会导致身体迅速消除它或导致严重的过敏反应，甚至死亡，特别是在多次注射后（诱导免疫）。PEG已广泛用于食品、化妆品和农业工业。因此，大多数健康人的抗PEG抗体测试呈阳性（预先存在的免疫力），导致PEG修饰的药物在其作用前消除。本文提出的技术利用非必需氨基酸甘氨酸甜菜碱来构建新的聚（羧基甜菜碱）（PCB）聚合物用于缀合，其不被免疫系统识别为外来分子。因此，它将维持功能并减轻与当前治疗相关的与免疫系统相关的负面副作用。此外，使用PCB缀合物的治疗避免了预先存在的对PEG的免疫力，并确保了治疗功效。这项工作的主要目标是表明，该技术是上级和安全性比目前的PEG technology.The技术创新的基础上，这项工作是两性离子，聚（羧基甜菜碱）（PCB）聚合物和它的使用作为一种生物共轭物，以取代广泛使用的聚（乙二醇）（PEG）的治疗儿童？急性淋巴细胞白血病（ALL）。两性离子聚合物的独特性质赋予真正消除免疫原性的生物缀合物显著的特性。目前的一线治疗在患者中存在加速血液清除（ABC），这归因于诱导或预先存在的抗PEG抗体。该I期项目旨在证明PCB是PEG的优选生物缀合聚合物，用于在小鼠中多次给药后延长半衰期和降低免疫原性方面修饰L-天冬酰胺酶。为了实现这些目标，将在聚合物长度和结合密度方面开发优化的PCB L-天冬酰胺酶，并将进行多剂量药代动力学/免疫原性研究，以评估其在动物中的半衰期和免疫保护。将所有结果与PEG对应物的结果进行比较。预期PCB L-天冬酰胺酶具有消除与当前疗法相关的严重副作用的巨大潜力。如果PCB L-天冬酰胺酶被证明是安全有效的，这将导致ALL治疗的更成功的结果。

This SBIR Phase I project aims to develop a superior alternative to the current frontline treatment for children?s Acute Lymphoblastic Leukemia (ALL). The primary treatment option has a host of negative side effects resulting from the use of poly(ethylene glycol) (PEG) conjugated to the L-asparaginase enzyme. Antibodies made against this drug can cause the body to eliminate it rapidly or result in a severe allergic reaction and even death, particularly after multiple injections (induced immunity). PEG has been utilized extensively in the food, cosmetics and agricultural industries. As a result, the majority of healthy people test positive for anti-PEG antibodies (pre-existing immunity), causing the elimination of PEG-modified drugs before their action. The technology proposed here utilizes the non-essential amino acid, glycine betaine, to construct a new poly(carboxybetaine) (PCB) polymer for conjugation that is not recognized as a foreign molecule by the immune system. Therefore, it will maintain function and mitigate the negative side effects associated with the immune system that are attributed to the current therapy. Additionally, therapy with PCB conjugates avoids pre-existing immunity to PEG and ensures treatment efficacy. The primary goal of this work is to show that the technology is superior to and safer than the current PEG technology.The technical innovation at the foundation of this work is the zwitterionic, poly(carboxybetaine) (PCB) polymer and its use as a bio-conjugate to replace the widely used poly(ethylene glycol) (PEG) for the treatment of children?s Acute Lymphoblastic Leukemia (ALL). The unique properties of the zwitterionic polymer impart remarkable characteristics to the bio-conjugate that truly eliminates immunogenicity. The current frontline treatment suffers from Accelerated Blood Clearance (ABC) in patients, which has been attributed to induced or pre-existing anti-PEG antibodies. This Phase I project aims to demonstrate that PCB is a preferable bio-conjugation polymer to PEG for the modification of L-asparaginase with regard to extended half-life and decreased immunogenicity after multiple doses in mice. To achieve the goals, an optimized PCB L-asparaginase will be developed with regard to polymer length and conjugation density and a multi-dose pharmacokinetic/immunogenicity study will be performed to evaluate its half-life and immune protection in animals. All results will be compared with those from its PEG counterpart. It is expected that PCB L-asparaginase has great potential to eradicate the serious side effects associated with the current therapy. If PCB L-asparaginase proves to be safe and effective, this will lead to more successful outcomes for the treatment of ALL.