Bioconjug Chem. 2019 Nov 20;30(11):2782-2789. doi: 10.1021/acs.bioconjchem.9b00475. Epub 2019 Oct 11.
Treatment of ocular diseases associated with neovascularization currently requires frequent intravitreal injections of antivascular endothelial growth factor (anti-VEGF) therapies. Reducing the required frequency of anti-VEGF injections and associated clinical visits may improve patient adherence to the prescribed treatment regimen and improve outcomes. Herein, we explore conjugation of rabbit and fragment antibodies (Fab) to the biopolymer hyaluronic acid (HA) as a half-life modifying strategy, and assess the impact on Fab biophysical properties and vitreal pharmacokinetics. HA-Fab conjugates of three distinct molecular weights and hydrodynamic radii () were assessed for pharmacokinetic performance relative to unconjugated Fab after intravitreal injection in rabbits. Covalent conjugation to HA did not significantly alter the thermal stability or secondary or tertiary structure, or diminish the potency of the Fab, thereby preserving its pharmacological properties. Conjugation to HA did significantly slow the clearance of Fab from the rabbit vitreous in an -dependent manner. Compared to free Fab (observed vitreal half-life of 2.8 days), HA-Fab conjugates cleared with observed half-lives of 7.6, 10.2, and 18.3 days for 40 kDa, 200 kDa, and 600 kDa HA conjugates, respectively. This work elucidates a possible strategy for long-acting delivery of proteins intended for the treatment of chronic posterior ocular diseases.
目前，治疗与新生血管有关的眼部疾病需要频繁进行玻璃体内注射抗血管内皮生长因子（anti-VEGF）治疗。减少抗 VEGF 注射的频率和相关的临床就诊次数可能会提高患者对规定治疗方案的依从性，并改善治疗效果。在此，我们探讨了将兔源抗体和片段抗体（Fab）与生物聚合物透明质酸（HA）偶联作为一种半衰期修饰策略，并评估了其对 Fab 生物物理性质和玻璃体内药代动力学的影响。评估了三种不同分子量和流体力学半径（）的 HA-Fab 缀合物相对于玻璃体内注射后未缀合 Fab 的药代动力学性能在兔体内。HA 与 Fab 的共价偶联并未显著改变 Fab 的热稳定性或二级或三级结构，也未降低 Fab 的效力，从而保留了其药理学特性。HA 与 Fab 的偶联确实以依赖的方式显著减缓了 Fab 从兔玻璃体内的清除。与游离 Fab（观察到的玻璃体半衰期为 2.8 天）相比，40 kDa、200 kDa 和 600 kDa 的 HA 缀合物的观察半衰期分别为 7.6、10.2 和 18.3 天。这项工作阐明了一种用于治疗慢性后眼部疾病的长效蛋白递送的可能策略。
