【摘要】 目的 探究一种治疗用抗体偶联药物NCB001电荷异构体结构及其对生物学活性的影响。方法 采用阳离子交换色谱对NCB001电荷异构体组分进行分离和收集，通过液质联用(LC-MS/MS)技术进行结构表征，并进一步考察其生物学活性。结果 分离获得的3种电荷异构体纯度较高(接近90%)、相对分子质量正确；3种电荷异构体发生翻译后修饰的位点相同，但与主峰相比，酸性峰中天冬酰胺的脱酰胺化修饰比例显著增高，碱性峰中重链C端甘氨酸缺失后脯氨酸的酰胺化修饰的比例明显升高，并且偶联毒素小分子药物比例明显降低；其他翻译后修饰比例无显著差异。同时，3种电荷异构体之间结合活性和细胞活性无显著差异。结论 电荷异质性不会影响NCB001的生物学活性，3种电荷异构体均应视为合格的药物有效成分。更多还原

【Abstract】 OBJECTIVE To investigate the structures of charge variants of a therapeutic antibody-drug conjugate(NCB001) and their potential effects on biological potencies. METHODS Charge variant fractions of NCB001 were isolated and collected by cation exchange chromatography, and the structures were characterized by LC-MS/MS, while biological potencies were further investigated. RESULTS All of the three collected charge variants were of high purity(about 90%) and correct molecular mass. Same post-translational modification sites were observed for all the three charge variant fractions. As compared with the main peak, significantly higher ratio of asparagine deamidation was observed for acid peak, while significantly higher ratio of proline amidation following the loss of C-terminal glycine and lower ratio of payload conjugation were reported for basic peak. There was no significant difference in other modification ratio among the three charge variants. Meanwhile, no significant differences were observed on both binding potency and cell-based potency among the three charge variant fractions. CONCLUSION Charge heterogeneity does not affect the biological potency of NCB001, and all the three charge variant fractions shall be regarded as qualified drug active ingredients.更多还原