Acid-induced aggregation propensity of nivolumab is dependent on the Fc

作者：Liu, Boning; Guo, Huaizu; Xu, Jin; Qin, Ting; Xu, Lu; Zhang, Junjie; Guo, Qingcheng; Zhang, Dapeng; Qian, Weizhu; Li, Bohua; Dai, Jianxin; Hou, Sheng; Guo, Yajun^*; Wang, Hao^*

来源：mAbs, 2016, 8(6): 1107-1117.

DOI：10.1080/19420862.2016.1197443

• Acid-induced aggregates
• atezolizumab
• Fc
• IgG(4) subclass
• nivolumab
• panitumumab
• Protein A chromatography
• purification process
• tocilizumab
• viral inactivation

Nivolumab, an anti-programmed death (PD)1 IgG(4) antibody, has shown notable success as a cancer treatment. Here, we report that nivolumab was susceptible to aggregation during manufacturing, particularly in routine purification steps. Our experimental results showed that exposure to low pH caused aggregation of nivolumab, and the Fc was primarily responsible for an acid-induced unfolding phenomenon. To compare the intrinsic propensity of acid-induced aggregation for other IgGs subclasses, tocilizumab (IgG(1)), panitumumab (IgG(2)) and atezolizumab (aglyco-IgG(1)) were also investigated. The accurate pH threshold of acid-induced aggregation for individual IgG Fc subclasses was identified and ranked as: IgG(1)<aglyco-IgG(1)<IgG(2)<IgG(4). This result was cross-validated by thermostability and conformation analysis. We also assessed the effect of several protein stabilizers on nivolumab, and found mannitol ameliorated the acid-induced aggregation of the molecule. Our results provide valuable insight into downstream manufacturing process development, especially for immune checkpoint modulating molecules with a human IgG(4) backbone.

• 出版日期2016
• 单位中国人民解放军第二军医大学; 聊城大学; 华南理工大学