日本質量分析学会 第71回質量分析総合討論会

演題概要

シンポジウムセッション

第1日 5月15日(月) 13:53~14:15 A会場(特別会議場)

HDX-MSを用いた抗体医薬品の相補性決定領域の切断による構造変化と機能的変化の相関

(1協和キリン2群馬大院理)
o渥美由梨子1,2櫻井奈津子1山田亜由美1小島ゆか1八木有紀1西村晃一郎1山﨑勝由1若松馨2

The presence of monoclonal antibody (mAb) fragments in pharmaceutical mAb products is a critical quality attribute and should be controlled for safety. Several mAb fragments derived from clip formation in the complementarity determining regions (CDRs), as well as from cleavage in the hinge region, have been reported. However, the properties of CDR-clipped variants are not fully understood because of difficulties in separating them from intact mAbs under non-denaturing condition due to similarities in size. We have established a method for separating CDR-clipped variants under non-denaturing condition using an appropriate size exclusion chromatography column.1) We provide a comprehensive characterization of a CDR-clipped variant from bevacizumab.2) The variant exhibited a lower affinity for antigen, neonatal Fc receptor (FcRn), and Fcγ receptor (FcγR). The effects of clip formation in CDR H3 on the higher order structure were analyzed by hydrogen/deuterium exchange mass spectrometry, and the observed changes in the structures of the VH, CH2, and VL domains were in agreement with the lowered affinity for antigen, FcRn, and FcγR. These findings suggest that clip formation in the CDR may affect the efficacy, safety, and pharmacokinetics of pharmaceutical mAbs.