As antibody variants and isoforms having reduced FVIII mimetic activity than Emicizumab, the antibody variants having some specific amino acid residues in the variable region cleaved out and missing (Q-CDR-Clipped Variants) and the antibody isoforms having inter-heavy chain disulfide bonds less susceptible to reduction under mild reducing conditions (Protected Disulfide Isoforms) are provided.本發明提供於可變區之特定胺基酸殘基被切斷而缺損之抗體變異體(Q-CDR-斷裂變異體),及於溫和的還原條件下,重鏈間之雙硫鍵不易還原的抗體同功型(受保護的雙硫同功型)之相較於艾美賽珠單抗、類FVIII活性為低之抗體變異體與同功型。