To provide a formulation for an anti-α4β7 antibody.SOLUTION : There is provided a pharmaceutical composition for treating inflammatory bowel disease in a human patient. The composition comprises a humanized anti-α4β7 antibody comprising : a heavy chain variable region comprising complementarity determining region 1 (CDR1) represented by SEQ ID NO : 8, CDR2 represented by SEQ ID NO : 9, and CDR3 represented by SEQ ID NO : 10; and a light chain variable region comprising CDR1 represented by SEQ ID NO : 11, CDR2 represented by SEQ ID NO : 12, and CDR3 represented by SEQ ID NO : 13. The antibody is subcutaneously administered at a dose of 108 mg to the human patient every two weeks.SELECTED DRAWING : None