Provided is a novel composition. A composition for cytotoxic T cell depletion, the composition including an anti-LAG-3 antibody or a binding fragment thereof that has the properties described in (i) to (iii): (i) has in vitro ADCC activity； (ii) reduces the number of LAG-3-positive cells in vivo in low-fucose form； and (iii) binds to human activated T cells.
