A novel therapeutic strategy for the anti-PD-1 antibody therapy is provided.A pharmaceutical composition which comprises at least one substance selected from the group consisting of the following (i) to (iii) and is administered before, after or simultaneously with the administration of a PD-1 signal inhibitor:(i) ROS generators and substances that regulate downstream signaling pathways thereof,(ii) substances exhibiting an uncoupling effect and substances that regulate downstream signaling pathways thereof, and(iii) amino acids.
