Provided is a prophylactic, symptom progress-suppressive, and/or therapeutic agent for an autoimmune disease. The agent lowers the risk of infections and reduces the burden of administration to patients. The prophylactic, symptom progress-suppressive, and/or therapeutic agent includes a PD-1 agonist as an active ingredient and is administered (a) 1 to 10 times within one month from the first administration, (b) in a total PD-1 agonist dose of 20 to 1250 μg/kg, and (c) without requiring administration for at least 3 months after the last administration.