Disclosed is the use of a compound represented by either of the following Formulae 1 and 2 in the preparation of an agent for maintaining induced remission, said agent being used after the remission has been induced for an immune disease by the administration of a biological agent or a nucleic acid synthesis-5 inhibitory agent, to a patient suffering from said immune disease, said immune disease being selected from the group consisting of inflammatory bowel disease, systemic lupus erythematosus, Crohn disease, nephrotic syndromes, glomerular sclerosis, glomerulonephritis, multiple sclerosis, serious myasthenia, rheumatoid arthritis, psoriasis, allergic contact dermatitis, and atopic dermatitis.
