A remedy and/or a preventive for a chronic disease which contains an EDG-2 antagonist. Because of binding to a subtype EDG-2 of LPA receptor, an EDG-2 antagonist is useful in treating and/or preventing chronic diseases (for example, diseases caused by the progress of chronic asthma, glomerular nephritis, obesity, arteriosclerosis, rheumatoid and atopic diseases) induced and made chronic by tissue cells whose proliferation is accelerated by LPA mediated by EDG-2.