[New strategies for the treatment of IgG4-related disease].

IgG4-related disease is a chronic and fibroinflammatory disorder, which is characterized with elevated levels of serum IgG4, and prominent infiltration of IgG4-bearing plasma cells in the involved organs. It often affects with lacrimal glands, salivary glands, pancreas, kidneys, lungs, and retroperitoneal cavity. Now, the first line of the induction therapy for IgG4-related disease is glucocorticoid, but almost patients need the maintenance treatment and experience the relapse. It is recently reported that biologic agents, including rituximab and abatacept, are effective for the relapse of IgG4-related disease. It is clear that the tapering effect of glucocorticoid is better than conventional oral immunosuppressants. We can use it in safely if we choose the appropriate cases. The investigator-initiated trial of rituximab for IgG4-related disease is scheduled in Japan. This article reviews the new strategies for the treatment of IgG4-related disease with our data of SMART registry, and discuss the problems of each biologic agents for IgG4-related disease.