Inebilizumab Monotherapy in Relapsing IgG4-Related Tubulointerstitial Nephritis

IgG4-related disease (IgG4-RD) is a rare but clinically significant systemic fibroinflammatory disorder affecting multiple organs, characterized by IgG4 plasma cell infiltration and tissue fibrosis, with an estimated prevalence of 5.3 per 100,000 persons in the United States.1,2 Kidney involvement is reported in approximately 7-24% of IgG4-RD cases and represents considerable clinical heterogeneity.3 While glucocorticoids have historically been used as the first-line therapy for IgG4RD, relapse after tapering is very common, creating a significant need for durable, steroid-sparing treatment in order to avoid long term complication of prolonged steroid therapy.