Rituximab limits glucocorticoid use in IgG4-related disease: Real-world evidence from a large European cohort.

Abstract

While glucocorticoids have been considered the standard of care for IgG4-related disease (IgG4-RD), rituximab is increasingly used off-label. We aimed to evaluate the glucocorticoid-sparing ability of rituximab using real-world data. This was an observational multicenter study including adult IgG4-RD patients from three European referral centers treated with glucocorticoids or rituximab (± glucocorticoids). The primary endpoint was no glucocorticoid use at 6 months. Secondary endpoints included treatment response (≥ 2-point decline in responder index (RI)), remission (RI = 0) and flare. Key safety measures included infections requiring hospitalization, and death. We applied logistic regression adjusted for potential confounders. We included 167 patients, 115 (68.9 %) in the rituximab and 52 (31.1 %) in the glucocorticoid group. At baseline, the rituximab group was younger, had longer disease duration, more often relapsing disease and higher RI score than the glucocorticoid group. Despite these indicators of more severe disease, a higher proportion of patients in the rituximab group were free from glucocorticoids by 6 months (OR 3.62, 95 % CI 1.06-12.43, p = 0.040). The median cumulative prednisolone dose at 12 months was 1640.0 mg (IQR 150.0-2578.8) for the rituximab group, and 2950.0 mg (IQR 2302.0-4120.0) for the glucocorticoid group (p < 0.001). The secondary endpoints were similar between groups. While the rituximab-treated patients in this study had more severe IgG4-RD than the glucocorticoid-treated comparators, treatment with rituximab was associated with similar effectiveness endpoints, while significantly reducing glucocorticoid use.