Lower-dose glucocorticoid therapy achieves comparable outcomes in Japanese patients with lupus nephritis

ObjectiveTo evaluate the effectiveness of a lower initial glucocorticoid (GC) dose (0.4-0.6 mg/kg/day) compared to the conventional dose (0.8-1.2 mg/kg/day) in achieving complete renal response (CRR) at 12 months in Japanese patients with proliferative lupus nephritis (LN).MethodsThis multicentre, retrospective observational study analyzed data from 344 Japanese patients diagnosed with LN (class III or IV ± V) via renal biopsy. Patients were divided into two groups based on their initial dose of GC. 1:1 propensity score matching (PSM) based on key baseline variables, 23 patients were included in each group. The primary endpoint was CRR at 12 months, defined according to the BLISS-LN trial criteria. A non-inferiority margin of -10% was prespecified.ResultsAfter PSM, the CRR rate at 12 months was 87.0% in the low-dose group and 73.9% in the conventional-dose group (risk difference: 13.1%; 95% confidence interval [CI]: -9.4% to 35.6%), confirming statistical non-inferiority. While GC doses differed significantly during the initial 3 months, they became comparable between the groups after 6 months.ConclusionA reduced initial GC dose of 0.4-0.6 mg/kg/day achieved renal outcomes comparable to conventional dosing in Japanese patients with LN. Given the risks of GC toxicity, these findings may support the potential for lower-dose GC strategies in LN treatment.