In this study, anifrolumab’s (type I interferon receptor antibody) efficacy and safety were examined in patients with active, biopsy-proven, Class III/IV lupus nephritis. Findings revealed that anifrolumab intensified regimen (IR) was linked with numerical improvements over placebo across endpoints, including complete renal response (CRR), although primary endpoint was not met.

• In this phase II double-blinded study, 147 patients were randomized (1:1:1) to receive monthly intravenous anifrolumab basic regimen (BR, 300 mg; n=45), intensified regimen (IR, 900 mg ×3, 300 mg thereafter; n=51) or placebo (n=49), alongside standard therapy (oral glucocorticoids, mycophenolate mofetil).

• Primary endpoint was defined as alteration in baseline 24-hour urine protein–creatinine ratio (UPCR) at week (W) 52 for combined anifrolumab vs placebo groups.

• In the combined anifrolumab and placebo groups, 24-hour UPCR improved by 69% and 70%, respectively, at W52.

• Serum levels were detected to be higher with anifrolumab IR vs anifrolumab BR, which offered suboptimal exposure.

• In the anifrolumab IR group, numerically more patients achieved CRR (45.5% vs 31.1%), CRR with UPCR ≤0.5 mg/mg (40.9% vs 26.7%), CRR with inactive urinary sediment (40.9% vs 13.3%) and sustained glucocorticoid decreases (55.6% vs 33.3%), compared to placebo.

• Combined anifrolumab was associated with higher incidence of herpes zoster vs placebo (16.7% vs 8.2%).

• Across groups, a similar incidence of serious adverse events was observed.