Belimumab administered in combination with glucocorticoids and azathioprine did not lower the risk for relapse in patients with antineutrophil cytoplasm antibody (ANCA)-associated vasculitis, according to recent results published in Arthritis & Rheumatology.
Researchers conducted a randomized, double-blind, controlled trial of 105 patients with ANCA-associated vasculitis who were assigned to receive either belimumab (n=53) or placebo (n=52). All patients were given oral glucocorticoids (≤10 mg/d), azathioprine (2 mg/kg/d), and induction therapy with cyclophosphamide, rituximab, and glucocorticoids. Study participants received a single dose of belimumab 10 mg/kg intravenously, with subsequent doses were given at days 14 and 28 and every 28 days after, or placebo. The primary end point was time to reach the first protocol-specified event, defined using various factors, including the Birmingham Vasculitis Activity Score.
After statistical analysis, the researchers found that patients treated with belimumab did not lower the risk for protocol-specified events (adjusted hazard ratio [aHR], 1.07; 95% CI, 0.44-2.59; P =.884) or for vasculitis relapse (aHR, 0.88; 95% CI, 0.29-2.65; P =.821) vs placebo. In addition, the investigators reported a higher rate of adverse events in the belimumab group (92.5%) compared with placebo (82.7%).
The primary study limitation was the small sample size, which reduced the statistical power for the primary endpoint.
“Belimumab plus azathioprine and glucocorticoids for the maintenance of remission in [ANCA-associated vasculitis] did not reduce risk of relapse,” the researchers wrote.
“Future studies regarding the maintenance of remission in [ANCA-associated vasculitis] with belimumab as monotherapy may increase the ability of the trial to detect potential treatment benefit,” they concluded.
Jayne D, Blockmans D, Luqmani R, et al. Efficacy and safety of belimumab and azathioprine for maintenance of remission in ANCA-associated vasculitis: a randomized controlled study [published online January 22, 2019]. Arthritis Rheumatol. doi: 10.1002/art.40802