Avacopan beneficial in ANCA-related vasculitis patients on rituximab

Avacopan, when added to background induction therapy with rituximab, is as efficacious as a prednisone taper in terms of inducing remission at week 26 and is associated with a higher rate of sustained remission at week 52 in patients with antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis, according to the phase III ADVOCATE trial.

ADVOCATE randomly assigned 330 patients to receive avacopan (30 mg two times per day) or matching placebo for 52 weeks. Prednisone or a matched placebo was administered on a tapering schedule over 20 weeks (60 mg per day tapered to discontinuation by week 21). Rituximab was given intravenously at 375 mg/m² of body surface area per week for 4 weeks.

The present subgroup analysis comprised 214 patients (64.8 percent) who received rituximab. Their mean age was 59.8 years, and most patients were men (52.8 percent) and White (84.6 percent). The mean baseline estimated glomerular filtration (eGFR) for patients with renal involvement was 50.8 mL/min/1.73m2 in the avacopan group and 46.8 mL/min/1.73m2 in the prednisone taper group.

Remission at week 26 occurred in 83 of 107 patients in the avacopan group (77.6 percent) and in 76 of 107 patients (71.0 percent) in the avacopan group and in 81 of 107 patients in the prednisone taper group. The respective rates of sustained remission at week 52 were 71.0 percent and 56.1 percent.

Results for relapse, recovery of renal function, speed of reduction in albuminuria and glucocorticoid toxicity all favoured the avacopan group.

In terms of safety, 34.6 percent and 39.3 percent of patients in the avacopan and prednisone taper groups, respectively, experienced serious adverse events.

The findings suggest the avacopan is safe and efficacious in patients receiving background induction therapy with rituximab.