Rituximab for remission induction in elderly patients with ANCA-associated vasculitis

Abstract

Objectives: Advancing age is a risk factor for treatment-related side effects and mortality in AAV patients treated with cyclophosphamide (CYC) and glucocorticoids (GC) for remission induction. The efficacy and safety of rituximab (RTX) in elderly AAV patients has not been well described.

Methods: We performed a single center retrospective review of 31 consecutive AAV patients aged 60 or more at the time of RTX use for remission induction. All patients received RTX with GC for remission induction. Four patients received concomitant CYC for a mean duration of 52 days. We evaluated clinical and laboratory variables at diagnosis, rates of complete remission defined as Birmingham Vasculitis Activity Score/Wegener's Granulomatosis (BVAS/WG) = 0 and patient survival, renal survival, infections requiring hospitalization, and vasculitis relapse 24 months following RTX use.

Results: Of the 31 patients, 77% were Caucasian, 68% female, mean age was 71 ± 6 years, 58% were MPO ANCA positive, and 42% had relapsing disease. The mean BVAS/WG score entry was 4.4 ± 1.5, 71% had glomerulonephritis (GN) and 10% had alveolar hemorrhage. The mean baseline e-GFR was 40 ± 28ml/min/1.73m(2). Thirty patients achieved remission with a mean time to remission of 57 ± 27 days. The single patient with refractory vasculitis responded to CYC. The mean prednisone dose at 6 months was 5.6 ± 4mg. Remission maintenance therapy was started within 12 months of RTX induction in 6 patients (4 with RTX, 1 with azathioprine, and 1 with mycophenolate mofetil). One patient suffered a limited relapse 10 months post RTX use. Among the 22 patients with GN at baseline, 1 developed ESRD. One-year patient survival among 25 patients with at least 1 year of follow-up was 100%. There were no episodes of infusion reaction or leukopenia. There were 3 episodes of bacterial pneumonia, 1 episode of candida pneumonia, and 1 episode of disseminated cutaneous zoster.

Conclusions: This study demonstrates that rituximab is effective for remission induction in elderly patients with AAV. Furthermore, we observed a high incidence of infectious complications. Our experience was limited by its retrospective design, and further studies are needed to evaluate the efficacy and safety of RTX in elderly AAV patients.

Keywords: AAV (ANCA-associated vasculitis); CYC (cyclophosphamide); Elderly; Eosinophilic granulomatosis with polyangiitis (Churg–Strauss syndrome); Granulomatosis with polyangiitis (Wegener’s); Microscopic polyangiitis (MPA); RTX (rituximab); Renal-limited vasculitis; mAb (monoclonal antibody).