Efficacy and safety of rituximab as maintenance therapy for relapsing granulomatosis with polyangiitis—a case series

A. Knight, H. Hallenberg, E. Baecklund

The objective of this work was to study the efficacy and safety of pre-emptive rituximab (RTX) in a series of patients with severe relapsing granulomatosis with polyangiitis (GPA). GPA is a systemic vasculitis with a high relapse rate despite successful remission induction. Drug toxicity with repeated induction treatments and long-standing immunosuppression poses a problem. Based on the findings in reports on RTX for rheumatoid arthritis, we treated patients with severe relapsing GPA with pre-emptive RTX, 1,000 mg 2 weeks apart every 6 months, aiming at achieving sustainable remission. All patients at one centre with relapsing GPA in spite of traditional maintenance treatment, who had received more than or equal to three cycles of RTX as regularly repeated pre-emptive maintenance therapy every 6 months, were included in this retrospective study. Information on disease manifestations and activity, treatments, lab parameters and adverse events was extracted from the medical files. Of the 12 included patients, all with a positive proteinase 3-anti-neutrophil cytoplasmic antibodies, generalised disease and a median disease duration of 35 months (21-270), 92 % (11/12) achieved sustainable remission during a median follow-up time of 32 months (range 21-111) from first RTX treatment. Concomitant immunosuppressants were reduced. Infections were the most common adverse events, but infections were an issue also before the start of RTX. RTX administered every 6 months seems to be an effective maintenance treatment in a population with severe, relapsing long-standing GPA. Granulomatous as well as vasculitic manifestations responded equally well. Infections are a problem in this patient group but no new safety problems were identified.