Granulomatosis with polyangiitis (GPA) is a chronic, relapsing, primary systemic small vessel vasculitis associated with anti-neutrophil cytoplasmic antibodies. The disease is characterised by the involvement of various organs. The relapse rate rises from about 20% at 12 months to about 60% at 5 years. The combination of glucocorticoids and cyclophosphamide remains the standard therapy for patients with generalised GPA; nevertheless, some patients do not respond satisfactorily to this treatment. According to EULAR-EDTA recommendations for the management of ANCA-associated vasculitis, RTX should be considered for remission-induction of new-onset as well as major relapse of organ-threatening or life-threatening GPA. Here we present a 35-year-old patient with relapsing GPA successfully treated with RTX. We also highlight the infectious complications of immunosuppressive treatment.