Rituximab therapy achieves comparable remission to cyclophosphamide in ANCA-associated vasculitis with severe KIDNEY involvement

Abstract

Abstract Introduction The RAVE/RITUXIVAS trials established rituximab (RTX) therapy in ANCA-associated vasculitis (AAV). However, RAVE excluded patients with severe renal involvement (creatinine > 354 µmol/L). Whilst RITUXIVAS did not, treatment included RTX with 2 cyclophosphamide (CYC) pulses. This study reports outcomes in AAV patients with severe renal involvement treated with RTX alone compared to CYC, together with high dose steroids. Methods Data were collected retrospectively for all consecutive AAV presentations with severe renal involvement (peak creatinine >354 µmol/L) between 2010–2023 from two renal units. The primary outcome was sustained remission with independent renal function at 12 months. Results Amongst 107 de novo AAV patients, 66 received pulsed CYC with steroids (39 received plasma exchange (PLEX)), and 41 received RTX with steroids (7 received PLEX). At presentation, there was no significant difference in, renal replacement therapy requirement (CYC, 56% vs RTX, 71%; p = 0.129), peak creatinine (511 vs 538 µmol/L; p = 0.399) or eGFR (9 vs 7 mL/min/1.73m2; p = 0.372). 52% of CYC patients, and 49% of RTX patients met the primary outcome (p = 0.783). At 12 months, there was no significant difference in the proportion of patients with independent renal function (CYC, 65% vs RTX, 56%; p = 0.582), eGFR was similar between CYC and RTX patients (28 vs 31 mL/min/1.73m2, p = 0.439), and 94% of CYC cohort were alive compared to 83% of RTX (p = 0.068). Conclusion RTX with steroids is comparable to CYC with steroids to successfully induce remission in AAV with severe renal involvement.