#6809 pulse versus daily oral cyclophosphamide in anca-associated vasculitis with renal involvement: a single center experience

Abstract Background and Aims We aimed to compare the risk of death, relapse and infections requiring hospital admission of ANCA-associated vasculitis (AAV) patients according to the induction of remission scheme used: daily oral (PO) cyclophosphamide or pulse intravenous (IV) cyclophosphamide. Method We identified all newly diagnosed AAV patients treated with PO or IV cyclophosphamide between January 1998 and December 2022 admitted to the CHVNGE Nephrology Department. Data were analyzed with SPSS v28® using parametric and non-parametric tests and Kaplan Meyer survival analysis. Results We identified 74 cases of de novo vasculitis, 50 of them received PO cyclophosphamide and 24 received IV cyclophosphamide. Median age at presentation was 68,50 ± 16,06 years PO and 68,00 ± 10,41 years IV. Median duration of follow-up was 3,8 years ± 2,98 for both groups, 6,21 years PO and 3,88 years IV. One-year survival was 84% in PO and 91,3% in IV patients; 15 (30%) PO and 5 (20,8%) pulse patients had at least one relapse. Neoplasms occurred in 3 (6%) patients in the PO group and 1 (4,2%) patient in the IV group. The number of patients admitted with one or more infections was 22 (44%) in the PO group and 9 (37,5%) in the IV group. Renal survival was 26 (52%) PO and 15 (62,5%) IV. There was no difference in survival (p = 0,176), renal survival (p = 0,113), risk of relapse (p = 0,283) and infection (p = 0,196) between the two groups. Conclusion There was no difference in renal or overall survival, confirming the previous published data. Contrasting with CYCLOPS, our analysis does not confirm an increased risk of relapse in the IV group. One particularly interesting data is that the number of infections in IV route was lower than PO, corroborating the data on lower cumulative doses and therefore lower risk of infection in previous studies. Potential bias of this study is the small sample of patients enrolled in the two groups and the duration of follow up. Despite the reduction in the cumulative dose of cyclophosphamide, we continue to have significant adverse effects, which can also be explained by the dose of corticosteroid previously used, therefore strategies to reduce the toxicity associated with treatment without compromising efficacy are important goals for future research. Treatments need to be optimized and customized according to the severity of the patient's disease and the risk of recurrence.