The effect of discontinuation of maintenance therapy in Chinese patients with MPO-ANCA associated vasculitis who were in long-term stable remission.

There is a consensus that maintenance therapy should be used to prevent relapse of myeloperoxidase-anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (MPO-AAV), but there is a debate about the optimal duration of maintenance therapy. Therefore, the purpose of this study was to determine whether discontinuation of maintenance therapy in MPO-AAV patients who were in long-term stable remission affects relapse, renal survival and patient survival. Seventy-nine patients with MPO-AAV diagnosed at Xiangya hospital from June 2010 to June 2019 who were in stable remission for at least 18 months following maintenance therapy were included. Patient records were retrospectively reviewed, and based on whether patients discontinued maintenance therapy 18 months after commencing maintenance therapy, patients were assigned into either the withdrawal group (n = 26) or maintenance group (n = 53). The endpoint was the percentage of relapse, relapse-free survival, renal survival and patient survival during follow-up. Ten relapses (38.5%) occurred in the withdrawal group (n = 26) and 8 relapses (15.1%) occurred in the maintenance group (n = 53) (p = 0.020). Compared to the withdrawal group, the maintenance group had similar relapse-free survival (log-rank test p = 0.099). But maintenance group had a better renal survival (p = 0.035), with no difference in patient survival or adverse events. This study suggests that discontinuing maintenance therapy at 18 months following induction of sustained remission leads to a significant increase in the percentage of relapse, and decreases renal survival in patients with MPO-AAV, but does not decrease relapse-free survival or patient survival.