A multicenter retrospective case-control study on Suspension of TNF-inhibitors and Outcomes in Psoriatic patients (STOP study)

Background There is limited information on patients undergoing withdrawal after long-term treatment with anti-TNF alpha drugs and their clinical evolution during the post-interruption period in real-life settings. The purpose of the present retrospective case-control study was to provide a clearer insight into the clinical management of psoriatic patients with adequate response to long-term adalimumab, etanercept and infliximab treatment once these biologic agents are interrupted. Methods A total of 270 patients undergoing anti-TNF alpha agents discontinuation and 253 controls treated with a continuous regimen were enrolled. The primary endpoint was the change in disease activity in each study group over six months (or until treatment of psoriatic recurrence) as measured by the PASI score every month. Then, we evaluated the rate of and time to relapse, the rate of clinical worsening (PASI≥5) and the clinical variables influencing the loss of response. Results Our study showed that about 50% of patients achieving a long-term and optimal response to the aforementioned anti-TNF alpha agents did not experience any relapse over a 6-month follow-up period after withdrawal. We also observed that subjects displaying a complete remission (PASI=0) at anti-TNF alpha therapy withdrawal experienced less frequently disease worsening and/or relapse compared to subjects having a PASI>0. Conclusions Our findings confirmed that all three anti-TNF alpha agents tend to retain their effectiveness upon re-administration in case of recurrence, even if they have been previously used for long time.