FRI0377 Early response to treatment is a surrogate marker of flare recurrence in acute gouty arthritis

Background Canakinumab, a fully human anti-IL-1β monoclonal antibody, selectively targets IL-1β and may be an alternative treatment to NSAIDs or colchicine in patients (pts) presenting with acute gouty arthritis (GA), in whom standard care is inappropriate or ineffective. The ideal qualities of such a treatment should include fast and potent pain relief and reduction of the risk of a new flare. When treating pts with biologic therapy, it is important to develop criteria for response-guided retreatment decisions to reduce risk of futile treatment and potential exposure to an unnecessary safety risk. Objectives To explore the rapidity of response to treatment, defined as ≥50% pain reduction within 7 days, as a potential surrogate marker of time to new flare. Methods A good concordance between prevention of flare and 50% pain reduction on a 0-100 mm visual analogue scale (VAS) was detected in a retrospective pooled analysis of two 12-week studies (β-RELIEVED, N=230; β-RELIEVED-II, N=226) in pts treated with a single dose of canakinumab 150mg sc or triamcinolone acetonide (TA) 40 mg im. The 12-week extension studies allowed evaluation of early pain response as a predictor of delay to new flare. The predictive value of the response was studied using a Cox model with response as a time-dependent covariate and the number of flares in the previous year as baseline predictor. Results 50% pain reduction within 7 days of treatment was confirmed to be a highly significant predictor of time to new flare (p