THU0401 Successful use of canakinumab in adult-onset still’s disease refractory to short acting IL-1 inhibitors

Background Adult onset Still’s Disease (AOSD) is a protean systemic seronegative spondyloarthropathy with, often dramatic, systemic clinical manifestations, including quotidian fever and a cutaneous eruption. Diagnosis requires exclusion of mimicking disorders. A pattern of RNA expression suggestive of an “Interleukin (IL)-1 signature” has been demonstrated in AOSD patients, suggestive of IL-1’s pathogenic role in the disease. IL-1 inhibition has emerged as an important strategy in the treatment of refractory AOSD. Cases resistant to treatment with systemic corticosteroids, methotrexate and IL-1 inhibitors with short half life, such as anakinra [1] (IL-1 receptor antagonist, IL-ra) and rilonacept (IL-1 trap) have been reported. Canakinumab is a fully humanized monoclonal antibody against IL-1 and currently is the longest acting available IL-1 inhibitor with a half-life of 21–28 days. Canakinumab is approved for use in patients with cryopyrin-associated periodic syndrome (CAPS) and is in development for the treatment of gout and FMF, both autoinflammatory diseases. Objectives To evaluate the efficacy and safety of canakinumab, a long acting IL-1 inhibitor, in adult onset Still’s disease (AOSD) patients recalcitrant to disease modifying anti-rheumatic drugs (DMARDs), non-steroid anti-inflammatory drugs (NSAIDs), prednisone as well as shorter acting IL-1 inhibitors such as anakinra and rilonacept. Methods We identified through retrospective chart review in 2 centers, 4 patients were identified with AOSD either clinically (2 patients) or through serial microarray studies (2 patients) which revealed “IL-1 signature”. All were refractory to DMARDs and short acting IL-1 inhibitors and received off-label compassionate canakinumab. The agent was administered subcutaneously, 150 mg every 8 weeks, following the approved adult dose for CAPS. At the time of the study the patients were being followed prospectively for 6 and 12 months respectively and clinical and laboratory parameters were monitored at every visit. Results All 4 patients met ACR 70% response criteria at 6 and 12 months respectively. The mean global assessments pre and post treatment were 53 and 6 respectively. The mean CRP before treatment was 11.47mg/L and after treatment was 2.25mg/L. The mean global assessment post treatment was on an average 80% less than the pretreatment. No relapses have been observed during the follow up period. The inflammatory markers including serum ferritin, ESR, and CRP remained low. The medication was well tolerated with no adverse effects noted. Conclusions This report includes 4 patients from 2 centers, who were refractory AOSD patients, successfully treated with canakinumab and achieved substantial remission. Prompt sustained response of all 4 patients suggests that use of longer acting IL-1 inhibitors may be beneficial for AOSD patients with refractory disease. References Perdan-Pirkmajer K, Praprotnik S, Tomsic M. 2010. A case of refractory adult-onset Still’s disease successfully controlled with tocilizumab and a review of the literature. Clin Rheumatol. Disclosure of Interest None Declared