Objective. Anakinra is effective in adult-onset Still's disease (AOSD) in the short term, but little is known regarding its efficacy over the long term. Our objective was to assess the long-term efficacy and safety of anakinra in AOSD. Methods. A nationwide survey was conducted between 2009 and 2010 to identify AOSD patients treated with anakinra. Collected data consisted of disease characteristics at diagnosis and at medication onset; anakinra efficacy, safety, and dose adaptation; and reasons for discontinuation, if applicable. Results. The study included 28 AOSD patients, with a mean age of 40.3 years and a mean disease duration at the start of anakinra of 9.3 years. All patients had previously failed to respond to steroids and disease-modifying antirheumatic drugs. All patients responded to anakinra, with a rapid and sustained decrease in steroid doses. At the last followup (mean 23 months), 16 patients were still being treated with anakinra: 4 had a partial response and 12 were in complete remission. Twelve patients had discontinued anakinra: 2 due to an insufficient response, 4 due to an AOSD flare after a period of complete remission, 2 due to side effects, and 1 due to a desire for pregnancy. In 3 patients, the drug discontinuation was possible because they achieved complete remission. Six additional patients experienced anakinra dose tapering, with sustained remission in 2 and relapse in the others. Anakinra was well tolerated and adverse events were rated as mild. Conclusion. Anakinra was consistently efficacious in AOSD and displayed good therapeutic maintenance. Anakinra dose tapering or discontinuation was associated with relapse in half of the patients.