Adult-onset Still's disease (AOSD) is a chronic inflammatory disease of unknown etiology which commonly affects young adults. Treatment of AOSD patients includes nonsteroidal anti-inflammatory drugs, corticosteroids, and DMARDs. Interleukin (IL)-6 blockade is an attractive therapeutic option for AOSD because this cytokine contributes to the pathogenesis of major AOSD symptoms. Tocilizumab (TCZ) is a humanized anti-IL-6 receptor antibody that blocks the effects of IL-6. Preliminary results of TCZ in AOSD have been promising. Here, we reported our experience evaluating both the safety and the efficacy of 12 months therapy with TCZ in 11 patients with AOSD refractory to corticosteroids and MTX therapy, followed for 18 months, including the first 12 months of active treatment and the last 6 months to evaluate the activity of the disease when the treatment was discontinued. The main outcome measures were the European League Against Rheumatism (EULAR) improvement criteria and improvement of systemic symptoms at the 3, 6, 12, and 18-months follow-up periods. Our patients rapidly responded and experienced a sustained clinical remission over time during active treatment. Disease Activity Score 28 decreased from 5.62 (3.75-8.28) [median (range)] at baseline to 1.61(0.49-3.5) at month 12. EULAR remission was achieved in 81.82 % at 12 months. Tender joint and swollen joint counts displayed a progressive reduction during active therapy study period. During treatment, we observed a resolution of fever in our AOSD patient. In conclusion, TCZ might represent a suitable option for the therapy of refractory AOSD patients.