Tocilizumab in the treatment of the adult-onset Still's disease: current clinical evidence

This study aimed to review and analyze the effectiveness and safety of tocilizumab in the treatment of patients with adult-onset Still's disease (AOSD). We report on two patients with AOSD who were successfully treated with tocilizumab. All published information on the use of tocilizumab in this disease was also retrieved through a systematic review of the English-language literature. Including our cases, 35 patients were given tocilizumab for AOSD (8 mg/kg/month in 22 patients). The main clinical manifestations were arthritis in all 35 patients and systemic symptoms such as fever or skin rash in 28 (80 %). Thirty-three (94 %) patients had unsuccessfully tried other immunosuppressive agents such as methotrexate, tumor necrosis factor-α blockers, or anakinra. Most of the patients achieved a response with tocilizumab, such as a prompt articular improvement in 30/35 (86 %) patients and a disappearance of systemic symptoms in 27/28 (96 %). Twenty-eight (80 %) patients tapered their steroid intakes, including seven (20 %) who were able to discontinue them. Four (11 %) patients relapsed, and two were successfully retreated with tocilizumab. Regarding safety, tocilizumab is a well-tolerated treatment, but severe side effects such as macrophage activation syndrome or cytomegalovirus reactivation are possible and require ongoing vigilance. Our findings suggest that tocilizumab should probably be proposed in refractory AOSD, as it allows for remission to be induced and the dose of steroid intakes to be reduced. It is a well-tolerated treatment that can be administered according to the therapeutic sequence of rheumatoid arthritis. Further prospective studies are required to assess the better use of this treatment (dosage and duration) and its place among other conventional treatments.