OBJECTIVE To evaluate the effect of IL-6 blockade using tocilizumab in inducing remission of arterial large vessel vasculitides (LVV). METHODS Five consecutive patients with giant-cell arteritis (GCA) and two with Takayasu's arteritis (TA) were treated by tocilizumab infusions (8 mg/kg). Tocilizumab was given every other week for the first month and once monthly thereafter. Clinical symptoms of disease activity, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) level and glucocorticoid (GC) dosage necessary to maintain remission were prospectively assessed. MR angiography was performed to monitor local inflammation. RESULTS Of the seven patients three were newly diagnosed and four showed GC resistance, i.e. GC could not be lowered to less than 7.5 mg/day. The mean follow-up time was 4.3 months (range 3-7 months). All patients achieved a rapid and complete clinical response and normalisation of the acute phase proteins. Remarkably, prednisone dosage could be reduced within 12 weeks to a mean of 2.5 mg/day (range 0-10 mg/day). No relapse and no drug-related side effects were noted. CONCLUSION Collectively the data suggest that IL-6 blockade using tocilizumab qualifies as a therapeutic option to induce rapid remission in large vessel vasculitides.