2-arm (Tocilizumab + Glucocorticoids (GCs) vs. Placebo + GCs), randomized, placebo-controlled, double blind, monocentric trial in patients with newly onset or relapsing giant cell arteritis (GCA), satisfying ACR criteria AND an elevated sedimentation rate above 40 mm/h and a CRP > 20 mg/L AND a biopsy proven GCA OR a large vessel vasculitis assessed by MR Angiography (MRA).