Inclusion Criteria:  Age > 60 years Diagnosis of GCA (according to ACR criteria or positive temporal artery biopsy) (de novo and/or relapse) And neurovascular involvement: Either Ischemic stroke (including TIA) in the vertebro-basilar or carotid territory (symptomatic arterial involvement) Either PET uptake of vertebral and/or carotid arteries (extra or intra cranial) and/or angioCT or angioMRI showing arterial involvement consistent with vasculitis (asymptomatic arterial involvement) Inclusion should be done within 4 weeks after the stroke concerning the "symptomatic" patients within 4 weeks after the diagnosis of GCA (or relapse) concerning the patients with asymptomatic neurovascular involvement. Within 14 days after starting the corticosteroids Signed Informed Consent Form Affiliation to social security  Exclusion Criteria:  Exclusion Criteria :  Other proven cause of stroke: atrial fibrillation, significant atheromatous stenosis of carotid or vertebro-basilar arteries  Contraindication to and precaution in use of tocilizumab:  Treatment with any investigational agent within 12 weeks (or 5 half-lives of the investigational drug, whichever was longer) of screening Previous treatment with cell-depleting therapies, including investigational agents,including but not limited to Campath (alemtuzumab), anti-CD4, anti-CD5, anti-CD3, anti-CD19, and anti-CD20 Treatment with IV gamma globulin or plasmapheresis within 24 weeks of baseline Previous treatment with alkylating agents, such as chlorambucil, or with total lymphoid irradiation Previous treatment with TCZ Immunization with a live/attenuated vaccine within 4 weeks prior to baseline or simultaneously with tocilizumab treatment Treatment with hydroxychloroquine, cyclosporine A, azathioprine, or mycophenolate mofetil (MMF) within 4 weeks of baseline Treatment with etanercept within 2 weeks; infliximab, certolizumab, golimumab,abatacept, or adalimumab within 8 weeks; or anakinra within 1 week of baseline Previous treatment with tofacitinib Treatment with cyclophosphamide within 24 weeks of baseline History of severe allergic or anaphylactic reactions to human, humanized, or murine monoclonal antibodies or to prednisone Evidence of serious uncontrolled concomitant cardiovascular, nervous system, pulmonary (including obstructive pulmonary disease), renal, hepatic, endocrine (including uncontrolled diabetes mellitus), psychiatric, osteoporosis/osteomalacia, glaucoma, corneal ulcers/injuries, or gastrointestinal disease Current liver disease, as determined by the investigator History of diverticulitis, diverticulosis requiring antibiotic treatment, or chronic ulcerative lower GI disease such as Crohn's disease, ulcerative colitis, or other symptomatic lower GI conditions that might predispose a patient to perforations Known active current or history of recurrent bacterial, viral, fungal, mycobacterial, or other infections (including but not limited to tuberculosis [TB] and atypical mycobacterial disease, hepatitis B and C, and herpes zoster, but excluding fungal infections of the nail beds) Any major episode of infection requiring hospitalization or treatment with IV antibiotics within 4 weeks of screening or oral antibiotics within 2 weeks of screening Active TB requiring treatment within the previous 3 years Patients treated for TB with no recurrence within 3 years and patients treated for latent TB within 3 years were eligible. Primary or secondary immunodeficiency (history of or currently active) Evidence of malignant disease or malignancies diagnosed within the previous 5 years (except basal and squamous cell carcinoma of the skin or carcinoma in situ of the cervix uteri that had been excised and cured) History of alcohol, drug, or chemical abuse within 1 year prior to screening Body weight >150 kg Serum creatinine >1.4 mg/dL (124 µmol/L) in female patients and 1.6 mg/dL (141 µmol/L) in male patients Alanine aminotransferase (ALT) or aspartate aminotransferase (AST)× 3 Upper limit of normal (ULN)> Platelet count < 100 109/L (100,000/mm3) Hemoglobin < 85 g/L (8.5 g/dL; 5.3 mmol/L) White blood cells <3.0 x109/L (3000/mm3) Absolute neutrophil count < 2.0 x 109/L (2000/mm3) Absolute lymphocyte count < 0.5 X 109/L (500/mm3) Positive hepatitis B surface antigen or hepatitis C antibody Contraindication to aspirin, clopidogrel, steroids use, rifampicin and/or isoniazid Major surgery within 8 weeks prior to screening or planned major surgery within 12 months after randomization, except arterial thrombectomy if necessary for ischemic stroke Transplanted organs (except corneal transplant performed more than 3 months prior to screening) Inability to provide informed consent Participation in another interventional research