Efficacy of Tocilizumab for the Treatment of Acute AION Related to GCA

Inclusion Criteria:

1. Age of 50 years or older
2. Social insurance
3. Diagnosis of AION, characterized by sudden and painless loss of vision, of less thanone week, accompanied by pallid swelling of the optic disc
4. Sudden permanent visual loss due to AION, of less than one week
5. Diagnosis of GCA based on the 1st (age ≥ 50 years) and the 3rd (Diagnosis of AION)criteria and at least one among the following :

• One unequivocal symptom among: New onset localized headache, scalp or temporalartery tenderness, otherwise unexplained mouth or jaw pain under mastication, orunequivocal symptoms of polymyalgia rheumatic (shoulder and/or hip girdle painassociated with inflammatory stiffness).
• Elevated erythrocyte sedimentation rate (≥ 50 at 1 hour) or C-reactive protein (≥ 10 mg/l), otherwise unexplained
• Abnormal artery biopsy Biopsy specimen with artery showing vasculitischaracterized by a predominance of mononuclear cell infiltration or granulomatousinflammation, usually with multinucleated giant cells.
• Evidence of large or medium-size vessel vasculitis at ultrasound, magneticresonance angiography, computed tomography angiography, or positron emissiontomography-computed tomography.

Exclusion Criteria:

• Other ocular involvements related to GCA (central retinal artery occlusion, posteriorischemic optic neuropathy, transient ocular manifestations, occipital stroke), if notassociated with AION
• Biological targeting therapy within 3 months preceding the study
• Evidence of active infection
• History of any malignant neoplasm except adequately treated basal or squamous cellcarcinoma of the skin or solid tumors treated with curative therapy and disease-freefor at least 5 years
• History of recurrent infections, diverticulitis or intestinal ulceration and ASAT/ALAT > 5 * upper limit of normal, according to the Summary of Product Characteristics oftocilizumab
• Contraindication to steroids and/or aspirin administrated in the treatment
• Breastfeeding women and women with childbearing potential without highly effectivecontraception.
• Pregnant or nursing (lactating) women confirmed by a positive βHCG laboratory test atthe inclusion
• Women of child-bearing potential, defined as all women physiologically capable ofbecoming pregnant, unless they are using highly effective methods of contraceptionduring study treatment and for 3 months after the last administration of tocilizumab.
• Cytopenia, as defined by platelet count < 100 × 109/L (100,000/mm3), hemoglobin < 85g/L (8.5 g/dL; 5.3 mmol/L), absolute neutrophil count < 2.0 × 109/L (2000/mm3),absolute lymphocyte count < 0.5 × 109/L (500/mm3)
• Insufficient liver function (Child Pugh C )
• Insufficient kidney function, as defined by a serum creatinine of more than 3 mg/dL orcreatinine clearance of 20 ml/min or less
• Patients with previously untreated tuberculosis, previously known TDM/radiographicevidence suggestive of active and/or sequellar tuberculosis
• HIV infected, hepatitis C infected, or a positive hepatitis B surface antigen if knownbefore study inclusion
• Contraindication to and precaution in use of tocilizumab according to the summaryproduct description
• Inability to provide informed consent