Efficacy of tocilizumab in refractory giant cell arteritis.

Giant cell arteritis is the most frequent form of vasculitis characterized by a high risk of vascular thrombosis. Major complications are blindness and other vascular ischemia but bowel ischemic involvement is rare. Treatment is based on long-term steroid therapy with numerous side effects. The efficacy of immunosuppressive drugs like azathioprine methotrexate or anti-tumor necrosis factor antibodies appears to be too low to reduce the use of steroids. Th17 lymphocytes and interleukin-6 play an important role in pathogenesis of giant cell arteritis. We report here a case of effective interleukin-6 blocker in the treatment of refractory giant cell arteritis with ileitis and high-dose steroid dependence despite 2 years of treatment with steroids and methotrexate. After infusions of tocilizumab, no relapse at 6 months was found despite the decrease in corticosteroids.