Cortico-dependence is frequent in giant cell arteritis patients, and no drugs has proved its ability to prevent corticodependence. Hydrocychloroquine is a well tolerated immunomodulatory drug that may have a corticosteroid sparing potential according to immuno-pharmacological and clinical data. We have designed a multcentric double blind versus placebo randomized controled trial to assess the corticosteroid sparing effect of hydroxychloroquine in non complicated giant cell arteritis.