A substudy included 46 patients from DA VINCI ( a randomized , double-masked Phase 2 study ) receiving either laser , 0.5 mg IAI every 4 weeks , 2 mg IAI every 4 weeks , 2 mg IAI every 8 weeks after 3 monthly doses ( 2q8 ) , or 2 mg IAI as-needed after 3 monthly doses for 52 weeks .