This is a phase 4, multicenter, randomized, double-blind, parallel-group, comparative study using placebo (Treatment Period I) and a phase 4, multicenter, open-label, long-term study (Treatment Period II) to evaluate the efficacy and safety of SYR-472 when administered at a dose of 100 mg as an add-on to insulin therapy in patients with type 2 diabetes mellitus and inadequate glycemic control despite treatment with insulin preparations in addition to diet and/or exercise therapy.
The purposes of this study is to evaluate the efficacy and safety of SYR-472 when administered at a dose of 100 mg once weekly as an add-on to insulin therapy compared with placebo in patients with type 2 diabetes mellitus and inadequate glycemic control despite treatment with insulin preparations in addition to diet and/or exercise therapy; and to evaluate the long-term efficacy and safety of SYR-472 when administered at a dose of 100 mg once weekly as an add-on to insulin therapy in patients with type 2 diabetes mellitus and inadequate glycemic control despite treatment with insulin preparations in addition to diet and/or exercise therapy.