The primary purpose of this study is to assess the renal protective effect of ipragliflozin in combination with metformin on the percent change of UACR from baseline to 24 weeks against glimepiride in combination with metformin in type 2 diabetes mellitus patients with albuminuria. The secondary purpose of this study is to assess the efficacy, safety and impact on quality of life (QoL) of ipragliflozin in combination with metformin against glimepiride in combination with metformin in type 2 diabetes mellitus patients with albuminuria.