The purpose of this study is to evaluate the efficacy of MT-3995 in subjects with diabetic nephropathy, compared with placebo, using urine albumin- to-creatinine ratio (UACR) in the first morning void urine sample as an indicator.

Inclusion Criteria:

• Type 2 diabetes mellitus
• Glycated hemoglobin(HbA1c) values (National Glycohemoglobin Standardization Program : NGSP) ≤10.5%
• estimated glomerular filtration rate(eGFR) of ≥30 mL/min/1.73 m2
• The median UACR of the first morning void urine samples is ≥50 mg/g Cr and <300 mg/g Cr
• Stable blood pressure(diastolic blood pressure (DBP) <100 mmHg and stable systolic blood pressure (SBP) <160 mmHg)

Exclusion Criteria:

• Type 1 diabetes, diabetes resulting from pancreatic injury, or secondary forms of diabetes.

• A diagnosis of non-diabetic renal disease.

• A following serum potassium level.

  • eGFR of 30-59mL/min/1.73m2; serum potassium level of <3.5 or >4.7 mmol/L,
  • eGFR of ≥60mL/min/1.73m2: serum potassium level of <3.5 or >5.0 mmol/L

• symptomatic and clinically significant hypotension(diastolic blood pressure(DBP)<50mmHg and systolic blood pressure(SBP)<110mmHg)

• QT prolongation or torsades de pointes, or, a history or family history of QT prolongation or torsades de pointes

• New York Heart Association (NYHA) Class III or IV heart failure