Efficacy and Safety Study of Probucol in Patients With Diabetic Nephropathy

Inclusion Criteria: 1. The subject is male or female diagnosed with type 2 diabetes mellitus and must be aged 20 to 75 years at the time of screening visit 2. Urinary albumin excretion \> 300 mg/g Cr at screening visit 3. Subjects administered ACEI or ARB without changing dosage prior to 3 months at the screening visit (if subjects administered ACEI or ARB) 4. Subjects administered statins without changing dosage prior to 3 months at the screening visit(if subjects administered statins) or subjects have no plan to administered to statin(if subjects is not administered statin) 5. 15 mL/min ≤ eGFR ≤ 90 mL min 6. Subjects must be willing and able to give signed and dated written informed consent. Exclusion Criteria: 1. Type 1 DM or gestational diabetes 2. Subjects on Renal replacement therapy or Renal transplantation prior to Screening visit 3. Ventricular arrhythmia (multiple and multifocal premature ventricular contractions) 4. Cardiac damage (abnormally levels of Troponin I) 5. Subject with medical history of cardiac syncope or primary syncope 6. Has condition that may prolong QTc interval (for man QTc interval\>450msec, for woman QTc interval\>470msec) at screening 7. Pregnant or lactating woman before randomization 8. Inflammatory bowel disease (ulcerative colitis, Crohn's disease) 9. Cholestasis 10. Congestive heart failure 11. Subjects with a myocardial infarction, Unstable angina, or cerebral infarction within the latest 6 months 12. Subjects has a diagnosis of NYHA grade III-IV status 13. AST or ALT is 3.0 times higher than the upper limit of the normal range 14. Active hepatitis Or Liver cirrhosis 15. Subjects with Hyperkalemia (K\>5.5 mEq/L) 16. Subjects with Renal Artery stenosis 17. Subjects with Malignancy within the 5 years at the time of screening visit(except for treated Basal cells carcinoma or squamous cell carcinoma) 18. Urinary tract disease (urinary tract infection, Neurogenic bladder) 19. Kidney disease (nephritis, chronic glomerulonephritis or polycystic kidney disease) 20. Has an allergic history to probucol 21. HbA1c \> 9% 22. Systolic blood pressure ≥ 160 mmHg or Diastolic blood pressure ≥ 100 mmHg 23. Subjects taken probucol within 3 months prior to Screening 24. The subject has received an investigational product or biological agent within 3 months prior to screening 25. Subjects otherwise judged by the investigator or sub investigator to be inappropriate for inclusion in the trial