This study is to compare the efficacy and safety of pregabalin sustained release tablet and pregabalin immediate release capsule in type II diabetic patients with peripheral neuropathic pain.

Inclusion Criteria:

1. Aged ≥ 19 years, < 75 years
2. VAS score for diabetic peripheral neuropathy pain ≥ 30
3. Patients who have been administering pregabalin immediate release capsule 150 mg/day for more than 4 weeks
4. Type II DM patient and HbA1c ≤ 10 %
5. Written informed consent

Exclusion Criteria:

1. Patient with hypersensitivity to pregabalin
2. Patient on anti-epileptic drugs
3. Patients with pain caused by other factors than diabetic peripheral neuropathy
4. Patients undergoing eGFR <30 mL/min/1.73 m2 (MDRD) at screening
5. AST(Aspartate Aminotransferase) or ALT(Alanine Aminotransferase) level ≥ 3x ULN (upper limit of normal range) or active liver disease
6. Drug-abusing patient
7. Severe depression or uncontrolled abnormal mood and behavioral changes
8. Pregnant and breast-feeding woman
9. Patients who participated in other clinical trials for investigational products within 30 days of screening
10. Patients deemed to be ineligible to participate in the trial by investigator