This study is a randomized, parallel, open-label, multicenter, phase IV clinical trial to assess the efficacy and safety of pregabalin and alpha-lipoic acid combination compared with each monotherapy in patients with diabetic peripheral neuropathy for 12 weeks.

Inclusion Criteria:

• aged 19 to 75
• type 2 diabetes mellitus with HbA1c (Hemoglobin A1c) ≤ 10 %
• peripheral (eg. hands, feet) neuropathic pain (eg. abnormal sensations, numbness, pain, etc.) within 3 months (12 weeks)
• diagnosed with diabetic peripheral neuropathy (DPN)
• VAS pain score ≥ 40 mm
• written informed consent

Exclusion Criteria:

• brittle diabetes mellitus
• ALT (Alanine Transaminase), AST (Aspartate Transaminase), CPK (Creatine Phosphokinase) level ≥ 3 times the upper limit of normal (UNL) or active liver disease
• severe renal impairment (eGFR (estimated glomerular filtration rate) < 60 mL/min/ 1.73m2)
• treated with antiepileptic drugs within 1 week at randomization
• other nervous system or neuropathic disorders that may affect pain evaluation
• oral drug administration is not possible, or hypersensitive or allergic to pregabalin, r-thioctic acid tromethamine, thioctic acid, and other excipients
• pregnant, lactating, or childbearing potential
• alcoholics, drug abusers, and patients who are difficult to participate in clinical trials due to psychological and emotional problems
• have participated in other clinical trials within 30 days at screening