This study will compare the efficacy and the safety of ABT-894 (1mg, 2mg or 4mg capsules) administered BID to placebo in the treatment of DNP. Another treatment arm will be Duloxetine 60mg administered once daily (QD). Approximately 275 subjects will be enrolled into the study at approximately 50 sites in both the United States and Europe. The study will be divided into the following periods: Screening/Washout (21 days) followed by a Baseline Visit, an 8-week Treatment Period and a 1-week Follow-up Visit.

Inclusion Criteria:

• If female, subject is either postmenopausal for at least two (2) years or surgically sterile or is practicing at least one (1) method of birth control.
• If female, subject must have negative results for pregnancy tests.
• The subject must have a diagnosis of diabetes mellitus (Type 1 or Type 2) and a diagnosis of DNP.
• Subject's DNP must be present for a minimum of six (6) months and should have begun in the feet with relative symmetrical onset.
• Subject has an HgbA1c <= 9. Subjects who have an HgbA1c > 9 and <= 11 may be included in the study.
• If male, the subject is surgically sterile (vasectomy), is sexually inactive, or is using a barrier method (condom) of birth control for the duration of the study and for 7 days following the last dose of study drug.

Exclusion Criteria:

• The subject has failed previous treatment with duloxetine for DNP.
• Subject has a diagnosis of narrow-angle glaucoma.
• Subject has a history of an allergic reaction or intolerance to duloxetine, acetaminophen, or any other NNR agonist.
• Subject has a diagnosis of fibromyalgia that requires treatment.
• Subject has a functioning implanted medical device (spinal cord stimulator, intrathecal pump or peripheral nerve stimulator) for the treatment of neuropathic pain.
• Subject has a history of seizures (febrile may be ok) or major depressive episode within the past two (2) years or major psychiatric disorder including bipolar disorder, schizophrenia or borderline personality disorder.
• Subject has a history of myocardial infarction (MI) within six (6) months of the Screening Visit.
• Subject has unstable angina.
• Subject has ventricular arrhythmia requiring anti-arrhythmic therapy.
• Subject has undergone a cardiac revascularization procedure within 30 days of Screening.
• Subject has uncontrolled hypertension (HTN) defined as a systolic blood pressure (BP) >= 160 and/or a diastolic blood pressure (BP) >= 100 at Screening and/or Baseline.
• Subject has a clinically significant abnormal ECG at Screening
• Subject has an active malignancy of any type or has been diagnosed with or treated for cancer within the past 5 years.
• Subject has a positive result for drugs of abuse at Screening with the exception of a positive result for a known prescribed medication.
• Subject's screening laboratory results show hepatitis A, B or C.
• Subject has a known or suspected history of Human Immunodeficiency Virus (HIV).