A Study Comparing the Efficacy and Safety of ABT-652 to Placebo in Subjects With Diabetic Neuropathic Pain

• Neuropathic Pain Symptom Inventory [ Time Frame: 12 weeks ] [ Designated as safety issue: No ]
  Measures severity of common neuropathic pain qualities (burning, pressure, squeezing)
• Patient Global Impression of Change [ Time Frame: 12 weeks ] [ Designated as safety issue: No ]
  Captures the subject's evaluation of his/her overall general impression of feeling since beginning study medication
• Brief Pain Inventory [ Time Frame: 12 weeks ] [ Designated as safety issue: No ]
  Capture the subject's severity of pain and interference
• Neuropathic Pain Impact on Quality of Life Questionnaire [ Time Frame: 12 weeks ] [ Designated as safety issue: No ]
  Captures the subject's assessment of neuropathic pain and the effect it has on the quality of daily life
• EuroQuality of Life - 5 Dimension -5 Level [ Time Frame: 12 weeks ] [ Designated as safety issue: No ]
  Capture's the subject's mobility, self-care, usual activity, pain/discomfort and anxiety/depression

To evaluate the safety and efficacy of ABT-652 compared to Placebo in subjects with diabetic neuropathic pain. People with diabetes can, over time develop nerve damage throughout the body with symptoms such as pain, tingling, or numbness (loss of feeling) in the hands, arms, feet and legs.

A double blind, randomized, active- and placebo-controlled 13-week study. Duloxetine is added to evaluate assay sensitivity.

• Drug: ABT-652 6 mg
  See arm description for more information
  Other Name: ABT-652
• Drug: ABT-652 12 mg
  See arm description for more information
  Other Name: ABT-652
• Drug: ABT-652 12 mg - 18 mg
  See arm description for more information
  Other Name: ABT-652
• Drug: Placebo comparator
  See arm description for more information
  Other Name: Placebo
• Drug: Duloxetine
  See arm description for more information
  Other Name: Duloxetine

• Experimental: ABT-652 6 mg
  ABT-652 capsules - twice daily
  Intervention: Drug: ABT-652 6 mg
• Experimental: ABT-652 12 mg
  ABT-652 capsules twice daily
  Intervention: Drug: ABT-652 12 mg
• Experimental: ABT-652 12 mg - 18 mg
  ABT-652 capsules twice daily
  Intervention: Drug: ABT-652 12 mg - 18 mg
• Placebo Comparator: Placebo
  Placebo capsules twice daily
  Intervention: Drug: Placebo comparator
• Active Comparator: Duloxetine
  Duloxetine capsules once daily
  Intervention: Drug: Duloxetine

Inclusion Criteria

• Subject is between the ages of 18-75 years with a diagnosis of diabetes mellitus and must have a diagnosis of painful distal symmetric diabetic polyneuropathy and presence of ongoing pain due to diabetic peripheral neuropathy for at least 6 months.
• Subject must have a mean average score of greater than 4 on the 24 hour average pain score (0-10 numerical rating scale) prior to the Baseline Visit.
• Subject has been on a medication for diabetic neuropathic pain for the past 3 months.

Exclusion Criteria

• Subject has clinically symptomatic neuropathic pain conditions that cannot be distinguished from Diabetic Neuropathic Pain or interfere with the pain assessments of Diabetic Neuropathic Pain.
• A subject has newly diagnosed or clinically significant medical conditions or mental disorders that would preclude participation or would interfere with Diabetic Neuropathic Pain assessments or other functions.
• Subject has clinically significant abnormalities in clinical laboratory tests.
• Subject has taken an opioid chronically, excluding tramadol within the last 3 months prior to Screening.