The purpose of this study is to evaluate the efficacy and tolerability of BVT.115959 in diabetic patients with neuropathic pain who are either not on analgesia or are on stable analgesia in the month prior to entering the study.

The planned study is an exploratory study which aims to provide proof of the efficacy of BVT.115959 in the reduction of the symptoms of pain. Thus, the primary objective is to evaluate the anticipated analgesic properties of BVT.115959 in patients with diabetic neuropathic pain and to confirm its activity against placebo.

The study will evaluate the efficacy and tolerability of oral BVT.115959 7 mg administered three times a day (t.i.d.) versus a matching placebo in diabetic patients with neuropathic pain who are either not on analgesia or are on stable analgesia in the month prior to entering the study and who are being maintained on stable analgesia throughout the study. Eligible subjects will be randomized in a ratio of 2:1 (BVT.115959: placebo).

The study consists of a 1-week screening/baseline period, a 4-week treatment period and a 1 week follow-up period.

Inclusion Criteria:

• A diagnosis of type 1 or 2 diabetes mellitus and documented painful, symmetrical, sensorimotor polyneuropathy for at least 6 months
• Either no analgesic medication or on stable analgesic medication for at least 4 weeks

Exclusion Criteria:

• Female patients who are fertile and of child-bearing potential
• Clinically significant or unstable hepatic, respiratory, renal, hematologic, cardiovascular or peripheral vascular disease
• Painful conditions that may confound the evaluation of neuropathic pain