A Study of Effectiveness and Safety of JNJ-42160443 in Patients With Diabetic Painful Neuropathy

This is a multicenter (study conducted at multiple sites), randomized (the study medication is assigned by chance), double-blind (neither investigator nor the patient knows the treatment that the patient receives), placebo-controlled (an inactive substance that is compared with the study medication to test whether the study medication has a real effect in clinical study), dose-ranging study (study carried out at different doses) to evaluate the analgesic efficacy, safety, and tolerability of multiple doses of JNJ-42160443 in patients with neuropathic pain, followed by a double-blind safety extension and an open-label (all people know the identity of the intervention) safety extension. The study will consist of 5 sequential phases: 1) screening, 2) a 12-week double-blind efficacy, 3) a 40-week double-blind safety extension, 4) a 52-week open-label safety extension, and 5) a 26-week post-treatment/follow-up. After the screening phase, patient randomization will be stratified by current pain medication use (patients who are currently using or who are not currently using permitted pain medication). The planned doses for the double-blind efficacy phase and double blind safety extension phase are placebo, JNJ-42160443 1, 3, or 10 mg administered as a single, subcutaneous injection every 28 days. Safety assessment will include adverse events, injection site evaluations, clinical laboratory tests, electrocardiogram, vital signs, physical examinations, neurological examinations, and joint safety which will be monitored throughout the study. The total study duration (including all the 5 phases) will be approximately 131 weeks.