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

• Average pain intensity [ Time Frame: Baseline to Week 13 ] [ Designated as safety issue: No ]
  The mean of the daily evening assessment of average pain intensity is measured by using 11-point numerical rating scale (NRS), where 0 = no pain and 10 = pain as bad as the patient can imagine.
  
  

• Pain at its worst [ Time Frame: Baseline to Week 13 ] [ Designated as safety issue: No ]
  The assessment of pain at its worst in the past 24 hours will be performed once daily, in the evening, using an 11-point numerical rating scale (NRS), where 0 = no pain and 10 = pain as bad as the patient can imagine.
  
  
• Brief Pain Inventory [ Time Frame: Up to Week 105 ] [ Designated as safety issue: No ]
  The Brief Pain Inventory short form (BPI-SF) includes 4 items assessing pain intensity (pain intensity subscales) and 7 items assessing how much pain has interfered with daily activities (pain interference subscales). The intensity of pain is assessed with 4 items using an 11-point NRS from 0 = no pain to 10 = higher severity of pain. This assessment will be conducted on daily basis.
  
  
• Neuropathic pain symptom inventory (NPSI) [ Time Frame: Up to Week 105 ] [ Designated as safety issue: No ]
  The NPSI contains 12 questions designed to evaluate the different symptoms of neuropathic pain. The questions make up the following 5 subscales: burning (superficial) spontaneous pain, pressing (deep) spontaneous pain, paroxysmal pain, evoked pain and paresthesia/dysesthesia. Subscale scores can be derived from averaging the scores from the item scores that make up the subscales, ranging from 0 to 10. A total intensity score is the sum of the subscale scores, ranging from 0 to 100. Higher scores indicate worse pain. This assessment will be conducted on daily basis.
  
  
• Patient Global Impression of Change (PGIC) [ Time Frame: Up to week 105 ] [ Designated as safety issue: No ]
  The patient will be asked to rate their change in their neuropathic pain with the following responses: very much improved, much improved, minimally improved, not changed, minimally worse, much worse, or very much worse. This assessment will be conducted on daily basis.
  
  
• Number of patients with adverse events [ Time Frame: Up to week 105 and 26 weeks after the last dose of study medication ] [ Designated as safety issue: Yes ]
  

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.