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

The purpose of this study is to evaluate the analgesic efficacy, safety and tolerability of multiple doses of JNJ-42160443 when administered as a single, subcutaneous injection every 28 days to patients with diabetic painful neuropathy (a disease condition in diabetic patients that affects all peripheral nerves including pain fibers, motor neurons and the autonomic nervous system).

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.

Eligibility Criteria:
Inclusion Criteria:

* Chronic neuropathic pain (pain persistent for greater than 6 months) that is moderate to severe in the opinion of the investigator
* Currently taking neuropathic pain medication limited to maximal allowed doses according to guidelines provided, but are not adequately controlled by standard of care
* Currently not taking neuropathic pain medications because they are intolerable to, or not willing to use, standard of care
* Mean average pain intensity score of at least 5, but less than 10, over 7 consecutive days on an 11-point numerical rating scale
* Pain due to bilateral peripheral neuropathy caused by type 1 or type 2 diabetes mellitus
* Required to have stable glycemic control

Exclusion Criteria:

* Patients with severe diabetic neuropathy defined by severe autonomic dysfunction or blood pressure instability Separate pain condition (e.g., joint osteoarthritis) that is more severe than their pain due to their diagnosis of Diabetic Peripheral Neuropathy
* Patients with evidence of another neuropathic pain not under the study, such as pain resulting from post-traumatic neuralgia, post-surgical neuropathy, complex regional pain, sensory neuropathies or pain caused by radiation, chemotherapy, alcohol, Human Immunodeficiency Virus (HIV) infection
* Major surgeries, trauma, and non-healing wounds/ulcers within 3 months prior to study medication
* History of severe traumatic brain injury within the past 15 years
* Other peripheral neuropathy, parasthesia or dyesthesia or previously diagnosed neurological condition causing these symptoms not related with diabetic painful neuropathy under study