A Study to Evaluate the Efficacy, Safety, and Tolerability of JNJ-42160443 in Patients With Neuropathic Pain (Postherpetic Neuralgia and Post-traumatic Neuralgia)

Inclusion Criteria: Patients diagnosed with postherpetic neuralgia or post-traumatic neuralgia and who have chronic neuropathic pain (pain persistent for \> 6 months) that is moderate to severe; Currently taking pain medication but are not adequately controlled by standard of care or are not currently taking pain medications because intolerable to, or not willing to use, standard of care. Exclusion Criteria: History of a separate pain condition (e.g., joint osteoarthritis) that is more severe than pain due to diagnosis of PHN or post-traumatic neuralgia * Patients with post-traumatic neuralgia that are characteristic of complex regional pain syndrome Type I * Patients with lumbar-sacral radiculopathy, failed low-back surgery, or spinal cord injury * Patient whose nerve injury or pain is expected to recover in the next 4 months * Patients with evidence of another neuropathic pain not under study, such as pain resulting from diabetic painful neuropathy, sensory neuropathies or pain caused by radiation, chemotherapy, alcohol, HIV infection * Other peripheral neuropathy, paresthesia, or dysesthesia, or any other previously diagnosed neurologic condition causing the above noted symptoms that is not related with the PHN or post-traumatic neuralgia under the study * Women who are pregnantHistory of a separate pain condition (e.g., joint osteoarthritis) that is more severe than pain due to diagnosis of PHN or post-traumatic neuralgia; Patients with post-traumatic neuralgia that are characteristic of complex regional pain syndrome Type I; Patients with lumbar-sacral radiculopathy, failed low-back surgery, or spinal cord injury; Patient whose nerve injury or pain is expected to recover in the next 4 months; Patients with evidence of another neuropathic pain not under study, such as pain resulting from diabetic painful neuropathy, sensory neuropathies or pain caused by radiation, chemotherapy, alcohol, HIV infection; Other peripheral neuropathy, paresthesia, or dysesthesia, or any other previously diagnosed neurologic condition causing the above noted symptoms that is not related with the PHN or post-traumatic neuralgia under the study; Women who are pregnant or breast-feeding; Type I or Type II diabetes.