HP184 in Chronic Spinal Cord Injury Subjects

Inclusion Criteria: Male and female subjects with incomplete (traumatic), chronic (defined as 18 months or more post spinal cord injury) SCI aged 18 to 65 years CSCI must be categorized in classes C or D in the ASIA impairment scale. (C = Incomplete impairment with motor function preserved below the neurological level, and more than half of key muscles below the neurological level have a muscle grade less than 3. D = Incomplete impairment with motor function preserved below the neurological level, and at least half of key muscles below the neurological level have a muscle grade more than or equal to 3). The level of the SCI must be between C4 and T10 (neurological) Subject has a measurable range of motion at the hips, knees and ankles and possesses potential propulsive activity (i.e. no functional contractures) Female subjects of childbearing potential (those who are not surgically sterile or who are less than 2 years postmenopausal) must be using two forms of birth control, including a primary and a secondary form and have a negative pregnancy test immediately prior to treatment. Primary forms of contraception include: tubal ligation, partner's vasectomy, intrauterine devices, birth control pills, and topical/injectable/implantable/insertable hormonal birth control products. Secondary forms of contraception include diaphragms, latex condoms and cervical caps; each must be used with a spermicide. Exclusion Criteria: Any clinical evidence of recent fracture(s) within the last six months prior to study start. Any history of Multiple Sclerosis or peripheral demyelinating disease or neuromuscular disorder. Heart rate of less than 38 or greater than 100 Ashworth spasticity score of 0/4 or 4/4 at the hip or knee. Subject whose medical condition requires mechanical ventilation. Lower motor neuron injury, such as those with conus medullaris or cauda equina injuries. Subject with lower extremity amputation or proximal femorectomy. Subject with pressure ulcers stages 3 and 4. Subject medically or mentally unstable in judgment of Investigator. Subject on tricyclic antidepressants such as nortriptyline, amitriptyline and imipramine. Subject with ASIA motor score of greater than or equal to 92. Subject with ASIA sensory score of greater than or equal to 200. Subject with history of seizure within 2 years prior to study start. Subjects who have participated in a clinical trial involving investigational medication within 30 days prior to administration of HP184 or placebo. Female subjects with positive urine pregnancy test. Female subjects who are breast feeding.