A Study of a Topical Patch (AB001) in Patients With Chronic Low Back Pain

Inclusion Criteria: 1. Are generally healthy males or non-pregnant females, 18 to 75 years of age. 2. Have a body mass index (BMI) ≤35. 3. Have chronic low back pain for at least 3 months. 4. Have low back pain that is located inferior to the twelfth thoracic vertebra (T-12). 5. Back pain classified, using the Quebec Task Force system, as either Class 1 or Class 2. 6. Currently require use of analgesics for lower back pain (required at least 3 days per week for at least the last 4 weeks). 7. Have a score of 30 mm or greater on the visual analog scale (VAS) and a score of 2, 3, or 4 on the Subject Global Assessment (SGA) of Back Pain Scale at Screening. 8. Are willing to discontinue current analgesics for the 3 to 15 day washout period. 9. Have an increase of at least 10 mm or more from the score at Screening and an absolute score of 50 mm or more on the VAS (ie, VAS ≥ 50 mm) and a score of 3 or 4 on the SGA of Back Pain Scale at Baseline. 10. If female, are: 1).Of non-childbearing potential or have a confirmed clinical history of sterility or, 2).Of childbearing potential, must be willing to use effective contraception at trial entry and until completion. 11. Are willing to provide written informed consent. Exclusion Criteria: 1. Have chronic lower back pain (CLBP) due to any of the following pathologies: infection, neoplasia, metabolic or structural disturbance of spine, lumbar radiculopathy, osteoporosis, hip dysplasia, inflammatory arthritis, ankylosing spondylitis, Paget's disease, cauda equine syndrome, gout, pseuodgout, fibromyalgia, post-surgical pain. 2. Have low back pain caused by major trauma. 3. Have excess hair, tattoo(s), or other dermatologic conditions in the patch application area that might interfere with efficacy evaluation. 4. Have had surgery for low back pain within the previous 6 months. 5. Have had clinical depression within 2 years or are currently undergoing treatment for depression; 6. Have a hypersensitivity to non-steroidal anti-inflammatory drugs (NSAIDs, including aspirin) or hypersensitivity to acetaminophen. 7. Have used opioids within 72 hours prior to the Baseline / Day 1 visit or during the course of the study. 8. Have used oral or injected corticosteroids chronically or intermittently within the past 60 days (oral), or 90 days (injected). 9. Are a current drug or alcohol abuser. 10. Are pregnant, plan to become pregnant during the study, or are breastfeeding. 11. Have a pending workman's compensation claim, litigation, …