Study to Test the Effectiveness of Controlled-Release OROS® Hydromorphone HCl Compared to Placebo in Patients With Chronic Low Back Pain

Inclusion Criteria 1. Patients must have been provided with written consent to participate in the study prior to any study procedures, and must understand that they are free to withdraw from the study at any time. 2. Patients who can speak, read, write, and understand English, and must be able to read and understand the consent form, complete study-related procedures, and communicate with the study staff. 3. Male and female patients aged 18-75 years, inclusive. 4. Documented diagnosis of moderate to severe chronic low back pain that must have been present 5. Patients who are classified as non-neuropathic (Class 1 and 2) or neuropathic (Class 3, 4, 5 and 6) of lower back pain based on the Quebec Task Force Classification of Spinal Disorders will be enrolled for this study. 6. Patients who require daily scheduled opioid analgesics for low back pain for at least 2 months prior to the screening visit. 7. Patients with a daily opioid requirement of ≥ 60 mg oral morphine equivalent (≥ 12 mg hydromorphone), but ≤ 320 mg morphine (≤ 64 mg hydromorphone) per day within the 2 months prior to the screening visit. 8. Patients who, in the Investigator's opinion, are on a stable dose (≥ 2 weeks) of all prior analgesics (both opioid and non-opioid) prior to the screening visit. 9. Female subjects of childbearing potential including those who have had a tubal ligation surgery but excluding those who have not experienced a menstrual period for a minimum of 2 years, must have a negative serum pregnancy test at screening visit, and must consent to utilize a medically acceptable method of contraception throughout the entire study period including the washout period and for 1 week after the study is completed. Exclusion Criteria 1. Patients with an active diagnosis of fibromyalgia, complex regional pain syndrome (including reflex sympathetic dystrophy or causalgia), acute spinal cord compression, severe or progressive lower extremity weakness or numbness, bowel or bladder dysfunction as a result of cauda equina compression, diabetic amyotrophy, meningitis, diskitis, back pain because of secondary infection or tumor, or pain caused by a confirmed or suspected neoplasm. 2. Patients who have undergone a surgical procedure for back pain within 6 months prior to the screening visit. 3. Patients who have had nerve or plexus block, including epidural steroid injections or facet blocks, within 1 month prior to the screening visit. 4. Patients with any other chronic pain condition that…