Open-label study of the safety and effectiveness of long-term therapy with extended-release tramadol in the management of chronic nonmalignant pain.

Background: Tramadol ER* is a once-daily oral analgesic for management of moderate-to-moderately severe chronic pain in adults who require around-the-clock treatment of pain. This study evaluated long-term safety of tramadol ER and effectiveness outcomes in the management of chronic, nonmalignant pain.

Methods: Patients enrolled directly for approximately 1 year of open-label tramadol ER treatment if they had chronic, nonmalignant pain (n = 919), or 'rolled over' for 38 weeks of open-label tramadol ER treatment if they completed either of two 12-week, placebo-controlled studies of tramadol ER for low back pain (n = 72) or osteoarthritis (n = 61). Tramadol ER was titrated to a dose of 300 mg once daily (patients >or= 75 years) or 300-400 mg once daily (patients < 75 years).

Results: A total of 257 (24%) patients completed the study. Common adverse events, regardless of treatment relationship, were nausea, dizziness (excluding vertigo), and constipation. Mean scores for current pain intensity (from 0 = no pain to 100 = extreme pain) and least, worst, and average pain intensity over the past week improved at every post-baseline visit. At each post-baseline visit, > 50% of patients provided a global assessment rating of good, very good, or excellent. Study limitations were mandatory titration to 400 mg in some patients, concomitant analgesic therapy as a confounding variable, and lack of a placebo comparator.

Conclusions: Individualized dose titration and limiting once-daily therapy with tramadol ER to the maximum recommended daily dose of 300 mg may balance tolerability and analgesic effects of tramadol ER in patients with chronic, nonmalignant pain.