Transdermal fentanyl versus sustained release oral morphine in strong-opioid naïve patients with chronic low back pain.

STUDY DESIGN: Open, randomized, parallel group multicenter study.

OBJECTIVES: To compare the efficacy and safety of transdermal fentanyl (TDF) and sustained release morphine (SRM) in strong-opioid naïve patients with chronic low back pain (CLBP).

SUMMARY OF BACKGROUND DATA: Most studies of TDF and SRM have involved patients already receiving strong opioids. This is the first large-scale study focusing on strong-opioid naïve patients with CLBP.

METHODS: Adults with CLBP requiring regular strong opioid therapy received either TDF or SRM for 13 months. Starting doses were 25 microg/hr fentanyl patches every 72 hours or 30 mg oral morphine every 12 hours. Doses were adjusted according to response. Participants assessed pain relief and bowel function using weekly diaries. Other assessments, including quality of life, disease progression, and side effects, were made by patients and investigators.

RESULTS: Data from 680 patients showed that TDF and SRM provided similar levels of pain relief, but TDF was associated with significantly less constipation than SRM, indicating a greater likelihood of satisfactory pain relief without unmanageable constipation for patients receiving TDF. Other ratings were similar for TDF and SRM, but TDF provided greater relief of pain at rest and at night.

CONCLUSIONS: TDF and SRM provided equivalent levels of pain relief, but TDF was associated with less constipation. This study indicates that sustained-release strong opioids can safely be used in strong-opioid naïve patients.