A dose titration study of fentanyl buccal soluble film for breakthrough cancer pain in Taiwan

Background: Fentanyl buccal soluble film (FBSF), a new formulation of fentanyl, is developed for the treatment of breakthrough pain (BTP) in opioid-tolerant patients with cancer. Aims: This study aimed to assess the feasible dose range of FBSF required for Taiwanese population. Methods and results: This was an open-label, multicenter, noncomparative study. Cancer patients who were aged 20 years or older and had a stable regimen equivalent to 60 to 1000 mg/day of oral morphine, 20 to 120 mg/day of intravenous morphine, or 25 to 300 μg/h of transdermal fentanyl for at least 1 week were enrolled. The primary endpoint was the feasible dose range of FBSF. Secondary endpoints included difference in pain intensity at 30 minutes (PID30), percentage of episodes requiring rescue medication, and overall satisfaction. Adverse events (AEs) and serious AEs (SAEs) were recorded for safety measurements. The final effective dose in the per-protocol (PP) population (n = 30) ranged from 200 to 800 μg, of which 26 subjects (86.7%) achieved an effective dose range of 200 to 400 μg. Among the 283 BTP episodes recorded in the maintenance period, the mean PID30 was 4.0, and only 13 events (4.6%) required rescue medication. For 63.6% of the BTP episodes, patients rated their satisfaction as good to excellent. Only 5% of AEs were considered drug-related. Conclusions: Individualized dose titration is recommended for BTP management for patients' benefit. Overall, FBSF was effective and well tolerated and was positively correlated with patients' background opioid dose for persistent pain management.