Long-term tolerability of fentanyl effervescent buccal tablets: Interim analysis in patients with cancer-related breakthrough pain

Abstract

8567 Background: Fentanyl effervescent buccal tablets (FEBT) are designed to enhance the rate and efficiency of fentanyl absorption through the buccal mucosa. Results reported here represent a pre-specified interim analysis of an open-label safety and efficacy study of FEBT in opioid-tolerant patients with cancer-related breakthrough pain (BTP). Methods: Patients with cancer-related BTP receiving around-the-clock and supplemental opioids were eligible to enroll. Patients who had participated in a previous dose-titration study of FEBT enrolled directly into the 1-year phase; new patients entered a titration phase to determine an effective FEBT dose before entering the 1-year phase. An effective FEBT dose was defined as the dose needed to provide adequate analgesia for BTP. By October 3, 2005, 170 patients (aged 24 to 95 years) received FEBT (100–800 μg) and had documented safety data. Results: Of the 112 new patients, 70.5% identified an effective FEBT dose and were eligible for enrollment. In the long-term phase, patients received FEBT for a mean of 109.8 days; 8% at 100 μg, 15% at 200 μg, 23% at 400 μg, 25% at 600 μg, and 29% at 800 μg. The FEBT dose remained reasonably stable during the long-term phase, but 43 patients had a dose increase and 6 had a dose decrease at the discretion of the investigator. Only 2 patients required a change in the FEBT dose because of tolerability. The most common adverse events (AEs) are given in the table. The incidence of AEs did not correlate with the effective FEBT dose. The 42 patient deaths that occurred were all attributed to cancer-related pathology or the progression of cancer. Conclusions: Overall, FEBT was well tolerated in opioid-tolerant patients with cancer-related BTP. [Table: see text] [Table: see text]