Background and objectives: A number of transmucosal fentanyl formulations have been developed for the management of breakthrough cancer pain (BTCP). Sublingual delivery of fentanyl, formulated as fentanyl sublingual spray, offers the potential for more rapid and greater absorption of fentanyl and associated onset of analgesic effect compared with other formulations. The objective of this study was to assess the efficacy and safety of fentanyl sublingual spray for the treatment of BTCP.
Research design and methods: This was a randomized, double-blind, placebo-controlled phase III trial conducted in opioid-tolerant patients with BTCP. An open-label titration period was followed by a double-blind treatment period during which patients received fentanyl sublingual spray (100-1600 mcg) or placebo.
Clinical trial registration: ClinicalTrials.gov NCT00538850.
Main outcome measures: The primary efficacy measure was summed pain intensity difference at 30 minutes (SPID(30)). Secondary efficacy measures included total pain relief at 30 minutes (TOTPAR(30)) and patient global evaluation of study medication at 30 minutes. Efficacy measures were also assessed at various time points from 5-60 minutes postdose. Adverse events were monitored throughout the study.
Results: A total of 130 patients were treated during the titration period, of whom 98 (75.4%) entered the double-blind period. Relative to placebo, fentanyl sublingual spray significantly improved mean SPID scores from 5 minutes (p = 0.0219) through 60 minutes (p < 0.0001), including the primary endpoint at 30 minutes (p < 0.0001). Fentanyl sublingual spray produced significantly greater pain relief (expressed in terms of TOTPAR) from 5 through 60 minutes (p < 0.0001), and significantly greater global evaluation of treatment effectiveness (p < 0.0001), compared with placebo. During double-blind treatment, the most frequently reported adverse events were nausea (7.1%), hyperhidrosis (5.1%), and peripheral edema (5.1%). Serious adverse events occurred in seven patients (5.4%) during titration and six (6.1%) during double-blind treatment; none were considered related to treatment.
Conclusions: These findings indicate that treatment with fentanyl sublingual spray results in effective relief of BTCP, with a rapid onset of action, and is well tolerated.