Fentanyl sublingual spray for breakthrough cancer pain in patients receiving transdermal fentanyl.

AIM To investigate the relationship between effective fentanyl sublingual spray (FSS) doses for breakthrough cancer pain (BTCP) and around-the-clock (ATC) transdermal fentanyl patch (TFP). METHODS Adults tolerating ATC opioids received open-label FSS for 26 days, followed by a 26-day double-blind phase for patients achieving an effective dose (100-1600 µg). RESULTS Out of 50 patients on ATC TFP at baseline, 32 (64%) achieved an effective dose. FSS effective dose moderately correlated with mean TFP dose (r = 0.4; p = 0.03). Patient satisfaction increased during the study. Common adverse event included nausea (9%) and peripheral edema (9%). CONCLUSION FSS can be safely titrated to an effective dose for BTCP in patients receiving ATC TFP as chronic cancer pain medication. ClinicalTrials.gov identifier: NCT00538850.