Objective: The objectives of the study were to determine the absolute bioavailability of fentanyl from fentanyl buccal soluble film, estimate the percentage of a fentanyl dose absorbed through the buccal mucosa, and compare the bioavailability of equivalent doses administered either as single or multiple dose units.
Design: Open-label, randomized, four-period, Latin-square crossover pharmacokinetic study.
Setting: Inpatient phase 1 unit.
Patients: Twelve healthy volunteers. Interventions. Injectable fentanyl citrate (200 microg) administered by intravenous infusion, injectable fentanyl citrate (800 microg/16 mL) administered orally, and fentanyl buccal soluble film (800 microg) administered as a single film and as four separate 200 microg films simultaneously.
Outcome measures: Plasma concentrations after fentanyl dosing; pharmacokinetic parameters.
Results: The two buccal film treatments were bioequivalent and both had an absolute bioavailability of 71%. The percentage of an administered dose absorbed through the buccal mucosa was calculated to be 51%.
Conclusions: Fentanyl buccal soluble film effectively delivers a high percentage of the administered fentanyl dose and nearly identical plasma profiles are obtained when equivalent doses are delivered by single or multiple dosage units.