Pharmacokinetics of Fentanyl Following Intravenous and Oral Routes of Administration in Healthy Volunteers
The purpose of the study is to compare the pharmacokinetics of fentanyl following i.v. and oral administration in healthy volunteers, and to assess the bioavailability of fentanyl following oral administration. Moreover, safety is assessed.
Drug: Fentanyl citrate; Naltrexone; Naloxone
|Study Design:||Allocation: Randomized
Endpoint Classification: Pharmacokinetics Study
Intervention Model: Crossover Assignment
Masking: Open Label
Primary Purpose: Treatment
|Official Title:||Pharmacokinetics of Fentanyl Citrate Following Intravenous (i.v.) and Oral Routes of Administration in Healthy Subjects|
- Evaluate the pharmacokinetics of fentanyl citrate following i.v. and oral routes of administration in healthy volunteers, and to assess the absolute bioavailability of fentanyl citrate following oral administration.
- Assessment of safety. Vital signs, Physical examination, clinical laboratory tests, and electrocardiogram were performed at screening and study termination. Additionally, vital signs were recorded on Days 1 and 2 of both treatment periods.
|Study Start Date:||April 2003|
|Study Completion Date:||May 2003|
Fentanyl, is an opioid (morphine-like) drug, that has been demonstrated to be an effective pain-killer medication by the i.v. and transdermal (through skin) routes. Fentanyl is used just before, during, and after surgery for its sedative and pain-relieving actions. In addition, fentanyl is currently marketed for transdermal use (Duragesic fentanyl transdermal patch) for the management of chronic pain. The information on the bioavailability of fentanyl solution, following the oral route of administration, is sparse. This is a single-center, randomized (study drug assigned by chance), open-label, 2-treatment, 2-period, crossover study. Healthy volunteers were randomly assigned to 1 of the 2 treatment sequences (AB or BA) with a washout period of 6 to 14 days between treatments. The washout period commenced the day of dosing, after drug administration. Prior to the first treatment period, each healthy volunteer was challenged with naloxone to ensure that he/she was not dependent on morphine-like drugs. A negative naloxone challenge test was required for the healthy volunteer to be eligible for participation in the study. Each healthy volunteer received a 50 mg naltrexone tablet starting 14 hours before dosing and then twice daily ending 24 hours after dosing to block the fentanyl effects. Blood samples were collected, from the arm opposite to the 1 selected for fentanyl i.v administration, for determination of blood fentanyl levels at the scheduled time points. Pulse, blood pressure, breathing rate, body temperature were recorded to monitor the safety. The healthy volunteers were monitored for respiratory depression every 30 minutes during sleep periods. The healthy volunteers remained in the clinic throughout the blood sample collection periods, and were monitored for adverse events throughout the study.
Treatment A: 300 mcg fentanyl citrate administered i.v. over 15 minutes. The 300 mcg (6 mL) i.v. solution was diluted and infused at a rate of 1 mL/minute. Treatment B: 1 mg fentanyl citrate solution administered orally. One mg fentanyl citrate was ingested in 20 mL solution; Naltrexone (50 mg) was administered orally to each healthy volunteer in both periods starting 14 hours before dosing, and twice daily through 24 hours post-dose.