Purpose: Sufentanil is a μ-opioid agonist with a high therapeutic index in preclinical studies and no active metabolites, and it is highly lipophilic, thereby enabling a transmucosal route of administration. Rapid distribution from the plasma after IV sufentanil administration results in a short duration of action requiring excessive repeated dosing if used for postoperative analgesia. The sufentanil sublingual tablet system (SSTS) is a handheld, preprogrammed, patient-controlled analgesia system designed to allow patients to self-administer sufentanil 15-μg tablets under their tongue with a 20-minute lockout. The pharmacokinetic (PK) characteristics of sufentanil, administered by different routes of delivery and after single and repeated sublingual (SL) administration, were examined in 2 studies.
Methods: A randomized, open-label, crossover study in healthy subjects evaluated the PK profile of sufentanil 15 μg administered by different routes: IV, SL, buccal (BU), and PO. A second open-label, crossover study in healthy subjects evaluated the PK parameters after single and repeated doses (full SSTS drug cartridge of 40 consecutive SL doses administered every 20 minutes) of a sufentanil 15-μg SL tablet. Doses were self-administered using the SSTS.
Findings: In the route of administration study (n = 25), mean Cmax values were highest with IV administration, and bioavailability values were: SL, 59%; BU, 78%; and PO, 9%. The absorption across the oral mucosa was associated with a median plasma half-time (time from Cmax to 50% of Cmax) that was 25-fold longer (2.5 hours) with SL versus IV administration (0.1 hours). In the single- and repeated-dose study (n = 38), mean AUC0-∞ was 125.5 h · pg/mL, and Cmax was 35.0 pg/mL, with a median Tmax of 0.8 hours after the administration of a single sufentanil SL tablet. With 40 consecutive doses, Cmax was 8-fold higher compared with that of a single dose, and steady state was achieved after the 13th dose. Median plasma half-time after the 40th dose was not statistically longer than that after a single dose (2.7 vs 2.2 hours, respectively), and the median Tmax was 0.3 hours after the last repeated dose.
Implications: These study results support the viability of the SSTS for use in patient-controlled analgesia. The wide range of mean drug concentrations achieved after repeated dosing at 20-minute intervals compared with those with a single dose suggests the flexibility of patient-controlled dosing to meet individual analgesic requirements. The prolonged plasma half-time with SL administration is expected to provide a more appropriate duration of analgesia compared with that of IV administration, and the PK properties of repeated-dose administration support a 20-minute lockout interval.
Keywords: context-sensitive half-time; patient-controlled analgesia; sublingual; sufentanil.
Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.