The safety and efficacy of fentanyl iontophoretic transdermal system compared with morphine intravenous patient-controlled analgesia for postoperative pain management: an analysis of pooled data from three randomized, active-controlled clinical studies.

BACKGROUND: Postoperative pain is often managed using IV patient-controlled analgesia (PCA). In this analysis of pooled data, we compared the safety and efficacy of the fentanyl iontophoretic transdermal system (ITS) with morphine IV PCA. METHODS: Data were obtained from three multicenter, randomized, active-controlled trials (N = 1941). The primary efficacy measure was success (“good”/“excellent” ratings) on the 24-h patient global assessment of the method of pain control. Pain intensity, relative dosing ratios, discontinuation rates, and adverse events were assessed. Efficacy was evaluated across age, surgery type, and body mass index (BMI). RESULTS: Comparable percentages of patients reported success on the 24-h patient global assessment of the method of pain control (fentanyl ITS, 80.5%; morphine IV PCA, 81.0%; difference = −0.5%; 95% confidence interval, −4.0% to 3.0%). Mean last pain intensity scores in the first 24 h were comparable (fentanyl ITS, 3.1; morphine IV PCA, 3.0; difference = 0.07; 95% confidence interval, −0.14 to 0.29). Relative dosing ratios of fentanyl to morphine overall and in subpopulations (age, BMI) were comparable over 6, 12, and 24 h. Fentanyl ITS was equally effective when compared with morphine IV PCA for patient subpopulations (age, surgery type, and BMI). Discontinuation rates and the incidence of adverse events were similar between groups. CONCLUSIONS: These pooled data represent one of the largest head-to-head comparisons of fentanyl versus morphine in a postoperative acute pain setting. Results suggest that fentanyl ITS is effective across subpopulations defined by age and BMI, and support a consistent safety and efficacy profile of fentanyl delivered by fentanyl ITS for postoperative pain management.