A randomized, open, parallel group, multicenter trial to investigate analgesic efficacy and safety of a new transdermal fentanyl patch compared to standard opioid treatment in cancer pain

A new 72-hour transdermal fentanyl matrix patch has been designed, which has a 35%-50% reduction of the absolute fentanyl content compared with other currently available transdermal fentanyl patches that are using the matrix technology. The new patch has previously been shown to be pharmacokinetically bioequivalent to the marked fentanyl patch. To determine noninferiority in efficacy in cancer patients and to compare safety, a clinical trial comparing the new fentanyl patch with standard oral or transdermal opioid treatment was planned. The design was an open, parallel group, multicenter trial, in which 220 patients were randomized to receive either the fentanyl patch or standard opioid treatment for 30 days. The primary efficacy variable, pain intensity (PI) on a 0-10-point numerical rating scale, was recorded once daily. The primary endpoint was the relative area under the curve of PI expressed as a percentage of the maximum possible PI area under the curve. Any adverse events were recorded; four tolerability endpoints, constipation, nausea, daytime drowsiness, and sleeping disturbances, were assessed daily. Noninferiority was shown; the upper 95% confidence interval limits os the mean difference in relative PI area under the curve between the fentanyl patch and standard opioid treatment were less than 10% for both the intention-to-treat and per-protocol populations. Scores for the tolerability endpoints were similar in the treatment groups. The new fentanyl matrix patch with a lower drug load was found noninferior and as safe as established standard oral and transdermal opioid treatment.