Dosing fentanyl buccal tablet for breakthrough cancer pain: dose titration versus proportional doses

The aim of this study was to compare the efficacy and safety of doses of fentanyl buccal tablet (FBT) proportional to doses of opioids used for background analgesia versus dose titration starting with the minimal dose for the management of breakthrough cancer pain (BTcP).

A total of 82 cancer patients with BTcP who were receiving strong opioids in doses of at least 60 mg of oral morphine equivalents and having acceptable background analgesia, were selected for a multicenter unblinded study. Forty-one patients were randomized to receive FBT in doses proportional to the daily opioid doses for four consecutive episodes of BTcP (group P). Forty-one patients underwent dose titration of FBT, with an initial dose of 100 µg, for four consecutive episodes (group T). Pain intensity and symptoms associated with opioid therapy were measured before administering any dose of FBT (T0) and 15 minutes after (T15).

In all, 80 patients were considered for analysis (39 and 41 patients in group P and T, respectively). Patients were receiving a mean of 126 ± 100 mg of oral morphine equivalents (range 60-480 mg) for background analgesia. A total of 293 episodes of BTcP (144 and 149 in group P and T, respectively) were treated and considered for analysis. No differences were found in the decrease of pain intensity between the two groups. However, in patients receiving doses of oral morphine equivalents of >120 mg/day, a significant number of patients obtained a decrease in pain intensity >50% in group P in comparison with group T (p = 0.040). Also, the need for rescue medication was significantly more frequently reported in group T for the first episode of BTcP (p < 0.0005). No differences in the level of adverse effects were observed between the two groups. No differences in patients' satisfaction were reported.

According to the data obtained in this study, there is no evidence for the use of dose titration in the management of BTcP in opioid-tolerant patients. Indeed, doses proportional to basal opioid regimen for background pain seem to be effective and safe in the majority of patients. Further studies should confirm this data in patients receiving higher doses of opioids, with other rapid-onset opioids, and in other settings.