Is there a ceiling effect of transdermal buprenorphine? Preliminary data in cancer patients.

OBJECTIVE: The aim of this preliminary study was to explore the possibility of using higher doses of transdermal buprenorphine (TD-BUP) than those commonly used and available as manufactured patches, which are based on the assumption that BUP may have a ceiling effect that has never been determined yet.

MATERIALS AND METHODS: Ten patients who were already receiving TD-BUP (70 microg/h, which is about 1.6 mg/day) and were no longer responsive to this dosage were administered higher doses up to a maximum of 140 microg/h within 6 days, when the study was completed.

RESULTS: In six patients, dose increments of TD-BUP were effective, and patients achieved adequate analgesia within 6 days. Four patients discontinued the treatment due to inefficacy of TD-BUP 140 microg/h and were switched to other opioids until achieving stabilization (oxycodone 320 and 400 mg/day, methadone 120 mg/day, transdermal fentanyl 200 microg/h). This group of patients required higher doses than those chosen for TD-BUP, underlying the need to escalate the dose rapidly, a modality not accomplished with transdermal drugs. Adverse effects did not change and were similar to those observed before increasing the dose of TD-BUP. On the basis of these preliminary data, patients requiring doses higher than 70 microg/h of TD-BUP, in the range of 105-140 microg/h, may still have an analgesic benefit without important consequences in terms of adverse effects. It cannot be excluded that even higher doses may be effective, as some patients required rapid titration with higher morphine equivalent doses, and according to the protocol, other opioids were provided to facilitate this process. Further studies should clarify the role and the benefit of TD-BUP in specific clinical circumstances.