Transdermal opioids for cancer pain control in patients with renal impairment

Objectives: As guidelines for opioid use in renal-impaired patients with cancer are limited, the authors sought to assess the efficacy, safety, and tolerability, of transdermal buprenorphine for moderate/severe cancer pain in renal-impaired outpatients. Methods: In a prospective parallel-group active-controlled study, n = 42 consecutively recruited outpatients with or without renal impairment (serum creatinine >=1.3 or <=1.2 mg/dL, respectively) were treated with transdermal buprenorphine (group BUP) or fentanyl (group FEN), respectively. Patients were followed up, at home, by the nonprofit ANT-Italia-foundation physicians in Bologna, Italy. Measurements at 10 (T1), 30 (T2), and 90 (T3) days after enrollment (T0) were pain intensity (Numerical Rating Scale [NRS]), Karnofski score, opioid dose (µg/h), rescue-dose consumption, and occurrence of adverse effects. Patients recorded subjective measurements in a personal diary. Upon data analysis, investigators were blinded to the patient group. Results: At T0, in groups BUP and FEN, median NRS score was 8.0 (CI, 7.4-8.4); its reduction over time (T3; NRS = 3.0; CI, 2.1-3.8 and 2.0-4.0, respectively) was significant and constant in both groups (t-test; T0-T1, T1-T2, and T2-T3; p < 0.0001, p < 0.001, and p < 0.05, respectively). At all times, there were no significant differences in pain scores between the groups. In all evaluations, adverse effects were reported n = 73/126 times (60.8 percent) and showed no significant association (2, p > 0.05) with the study groups. Conclusions: Transdermal buprenorphine, in outpatients with cancer and renal impairment, is as effective, safe, and tolerable as fentanyl in patients without such impairment. These results add further evidence to the notion that buprenorphine, with its peculiar pharmacokinetics, may be an appropriate choice for opioid treatment in patients with renal impairment.