Efficacy and Safety of Fentanyl Citrate Patch, Including a Low-Dose 0.5 mg Formulation, in Opioid-Naïve Patients with Cancer Pain

Comparison of Analgesic Efficacy and Safety of Low-Dose Transdermal Fentanyl and Oral Oxycodone in Opioid-Naïve Patients with Cancer Pain

In Japan, a low-dose transdermal fentanyl (TDF; 0.5 mg) has been approved to address pain in opioid-naïve patients with cancer; however, efficacy and safety data are lacking. To determine the efficacy and safety of TDF, patients with opioid-naïve cancer pain prescribed TDF (0.5 mg/d) and oral oxycodone sustained-release formulation (OXY) 10 mg/d were extracted from electronic medical and nursing records. Overall, 40 and 101 subjects were analyzed in the TDF and OXY groups, respectively. Compared with baseline (median [minimum, maximum]) values, changes in the Numerical Rating Scale (NRS) score on days 1, 3, and 7 post-administration were as follows: TDF (0 [-5, 4]) and OXY (-1.0 [-8, 3]); TDF (-1.5 [-6, 3]) and OXY (-2.0 [-8, 4]); and TDF (-2.0[-6, 3]) and OXY (-3.0[-8, 5]), respectively. No significant difference was observed between the groups on days 1 and 3; however, the change in the NRS on day 7 was significantly higher in the OXY group than that in the TDF group. Regarding adverse events, nausea occurred in 12.5 and 13.9% of patients in the TDF and OXY groups, respectively, while 12.5% of TDF- and 10.9% of OXY-treated patients experienced somnolence, revealing similar occurrence in both groups. However, constipation was more common in the OXY group (TDF: 50.0%, OXY: 71.3%). No serious adverse events (e.g., respiratory depression) were observed in either group. Low-dose TDF (0.5 mg), available only in Japan, showed comparable efficacy and safety to OXY (10 mg/d) and can be a first choice for opioid-naïve patients with cancer pain.

Optimal opioid treatment requires a consensual approach

This phase III multicenter randomized double-blind placebo-controlled comparative study evaluated the efficacy and safety of diclofenac sodium patches for the treatment of cancer pain. The study consisted of a 2-week to 4-week open-label dose-titration phase and a 4-week double-blind phase. In the double-blind phase, patients who were expected to continue treatment of cancer pain with nonopioid analgesics alone were randomized to the diclofenac sodium patch or placebo group. Once-daily diclofenac sodium patches were started at 150 mg/day (2 patches) and could be increased up to 225 mg/day (3 patches). The primary efficacy endpoint was the time to insufficient analgesic response. Statistical analysis of the double-blind phase included data from 120 patients of the diclofenac sodium patch group and 118 patients of the placebo group. Time to insufficient analgesic response was significantly longer with diclofenac sodium patches than with placebo (P = 0.0016). The hazard ratio for insufficient response for diclofenac sodium patch vs placebo was 0.459 (95% confidence interval, 0.275-0.768). Regarding sleep quality during the double-blind phase, the proportion of patients with “very good sleep” or “good sleep” in the diclofenac sodium patch and placebo groups was 90.8% and 88.1% at the start of the double-blind phase and 81.4% and 78.6% at the final assessment, respectively. The incidence of adverse events was 60.8% (73/120) in the diclofenac sodium patch group and 60.2% (71/118) in the placebo group. Once-daily diclofenac sodium patches are effective in treating cancer pain and are well tolerated.

An Open-Label Study of the Pharmacokinetics and Tolerability of Once-a-Day Fentanyl Citrate Patch in Japanese Pediatric and Adolescent Patients with Cancer Pain

BACKGROUND

Transdermal fentanyl is not yet approved for pediatric and adolescent use in Japan.

OBJECTIVE

Serum fentanyl concentration and the safety and efficacy of once-a-day fentanyl citrate patch were investigated in pediatric and adolescent patients with cancer pain.

METHODS

In this open-label, uncontrolled study, cancer patients aged 2-19 years being treated with strong opioid analgesics were switched to fentanyl citrate patch for 2 weeks. Serum fentanyl concentration was measured at steady state, and severity of pain was evaluated.

RESULTS

Eleven patients (four patients aged 2-5 years and seven patients aged 6-19 years) were enrolled. No patient received a dose exceeding 2 mg. Mean serum fentanyl concentrations after administration of 0.5 mg, 1 mg, and 2 mg were 144 pg/mL (n = 4), 277 pg/mL (n = 3), and 2070 pg/mL (n = 4), respectively. All patients were included in the efficacy and safety analysis, but one patient was excluded from the pharmacokinetic analysis because blood was sampled on the day after blood transfusion. A subgroup analysis showed that the mean serum fentanyl concentration tended to be higher in pre-school patients (aged 2-5 years) than in school-aged and adolescent patients (aged 6-19 years) and than in reports of adult patients (aged 20 years and above) who received the same dose. No respiratory adverse events were observed, and pain was well controlled.

CONCLUSION

Fentanyl citrate patch tended to result in a higher serum fentanyl concentration in pre-school patients than in school-aged, adolescent, and adult patients who received the same dose. The patch provided adequate pain control, was well tolerated, and did not cause respiratory adverse events.

TRIAL REGISTRATION NUMBER

JPRN-JapicCTI-183909.

A multicenter, randomized, double-blind, placebo-controlled, comparative study to evaluate the efficacy and safety of newly developed diclofenac patches in patients with cancer pain

ABSTRACT

This phase III multicenter randomized double-blind placebo-controlled comparative study evaluated the efficacy and safety of diclofenac sodium patches for the treatment of cancer pain. The study consisted of a 2-week to 4-week open-label dose-titration phase and a 4-week double-blind phase. In the double-blind phase, patients who were expected to continue treatment of cancer pain with nonopioid analgesics alone were randomized to the diclofenac sodium patch or placebo group. Once-daily diclofenac sodium patches were started at 150 mg/day (2 patches) and could be increased up to 225 mg/day (3 patches). The primary efficacy endpoint was the time to insufficient analgesic response. Statistical analysis of the double-blind phase included data from 120 patients of the diclofenac sodium patch group and 118 patients of the placebo group. Time to insufficient analgesic response was significantly longer with diclofenac sodium patches than with placebo (P = 0.0016). The hazard ratio for insufficient response for diclofenac sodium patch vs placebo was 0.459 (95% confidence interval, 0.275-0.768). Regarding sleep quality during the double-blind phase, the proportion of patients with "very good sleep" or "good sleep" in the diclofenac sodium patch and placebo groups was 90.8% and 88.1% at the start of the double-blind phase and 81.4% and 78.6% at the final assessment, respectively. The incidence of adverse events was 60.8% (73/120) in the diclofenac sodium patch group and 60.2% (71/118) in the placebo group. Once-daily diclofenac sodium patches are effective in treating cancer pain and are well tolerated.