Conditions: Postherpetic Neuralgia Complex Regional Pain Syndromes (CRPS) Postoperative Pain
Keywords: Postherpetic Neuralgia Complex Regional Pain Syndromes (CRPS) Postoperative Pain Fentanyl Patch, transdermal Opioid analgesics
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 258
Healthy volunteers: no

Brief summary:
The purpose of this study is to evaluate the efficacy and safety of fentanyl in opioid-naive participants with post-herpetic neuralgia, complex regional pain syndrome or post-operative pain syndrome who cannot obtain a sufficient analgesic effect by the treatment of non-opioid analgesics (drug used to control pain).

Detailed description:
This is a multi-center (conducted in more than one center), double-blind (neither the participant nor the physician knows the assigned study drug), randomized (participants assigned study drug by chance), withdrawal study in opioid-naive participants with post-herpetic neuralgia (intense, typically intermittent pain along the course of a nerve caused by the varicella zoster virus), complex regional pain syndrome or post-operative pain syndrome. The study will consist of titration period (10-29 days) and double-blind period (12 weeks) and the visits will include Day 5-7, 8, 15, 22, 29 in titration period and Day 2-4, 8, 15, 22, 29, 43, 57, 71 and 85 in double-blind period. All the eligible participants will receive one-day adhesive transdermal patch (patch containing a drug that is put on the skin so the drug will enter the body through the skin) of either fentanyl at the dose ranging from 12.5 to 50 microgram/hour or matching placebo. Efficacy will be evaluated primarily by time to withdrawal due to insufficient analgesic efficacy. Participants' safety will be monitored throughout the study.

Arms:
arm 1: One-day adhesive transdermal patch (patch containing a drug that is put on the skin so the drug will enter the body through the skin) containing fentanyl (JNS020QD) applied to chest, abdomen, upper arm and thigh and replaced every day, starting at the dose of 12.5 microgram per hour (mcg/hr) for at least first 2 days, which will be increased by 12.5 mcg/hr at one time based on the medical examination of number of rescue treatments and visual analog scale (VAS) score of the participants. The dose will be increased up to maximum of 50 mcg/hr. The treatment will continue for 10-29 days and then the eligible participants from this group will be randomly assigned to either of the two groups in the double-blind period. arm 2: Participants meeting the pre-defined criteria for transfer from titration period to double-blind period and randomly assigned to fentanyl group, will be administered one-day adhesive transdermal patch containing fentanyl, applied to chest, abdomen, upper arm and thigh and replaced every day, the dose of which will be same as the final application dose in the titration period (in the range of 12.5 to 50 mcg/hr). The treatment will be continued for 12 weeks. arm 3: Participants meeting the pre-defined criteria for transfer from titration period to double-blind period and randomly assigned to placebo group, will be administered one-day adhesive transdermal placebo patch indistinguishable from fentanyl in appearance, applied to chest, abdomen, upper arm and thigh and replaced every day. The dose of fentanyl (from titration period) will be gradually decreased to prevent withdrawal symptoms and the dose of the matching placebo will be gradually increased up to same dose as the final application dose in the titration period (in the range of 12.5 to 50 mcg/hr). The treatment will continue for 12 weeks.

Interventions: intervention 1: Fentanyl intervention 2: Placebo
Intervention descriptions: intervention 1: One-day adhesive transdermal patch containing fentanyl 12.5 to 50 mcg/hr applied to chest, abdomen, upper arm and thigh and replaced every day. intervention 2: Placebo patch indistinguishable from one-day adhesive transdermal patch containing fentanyl 12.5 to 50 mcg/hr applied to chest, abdomen, upper arm and thigh and replaced every day.

Protocol document: