analgesic effectiveness of capsaicin 8% cutaneous patch in children

Conditions: Neuropathic Pain; Chronic Pain

Summary: this study concerns children aged to 12 to 17-years with local chronic neuropathic pain after trauma or surgery. it is a multicentric randomized controlled superiority trial in parallel arms : * experimental arm: capsaicin 8% cutaneous patch * controlled arm : hydrocolloid dressing treatment with capsaicin application is realized at baseline, and repeated 3 months after the first patch application if needed. tolerance is assessed during each application and by phone call in following days until stop of cold need. efficacy is assessed monthly by clinical consultation until the end of the study (month 4).

children aged to 12 to 17-years monitored in pediatric pain outpatient clinics in the designed investigation centers for a local chronic neuropathic pain lasting more than 2 months after trauma or surgery are proposed to participate the trial. children with persistant neuropathic pain (dn4 (diagnostic neuropathic pain) \> or = 3/7 ou dn4 \>or = 4/10) despite oral treatment following recommendations for neuropathic pain may be enrolled in the study. for children not very painful (nrs-11 (numeric rating scale) \< 7 and fdi (functional disability inventory) \< 30) and without any oral treatment for neuropathic pain, the study may be proposed as first line treatment. if both the child and his/her parents accept the trial, he/she will be included in the study. it is a multicentric randomized controlled superiority trial in parallel arms : * experimental arm: capsaicin 8% cutaneous patch * controlled arm : hydrocolloid dressing at m0, take place : baseline evaluation, agreement consent signature, inclusion and randomization, as well as first treatment application either capsaicin cutaneous patch or hydrocolloid dressing. , if needed, the treatment may be done twice with a second application three months later (m3). tolerance is assessed during each application and by phone call in following days until stop of cold need. efficacy is assessed monthly by clinical consultation until the end of the study 4 months later (m4).

Eligibility criteria:
inclusion criteria: * children aged 12 to 17 years (lower age limit of 12 has been chosen to ensure npsi full filling). * male or female. * persistent neuropathic pain more than 3 months after surgery or trauma despite treatment following recommendations. * neuropathic pain is defined as a dn4 score equal to or greater than 3/7 or 4/10, and localized in a nerve territory explained by the surgery or the trauma. * treatment, survey and follow up must be realized in an identified investigating center of the study * for patients of childbearing potential: use of an adequate method of contraception\* during the course of the study through 48 hours after the last patch application (girls of childbearing potential must have a negative serum or urine pregnancy test within 7 days prior to the first patch application). * adequate contraception includes sexual abstinence, progestogen-only oral hormonal contraception, where inhibition of ovulation is not the primary mode of action, male or female condom with or without spermicide, cap, diaphragm or sponge with spermicide, combination of male condom with either cap, diaphragm or sponge with spermicide (double barrier methods) exclusion criteria: * intellectual deficiency not allowing full filling of npsi. * insufficient command of the french language to full fill npsi and other evaluation tools. * parents' refusal of consent. * minor patients' opposition. * underlying neurological disease. * ongoing neurotoxic treatment. * already treated by capsaicin. * cutaneous lesion on pain area. * patient presenting a pain area on the face, above the hairline of the scalp, and/or in proximity to mucous membranes * hypersensitivity to the active substance or to any of the excipients listed in section 6.1 of qutenza smpc.

Keywords: neuropathic pain pediatric capsaicin randomized clinical trial