Amitriptyline 10% and ketamine 10% cream in neuropathic pain:

INTERVENTION: Product Name: Ketamine Product Code: 1867‐66‐9 Pharmaceutical Form: Cream INN or Proposed INN: Ketamine.HCl CAS Number: 1867‐66‐9 Other descriptive name: KETAMINE HYDROCHLORIDE Concentration unit: % percent Concentration type: equal Concentration number: 10‐ Pharmaceutical form of the placebo: Cream Route of administration of the placebo: Cutaneous use Product Name: amitriptyline Product Code: 549‐18‐8 Pharmaceutical Form: Cream INN or Proposed INN: Amitriptyline.HCL CAS Number: 549‐18‐8 Other descriptive name: AMITRIPTYLINE Concentration unit: % percent Concentration type: equal Concentration number: 10‐ Pharmaceutical form of the placebo: Cream Route of administration of the placebo: Cutaneous use CONDITION: Patients with peripheral neuropathic pain or scar pain ; MedDRA version: 17.1 Level: PT Classification code 10049002 Term: Scar pain System Organ Class: 10040785 ‐ Skin and subcutaneous tissue disorders ; MedDRA version: 17.1 Level: LLT Classification code 10029181 Term: Nerve pain System Organ Class: 100000004852 Therapeutic area: Analytical, Diagnostic and Therapeutic Techniques and Equipment [E] ‐ Anesthesia and Analgesia [E03] PRIMARY OUTCOME: Main Objective: The purpose of this study is to investigate the effect size in order to perform a power calculation for calculating a sample size for a powered RCT Primary end point(s): Difference between active and placebo cream pain score on Numeric Rating Scale Secondary Objective: none Timepoint(s) of evaluation of this end point: End of studyperiod SECONDARY OUTCOME: Secondary end point(s): Feasibility of a randomised, doubleblind, placebo‐controlled, cross‐over study with the folowing questions: effectiveness on the other ratingscales (for example the NRS, BPI sleepingscale), percentage patients responding and will be included after the testing phase; comprehensibility and completeness of questionnaires, percentage drop‐outs, side effects, logistics and randomization process, tolerance and safety of the creams ; ; Timepoint(s) of evaluation of this end point: at the end of the study INCLUSION CRITERIA: ‐ peripheral neuropatic pain (DOT: 130) ‐ =18 year, competent ‐ =5 en <10 on the numeric rating scale ‐ max. 10% total body surface ‐ in %, 1 sole: 1¾, , 1 feet: 3½, 2 feet: 7, both legs to quarter onderlegs 10, 1 hand: 3) Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18‐64 years) yes F.1.2.1 Number of subjects for this age range 40 F.1.3 Elderly (>=65 years) yes F.1.3.1 Number of subjects for this age range 40