Gabapentin and Donepezil Combination on Experimental Human Pain Models
Condition: Pain, Neuropathic
MeSH terms: Neuralgia
Study type: Interventional
Phase: Phase 1

Summary: 
      This study will compare the effects of gabapentin alone, and gabapentin + donepezil given
      together in two types of experimental electrical pain tests in up to 48 healthy male subjects
      (after 24 recruited in the first cohort an interim analysis will be performed).

      The study is a randomized, double blind, placebo controlled, 3 was cross-over design study
      with incomplete block design and 4 treatment options. Placebo, gabapentin alone (lower dose
      and higher dose) or gabapentin (lower dose) with donepezil.
    

Detailed description: 
      This study will compare the effects of gabapentin alone, and gabapentin + donepezil given
      together in two types of experimental electrical pain tests which will be conducted on the
      forearm and the lower leg, in 24 healthy male subjects initially. Gabapentin (a drug for
      treatment of seizure disorders) is one of the drugs being used for the treatment of pain
      caused by the damage to the nerves. Donepezil is a treatment to improve memory in patients
      with Alzheimer's disease. 24 more subjects may be recruited following a formal analysis
      during the trial (called interim analysis), if required for optimal scientific value. The
      study consists of 1 screening visit,1 visit to establish the baseline pain recordings before
      any treatment is given, then 3 treatment sessions, followed by a followup visit. Each
      treatment session consists of 12 days of dosing at home and 2 inpatient days for dosing and
      pain tests. Each volunteer takes part in 3 treatment sessions. In total, the study will last
      15 weeks for each volunteer. There will be 4 treatment options: placebo, higher dose of
      gabapentin, low dose of gabapentin, low dose of gabapentin + donepezil. All subjects will
      receive the last two options and one out of the first two options, in a random order selected
      by a computer before the study starts; neither the volunteers nor the persons conducting the
      pain assessments nor the study team will know which treatment the volunteers receive during
      the visits (known as a randomised, double-blind study). The study will be conducted in a
      specialist clinical research unit with adequate facilities with regard to safety and
      compliance. The results of the tests in the study will help to understand the effects of
      gabapentin and donepezil together to design future clinical trials.
    

Intervention name(s): Gabapentin lower dose; Donepezil; Placebo (Dop); Placebo (Gaba); Gabapentin higher dose
Intervention type(s): Drug; Drug; Other; Other; Drug
Intervention description(s): Repeat, oral dose; Repeat, oral dose; Placebo to donepezil, Repeat, oral dose; Placebo to gabapentin, Repeat, oral dose; Repeat, oral dose
Intervention MeSH terms: Gabapentin; Donepezil
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Basic Science
Keywords: Donepezil; allodynia; Gabapentin; Sural nerve stimulation; Electrical hyperalgesia