Dose Ranging Study of the Efficacy and Tolerability of Tonabersat in the Prophylaxis of Migraine Headache
Condition: Migraine Without Aura; Migraine With Aura
MeSH terms: Migraine Disorders; Migraine without Aura; Migraine with Aura; Headache
Study type: Interventional
Phase: Phase 2

Summary: 
      Primary objective:

      To investigate the efficacy and tolerability of two doses of tonabersat compared to placebo
      in the prophylaxis of migraine headache and to evaluate the longer term tolerability of
      tonabersat in an open label extension.

      Secondary objective(s):

      To obtain further data on the efficacy and dose response of tonabersat; To extend the safety
      and tolerability database of tonabersat; To obtain data on the pharmacokinetics of
      tonabersat.
    

Detailed description: 
      A multi-centre, double-blind, placebo controlled, randomized, parallel group, dose ranging
      study to investigate the efficacy and tolerability of two different target doses of
      tonabersat and placebo in the prophylaxis of migraine. Following initial screening patients
      will enter a 4 week baseline assessment period, prior to randomization to one of three
      treatment groups. Subsequently patients will be allocated, according to the predetermined
      randomization schedule, to treatment with placebo or a target dose of tonabersat 40 mg/day or
      80 mg/day in a 20 week treatment period. A dose titration regimen will be employed over a
      period of 4 weeks and treatment will then be maintained for a further 16 weeks. During the
      baseline assessment period and the treatment period patients will maintain a daily record
      (diary data) of the occurrence of migraine headache, the severity of an attack, the
      presence/absence of a preceding aura, other symptoms associated with the migraine and details
      of the use of rescue medication (patients will be permitted to use their usual
      symptomatic/acute treatment as rescue medication throughout the trial). Patients will attend
      the clinic for assessment and collection of blood and urine samples for laboratory analysis,
      and a sub-population of patients will participate in a pharmacokinetic study. A total of 7
      visits are planned during the randomized double-blind treatment period.

      On completion of the randomized double-blind treatment period all patients will be offered
      the opportunity to enter an open label extension study where all patients receive tonabersat.
      A dose titration regimen will be employed over a period of 1 month and the final assigned
      dose of tonabersat (40, 60 or 80 mg/day) will be continued for the next 12 months. During the
      open label extension patients will attend the clinic for regular assessment of migraine
      status and safety. A total of 5 visits are planned.
    

Intervention name(s): Tonabersat; Tonabersat; Placebo
Intervention type(s): Drug; Drug; Drug
Intervention description(s): Tablets, 4 week dose titration and 16 weeks treatment at target dose of 40 mg per day; Tablets: 4 week titration and 16 weeks at target dose of 80 mg per day; Tablets; 4 week dose titration with 16 weeks at target dose
Other intervention name(s): SB220453; SB220453
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Prevention