• Video-recorded EEG was primary efficacy measure. Baseline vEEG and the vEEG at Visit 4 (Days 19 to 20; end point DB treatment phase or early withdrawal) will be read by a blinded central reader [ Time Frame: Video-recorded EEG was primary efficacy measure. Baseline vEEG and the vEEG at Visit 4 (Days 19 to 20; end point DB treatment phase or early withdrawal) will be read by a blinded central reader ] [ Designated as safety issue: No ]
  

• Percent treatment responders >=50% reduction seizure rate. ·Percentage change in seizure rate recorded on subject take-home records. Percentage change in seizure rates for all seizure types recorded on VEEG. [ Time Frame: Baseline to endpoint of double blind phase ] [ Designated as safety issue: No ]
  

This is a world wide, multicenter, randomized, double-blind, placebo-controlled study to evaluate the tolerability, safety and efficacy of 3 target doses (5, 15, and 25 mg/kg/day) of topiramate compared with placebo as an adjunct therapy in infants with refractory partial onset seizures (POS). There are 4 phases to the study, a screening phase of 3 days, a double blind treatment phase of 20 days, a one year open label extension phase and a post-treatment (taper and withdrawal) phase. The oral liquid formulation will also be assessed during this study, as it is investigational, unlike the marketed sprinkle formulation.

5, 15, 25 mg/kg/day of topriramate sprinkle and oral liquid formulation will be administered during the four phases of the study.