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H XENON Xenon Pharmaceuticals Announces Positive Topline Results from Phase 2b ' X - TOLE ' Clinical Trial of XEN1101 for the Treatment of Focal Epilepsy October 4 , 2021 All Primary and Secondary Seizure Reduction Endpoints Statistically Significant Across All Dose Groups , with p - value of < 0.001 for 20 mg and 25 mg Dose Groups Xenon to Host Conference Call and Live Webcast Today at 7:30 am Eastern Time BURNABY , British Columbia , Oct. 04 , 2021 ( GLOBE NEWSWIRE ) Xenon Pharmaceuticals Inc. ( Nasdaq : XENE ) , a neurology - focused biopharmaceutical company , today reported positive topline results from the Phase 2b X - TOLE clinical trial , which evaluated the clinical efficacy , safety , and tolerability of XEN1101 a differentiated Kv7 potassium channel modulator administered as adjunctive treatment in adult patients with focal epilepsy . - - The trial met its primary efficacy endpoint with XEN1101 demonstrating a statistically significant and dose - dependent reduction from baseline in monthly ( defined as 28 days ) focal seizure frequency when compared to placebo ( monotonic dose response ; p < 0.001 ) . Additional primary and secondary measures included a pairwise comparison of each active dose to placebo and a responder analysis with the proportion of patients who achieved a 50 % or greater reduction in monthly focal seizure frequency from baseline . These results are shown in the following table ; all p - values are 2 - sided comparing the active dose to placebo : XEN1101 25 mgXEN1101 20 mgXEN1101 10mg Placebo | ( N = 112 ) Median Reduction from Baseline 52.8 % ( N = 51 ) 46.4 % | ( N = 46 ) 33.2 % | ( N = 114 ) 18.2 % in Monthly Focal Seizure ( p < 0.001 ) ( p < 0.001 ) ( p = 0.035 ) Frequency Patients with at least a 50 % Reduction in Monthly Focal 54.5 % ( p < 0.001 ) 43.1 % ( p < 0.001 ) 28.3 % | ( p = 0.037 ) 14.9 % Seizure Frequency from Baseline Jacqueline A. French , MD , Professor in the Department of Neurology at NYU Langone Health and Co- director of Epilepsy Clinical Trials at NYU Langone's Comprehensive Epilepsy Center ; Founder / Director of the Epilepsy Study Consortium ; and Chair of the XEN1101 X - TOLE Steering Committee , stated , " Many patients today are living with the debilitating impacts of focal seizures , even while taking multiple anti - seizure medications , so there is a substantial need for new , efficacious and well - tolerated