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H XENON Xenon Pharmaceuticals Reports Third Quarter 2021 Financial Results and Provides Corporate Update November 10 , 2021 XEN1101 X - TOLE Presentations Scheduled at AES 2021 with Planning Underway for Phase 3 Initiation in 2022 Conference Call at 4:30 pm ET Today -- Xenon Pharmaceuticals Inc. BURNABY , British Columbia , Nov. 10 , 2021 ( GLOBE NEWSWIRE ) ( Nasdaq : XENE ) , a neurology - focused biopharmaceutical company , today reported financial results for the third quarter ended September 30 , 2021 and provided a corporate update . Mr. Ian Mortimer , Xenon's President and Chief Executive Officer stated , " We were incredibly excited last month to announce positive topline results from our Phase 2b X - TOLE clinical trial , which demonstrated impressive efficacy for XEN1101 in ' difficult - to - treat ' adult patients with focal epilepsy . With its differentiated potassium channel mechanism of action , strong efficacy data , and ' ease - of - use ' attributes , including once - a - day dosing in the evening with no titration , we believe XEN1101 could play an important role in treating focal epilepsy . We look forward to presenting additional X - TOLE data in a late - breaking poster at the upcoming AES 2021 meeting , where we are also sponsoring a scientific symposium featuring a panel discussion with key opinion leaders in the adult focal epilepsy space . " Mr. Mortimer added , “ Based on the positive outcome of the X - TOLE clinical trial , our efforts are focused on finalizing the clinical development plan for XEN1101 , including a planned end - of - Phase 2 meeting with FDA anticipated in the second quarter of 2022 to be followed by the initiation of our Phase 3 program in adult focal epilepsy anticipated in the second half of 2022. Supported by the strength of the topline X - TOLE data , we are actively evaluating other potential epilepsy indications for XEN1101 . In addition , an investigator - led study evaluating XEN1101 as a treatment for major depressive disorder is now underway , and we also plan to initiate a company - sponsored MDD study in the first half of 2022. In parallel to our XEN1101 - related activities , patient enrollment continues in our Phase 3 ' EPIK ' pediatric clinical trial evaluating XEN496 as a treatment of KCNQ2 developmental and epileptic encephalopathy . New sites and jurisdictions continue to come online to support the EPIK study , which is expected to be completed in the first half of 2023. " Highlights and Anticipated Milestones Proprietary Programs