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Three presentations highlighting long-term data and improved quality of life outcomes in adults with focal onset seizures VANCOUVER, British Columbia and BOSTON, Sept. 09, 2024 (GLOBE NEWSWIRE) -- Xenon Pharmaceuticals Inc. (Nasdaq:XENE), a neuroscience-focused biopharmaceutical company dedicated to discovering, developing, and delivering life-changing therapeutics for patients in need, today announced three poster presentations at the 15th European Epilepsy Congress (EEC) taking place in Rome, Italy. Azetukalner, a novel, potent Kv7 channel opener, is the most advanced, clinically validated potassium channel modulator in late-stage development for multiple indications, including focal onset seizures (FOS), primary generalized tonic-clonic seizures (PGTCS) and major depressive disorder (MDD). “We are excited for this opportunity to engage with leading epileptologists at EEC in Rome and share long-term azetukalner data from our ongoing X-TOLE open-label extension study. Azetukalner represents the only Kv7 potassium channel opener in clinical development that is supported by Phase 2b data as well as long-term efficacy and safety data in epilepsy patients,” stated Dr. Christopher Kenney, Chief Medical Officer of Xenon. “These data are particularly impressive given the baseline disease severity, with patients who are out to 30 months in the open-label extension study showing a greater than 90% reduction in median monthly seizure frequency, while approximately one in four patients on azetukalner for at least two years in the OLE have experienced a period of seizure freedom of a year or longer.” Dr. Kenney continued, “We are also presenting patient-reported survey data illustrating the substantial burden of illness for people living with epilepsy, with reduced quality of life, high seizure frequency and fatigue, as well as other comorbidities such as anxiety and depression, further underscoring the need for new medications to help people living with epilepsy.” Presentations at EEC: Poster #P282: Azetukalner (XEN1101), a Novel, Potent Kv7 Potassium Channel Opener: Interim Data From an Ongoing, Long‑Term, Open‑Label Extension of a Phase 2b Study (X‑TOLE) in Adults With Focal Onset SeizuresPresenter: Jacqueline A. French, New York University Grossman School of Medicine and NYU Langone Health, New York, NYSession Times: Daily from 1:30-3:00 pm CEST Poster #P281: Long-term, Quality of Life in Epilepsy Inventory-31 (QOLIE-31) Improvements in Adults With Focal Onset Seizures Treated With Azetukalner (XEN1101) in an Ongoing, Open-Label Extension of a Phase 2b study (X-TOLE)Presenter: Christian Brandt, Bethel Epilepsy Centre, Mara Hospital, University Hospital for Epileptology, Bielefeld, GermanySession Times: Daily from 1:30-3:00 pm CESTPoster Tour: S2 Clinical Neurophysiology/Drug Therapy Poster #P406: Non-seizure Symptoms, Mental Health Comorbidities, and Quality of Life in Patients Reporting Focal Onset SeizuresPresenter: Cynthia Harden, Xenon Pharmaceuticals Inc. Session Times: Daily from 1:30-3:00 pm CEST Posters will be available for viewing at the conference from Sunday, September 8 until Tuesday, September 10 at 4:00 pm CEST and will be added to the Xenon website consistent with conference guidelines. Xenon is also hosting a Scientific Exhibit at location SE1 and Booth #346. About Xenon Pharmaceuticals Inc.Xenon Pharmaceuticals (Nasdaq:XENE) is a neuroscience-focused biopharmaceutical company committed to discovering, developing, and commercializing innovative therapeutics to improve the lives of people living with neurological and psychiatric disorders. We are advancing a novel product pipeline to address areas of high unmet medical need, including epilepsy and depression. Azetukalner, our lead Kv7 channel opener, represents the most advanced, clinically validated potassium channel modulator in late-stage clinical development for multiple indications. For more information, please visit www.xenon-pharma.com. About the Azetukalner Phase 3 Epilepsy ProgramXenon’s Phase 3 epilepsy program includes three ongoing Phase 3 clinical trials in focal onset seizures (FOS) and primary generalized tonic-clonic seizures (PGTCS). Designed closely after the Phase 2b X-TOLE clinical trial, the Phase 3 X-TOLE clinical trials are multicenter, randomized, double-blind, placebo-controlled studies evaluating the clinical efficacy, safety, and tolerability of 15 mg or 25 mg of azetukalner administered with food as adjunctive treatment in approximately 360 patients with FOS per study. The primary efficacy endpoint is the median percent change (MPC) in monthly seizure frequency from baseline through the double-blind period (DBP) of azetukalner compared to placebo. X-ACKT is a multicenter, randomized, double-blind, placebo-controlled study evaluating the clinical efficacy, safety, and tolerability of 25 mg of azetukalner administered with food as adjunctive treatment in approximately 160 patients with PGTCS. The primary efficacy endpoint is the MPC in monthly PGTCS frequency from baseline through the DBP of azetukalner compared to placebo. Safe Harbor StatementThis press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, and the Private Securities Litigation Reform Act of 1995 and Canadian securities laws. These forward-looking statements are not based on historical fact, and include statements regarding the timing of and potential results from clinical trials; the potential efficacy, safety profile, future development plans in current and anticipated indications, addressable market, regulatory success and commercial potential of our and our partners’ product candidates; the efficacy of our clinical trial designs; our ability to successfully develop and achieve milestones in our azetukalner and other pipeline and development programs; and our ability to successfully develop and obtain regulatory approval of azetukalner and our other product candidates. These forward-looking statements are based on current assumptions that involve risks, uncertainties and other factors that may cause the actual results, events, or developments to be materially different from those expressed or implied by such forward-looking statements. These risks and uncertainties, many of which are beyond our control, include, but are not limited to: clinical trials may not demonstrate safety and efficacy of any of our or our collaborators’ product candidates; promising results from pre-clinical development activities or early clinical trial results may not be replicated in later clinical trials; our assumptions regarding our planned expenditures and sufficiency of our cash to fund operations may be incorrect; our ongoing discovery and pre-clinical efforts may not yield additional product candidates; any of our or our collaborators’ product candidates, including azetukalner, may fail in development, may not receive required regulatory approvals, or may be delayed to a point where they are not commercially viable; we may not achieve additional milestones in our proprietary or partnered programs; regulatory agencies may impose additional requirements or delay the initiation of clinical trials; the impact of market, industry, and regulatory conditions on clinical trial enrollment; the impact of competition; the impact of expanded product development and clinical activities on operating expenses; the impact of new or changing laws and regulations; as well as the other risks identified in our filings with the U.S. Securities and Exchange Commission and the securities commissions in British Columbia, Alberta, and Ontario. These forward-looking statements speak only as of the date hereof and we assume no obligation to update these forward-looking statements, and readers are cautioned not to place undue reliance on such forward-looking statements. “Xenon” and the Xenon logo are registered trademarks or trademarks of Xenon Pharmaceuticals Inc. in various jurisdictions. All other trademarks belong to their respective owner. Contacts: For Investors:Chad FugereVice President, Investor Relations(857) 675-7275investors@xenon-pharma.com For Media:Colleen AlabisoSenior Vice President, Corporate Affairs(617) 671-9238media@xenon-pharma.com

Raised Gross Proceeds of Approximately $100 Million in a Private Placement with Leading Institutional Healthcare Investors Continuing to Enroll Patients in Phase 3 LEVEL Study with 39 Investigative Sites Initiated In April, Hosted the KOL Event, “LEVEL Setting,” Featuring Four Experts in Heart Failure Discussing the Unmet Medical Need in PH-HFpEF and Potential of Levosimendan to Address Disease CHAPEL HILL, N.C., Aug. 13, 2024 (GLOBE NEWSWIRE) -- Tenax Therapeutics, Inc. (“Tenax”) (Nasdaq: TENX), a Phase 3, development-stage pharmaceutical company focused on developing and commercializing products that address cardiovascular and pulmonary diseases with high unmet medical need, announced financial results for the second quarter of 2024 and provided a corporate update. “In the second quarter, Tenax has undergone a significant transformation made possible by successful execution across our strategic priorities,” said Chris Giordano, President and Chief Executive Officer of Tenax. “Several patients randomized in our Phase 3 LEVEL trial in Q1 and early Q2 have now completed 12 weeks of therapy and all have continued into the open label extension. We secured important U.S. intellectual property, and attained the global development and commercial rights to levosimendan for the treatment of PH-HFpEF.” “We also conducted the KOL Event, “LEVEL Setting”, in April, which featured a panel of globally renowned cardiologists who reviewed the significant unmet medical need in PH-HFpEF and the potential of levosimendan to address this debilitating condition. Finally, we raised gross proceeds of approximately $100 million in a private placement financing, providing Tenax the resources to further advance the levosimendan Phase 3 program, with the ultimate goal of bringing to market the first FDA-approved treatment for the millions of patients who suffer from PH-HFpEF.” Recent Corporate and Clinical Highlights In August 2024, Tenax announced the closing of a private placement financing that resulted in total gross proceeds to the Company of approximately $100 million, before deducting placement agent fees and other estimated offering expenses.In April 2024, Tenax announced that the United States Patent and Trademark Office (USPTO) granted the Company a patent, U.S. Patent No. 11,969,424, covering the use of TNX-103 (oral levosimendan), TNX-102 (subcutaneous levosimendan), TNX-101 (IV levosimendan), the active metabolites of levosimendan (OR1896 and OR18955) and various combinations of cardiovascular drugs with levosimendan when used to improve exercise performance in patients with pulmonary hypertension from heart failure with preserved ejection fraction (PH-HFpEF). The ‘424 patent expressly provides IP protection for levosimendan at all therapeutic doses.In April 2024, Tenax hosted “LEVEL Setting” – a scientific roundtable exploring the rationale for TNX-103 (oral levosimendan) in the treatment of PH-HFpEF. Presentations were made by four globally recognized experts in the field who then answered questions from attendees (LINK TO EVENT): Understanding the setting of PH-HFpEF – Sanjiv Shah, M.D. (Northwestern University)Mechanism of Action of Levosimendan – Daniel Burkhoff, M.D., Ph.D. (Cardiovascular Research Foundation and Columbia University)Review of data from the Phase 2 HELP Study – Barry Borlaug, M.D. (Mayo Clinic)Current treatment landscape in PH-HFpEF – Javed Butler, M.D., M.P.H., M.B.A. (Baylor Scott & White) Second Quarter 2024 Financial Results Tenax reported cash and cash equivalents of $9.4 million as of June 30, 2024, versus $9.8 million as of December 31, 2023. Following the close of the reporting period, the Company raised gross proceeds of approximately $100 million in a private placement financing, which closed on August 8, 2024, with leading institutional healthcare investors. Research and Development expenses for the second quarter of 2024 were $2.3 million, compared to $0.2 million for the second quarter of 2023. The $2.1 million increase year-over-year is primarily attributable to increased costs for the ongoing Phase 3 LEVEL study. General and administrative expenses for the second quarter of 2024 were $1.3 million versus $1.0 million for the second quarter of 2023. Tenax reported a net loss of $3.6 million or $1.83 per share for the second quarter of 2024, compared to a net loss of $1.1 million or $4.00 per share for the second quarter of 2023. About Levosimendan (TNX-101, TNX-102, TNX-103) Levosimendan is a unique, potassium ATP channel activator and calcium sensitizer that affects the heart and vascular system through multiple mechanisms of action. Initially discovered and developed by Orion Corporation in Finland, intravenous levosimendan has been granted marketing authorization in 60 countries outside the United States for use in hospitalized patients with acutely decompensated heart failure. Results of Tenax’s Phase 2 HELP study of levosimendan in patients with pulmonary hypertension (PH) with heart failure with preserved ejection fraction (HFpEF) demonstrated that IV levosimendan produces potent dilation of the central and pulmonary venous circulations which translates into an improvement in exercise capacity, a discovery that is the basis of LEVEL, the Phase 3 investigation of Tenax’s potential groundbreaking therapy. To date, no other drug therapy has improved exercise tolerance in patients with PH associated with HFpEF, “a growing epidemic with high morbidity and mortality and no treatment. The clear unmet need and lethal nature of PH-HFpEF must be met with novel solutions at all levels of therapeutic development” (AHA Scientific Advisory, “A Call to Action,” 2022). About Tenax Therapeutics Tenax Therapeutics, Inc. is a Phase 3, development-stage pharmaceutical company focused on developing and commercializing products that address cardiovascular and pulmonary diseases with high unmet medical need. Tenax owns global rights to develop and commercialize levosimendan, which it has prioritized in the near term. Tenax also may resume developing its unique oral formulation of imatinib. For more information, visit www.tenaxthera.com. Tenax’s common stock is listed on The Nasdaq Stock Market LLC under the symbol “TENX”. Caution Regarding Forward-Looking Statements Except for historical information, all of the statements, expectations and assumptions contained in this press release are forward-looking statements. These forward-looking statements may include information concerning possible or projected future business operations. Actual results might differ materially from those explicit or implicit in the forward-looking statements. Important factors that could cause actual results to differ materially include: the expected use of proceeds from our recent private placement; the expected cash runway with the net proceeds of our recent private placement, and risks associated with our cash needs; risks related to our business strategy, including the prioritization and development of product candidates; risks of our clinical trials, including, but not limited to, the timing, delays, costs, design, initiation, enrollment, and results of such trials; any delays in regulatory review and approval of product candidates in development; reliance on third parties, including Orion Corporation, our manufacturers and CROs; risks regarding the formulation, production, marketing, customer acceptance and clinical utility of our product candidates; our estimates regarding the potential market opportunity for our product candidates; the potential advantages of our product candidates; our competitive position; intellectual property risks; risks related to our continued listing on Nasdaq; our ability to maintain our culture and recruit, integrate and retain qualified personnel and advisors, including on our Board of Directors; volatility and uncertainty in the global economy and financial markets in light of the possibility of pandemics, global financial and geopolitical uncertainties, including in the Middle East and the Russian invasion of and war against the country of Ukraine; changes in legal, regulatory and legislative environments in the markets in which we operate and the impact of these changes on our ability to obtain regulatory approval for our products; and other risks and uncertainties set forth from time to time in our SEC filings. Tenax assumes no obligation and does not intend to update these forward-looking statements except as required by law. Contacts Investor Contact:John FrauncesManaging DirectorLifeSci Advisors, LLCC: 917-355-2395jfraunces@lifesciadvisors.com or Brian MullenLifeSci Advisors, LLCC: 203-461-1175bmullen@lifesciadvisors.com Tenax Therapeutics, Inc. - Consolidated Balance Sheet for the Periods Ended June 30, 2024 and December 31, 2023 June 30, 2024 December 31, 2023 (Unaudited) ASSETS Current assets Cash and cash equivalents$9,384,015 $9,792,130 Prepaid expenses 1,181,527 1,639,797 Other current assets 50,250 251,583 Total current assets 10,615,792 11,683,510 Other assets 1,117 1,117 Total assets$10,616,909 $11,684,627 LIABILITIES AND STOCKHOLDERS’ EQUITY Current liabilities Accounts payable$869,656 $2,073,149 Accrued liabilities 592,379 1,012,468 Note Payable 278,802 500,903 Total current liabilities 1,740,837 3,586,520 Total liabilities 1,740,837 3,586,520 Commitments and contingencies; Stockholders' equity Preferred stock, undesignated, authorized 4,818,654 shares; Series A Preferred stock, par value $0.0001, authorized 5,181,346 shares; issued and outstanding 210, as of June 30, 2024 and December 31, 2023, respectively - - Common stock, par value $0.0001 per share; authorized 400,000,000 shares; issued and outstanding 1,958,245 as of June 30, 2024 and 298,281 as of December 31, 2023, respectively 196 30 Additional paid-in capital 313,503,142 305,350,830 Accumulated deficit (304,627,266) (297,252,753)Total stockholders’ equity 8,876,072 8,098,107 Total liabilities and stockholders' equity$10,616,909 $11,684,627 Tenax Therapeutics, Inc. - Consolidated Income Statement for the Periods Ended June 30, 2024 and June 30, 2023 Three months ended June 30, Six months ended June 30, 2024 2023 2024 2023 Operating expenses General and administrative $1,344,389 $1,038,257 $2,577,063 $2,311,987 Research and development 2,327,632 197,903 5,003,284 463,637 Total operating expenses 3,672,021 1,236,160 7,580,347 2,775,624 Net operating loss 3,672,021 1,236,160 7,580,347 2,775,624 Interest expense 9,189 9,126 17,153 16,476 Interest income (104,883) (139,859) (222,333) (216,136)Other expense (income), net (654) 911 (654) (62,866)Net loss $ 3,575,673 $ 1,106,338 $ 7,374,513 $ 2,513,098 Net loss per share, basic and diluted $(1.83) $(4.00) $(4.65) $(12.77)Weighted average number of common shares outstanding, basic and diluted 1,958,245 276,454 1,586,650 196,799