Crystalys Therapeutics Strengthens Board of Directors and Leadership Team as Dotinurad Advances Through Global Phase 3 Development

Tim Walbert, former Chairman, President and CEO of Horizon Therapeutics, is named Chairman of the Board

Seth H.Z. Fischer, former Chief Executive Officer of Vivus and longtime Johnson & Johnson executive, is appointed to the Board of Directors on behalf of Catalys Pacific

DeAnne Reid has been appointed as Chief Administrative Officer

SAN DIEGO, Sept. 23, 2026 /PRNewswire/ -- Crystalys Therapeutics Inc. ('Crystalys' or 'the Company'), a clinical-stage biopharmaceutical company focused on addressing the significant unmet medical needs of patients living with gout, today announced a series of leadership appointments that further strengthen the Company as it advances dotinurad through its registrational program.

Tim Walbert, former Chairman, President and CEO of Horizon Therapeutics, has been named Chairman of Crystalys' Board of Directors after serving as an Independent Director since January 2026. Seth H.Z. Fischer, former Chief Executive Officer of Vivus and a veteran Johnson & Johnson executive, has joined the Board of Directors representing Catalys Pacific. Crystalys has also promoted DeAnne Reid to Chief Administrative Officer, expanding the Company's executive leadership team as it continues to scale its operations.

In connection with the board appointments, Co-Founder BT Slingsby, M.D., Ph.D., M.P.H., who has served as Executive Chairman since the Company's founding, will transition to a Board Observer role on behalf of Catalys Pacific.

"We are building Crystalys for the next stage of our growth, and Tim, Seth and DeAnne bring the leadership and experience that will support dotinurad as it advances through our registrational program," said James M. Mackay, Ph.D., Co-Founder, Chief Executive Officer and President of Crystalys Therapeutics. "Tim has an exceptional track record of building and leading successful biopharmaceutical companies, including bringing important new therapies to people living with gout. Seth brings decades of operating and commercial experience across the pharmaceutical industry, and DeAnne will continue to play a critical role in building the organizational infrastructure to support our anticipated growth. Together, they significantly strengthen our ability to execute on our goal of establishing dotinurad as an important new treatment option for people living with gout. BT's vision and leadership have been instrumental in taking Crystalys from its founding to the global late-stage company it is today," added Dr. Mackay. "We are grateful for his contributions as Chairman and pleased that we will continue to benefit from his perspective and counsel."

Mr. Walbert led Horizon Therapeutics as Chairman, President and Chief Executive Officer from 2008 to 2023, transforming the company into a leading rare-disease biopharmaceutical organization and ultimately guiding its acquisition by Amgen for approximately $28 billion. Earlier in his career, he served as President, Chief Executive Officer and a member of the Board of Directors of IDM Pharma Inc. and held senior commercial leadership positions at NeoPharm and Abbott, now AbbVie, where he led the global development and launch of HUMIRA across multiple indications. He has also previously served on the boards of leading industry organizations, including the Biotechnology Innovation Organization (BIO) and the Pharmaceutical Research and Manufacturers of America (PhRMA). Mr. Walbert has served as an Independent Director of Crystalys since January 2026.

"I am honored to take on this role at such an important moment for Crystalys," said Mr. Walbert. "Gout is the most common form of inflammatory arthritis, yet a significant treatment gap remains for patients who are not adequately controlled on or cannot tolerate first-line therapy. I believe dotinurad has the potential to close that gap, and Crystalys has assembled the clinical program, team and resources to evaluate it rigorously. I look forward to working with James, Seth and the Board as we advance dotinurad through its registrational program and build Crystalys into a leading company focused on gout."

Mr. Fischer brings more than four decades of pharmaceutical and medical device leadership experience, including nearly 30 years in senior leadership roles at Johnson & Johnson, where his leadership roles included Company Group Chairman, North America Pharmaceuticals; Worldwide Franchise Chairman of Cordis Corporation; and President of Ortho-McNeil Pharmaceuticals.

He also served as Chief Executive Officer and director of Vivus, Inc., a publicly traded biopharmaceutical company. His extensive experience also includes serving on the boards of numerous publicly traded biopharmaceutical companies, including currently Milestone Pharmaceuticals Inc., and prior experience on the boards of Esperion Therapeutics Inc., Marinus Pharmaceuticals Inc., Agile Therapeutics Inc., and Spectrum Pharmaceuticals Inc. Through these roles, Mr. Fischer has developed significant expertise in corporate governance, strategic planning, and the oversight of companies navigating clinical development, commercialization and growth.

"Crystalys has made impressive progress advancing a differentiated urate transporter 1 (URAT1) inhibitor, one already supported by years of clinical use in approved markets, into a comprehensive registrational program in the United States and Europe," said Mr. Fischer. "Across my career bringing medicines to patients, I have seen how much a strong therapeutic opportunity benefits from disciplined development and thoughtful commercial planning. I am pleased to join at this stage and look forward to helping Crystalys advance dotinurad as a potential new option for people whose gout is not adequately controlled by current first-line therapy."

Ms. Reid brings 12 years of biotech and biopharmaceutical experience and has served as Executive Director, Operations and Business Development and a Co-Founder of Crystalys. Previously, she was Senior Director, Operations and Business Development at Aristea Therapeutics, which she co-founded in 2018 and where she played a key role in raising $138 million from global investors, including Novo Holdings. Earlier in her career, Ms. Reid held roles at Ardea Biosciences, Genentech and Tang Capital. As Chief Administrative Officer, she will help lead Crystalys' operations and organizational growth as the Company continues to scale and advances dotinurad through its registrational program.

About Gout

Gout is a chronic, progressive inflammatory disease caused by hyperuricemia, or excess uric acid in the blood, which can lead to urate crystal deposition, recurrent flares, joint damage and, in advanced cases, tophaceous disease. While many patients are initially treated with allopurinol, a xanthine oxidase inhibitor (XOI), a significant proportion do not achieve or maintain guideline-recommended serum uric acid (sUA) target levels or are unable to tolerate treatment. A substantial treatment gap remains for these patients, as currently approved second-line therapies, including febuxostat and probenecid, may be limited by safety, tolerability or other treatment-related considerations.

About Crystalys Therapeutics

Crystalys Therapeutics is a clinical-stage biopharmaceutical company focused on addressing the significant unmet medical needs of patients living with gout. Dotinurad is an oral, small-molecule product candidate designed to be a potent, once-daily, selective urate reabsorption inhibitor that inhibits URAT1 to reduce sUA by increasing renal uric acid excretion. Dotinurad has been approved and commercially available in Japan since 2020 and has since been approved in four other Asian countries. Crystalys is developing dotinurad in the United States and Europe as a second-line urate-lowering therapy for patients who fail to achieve or maintain target sUA levels after first-line therapy, allopurinol, or are intolerant to allopurinol. Crystalys is currently conducting its registration program, which includes the Phase 3 RUBY and TOPAZ trials, to compare dotinurad with allopurinol and evaluate sUA reduction and other clinically meaningful outcomes, including reductions in gout flares and tophus resolution. Beyond its Phase 3 program, Crystalys is also conducting a Phase 2 trial, AMETHYST, to evaluate dotinurad in participants who are intolerant to XOIs or who have failed uricase therapy. Crystalys Therapeutics is headquartered in San Diego, California.

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SOURCE Crystalys Therapeutics