Restoring balance to the immune system.

Dr. Stephen Dilly, President, CEO, and Board Chair of Sonoma Biotherapeutics, brings forty years of executive management experience in the biopharmaceutical industry. Most recently, he served as President and CEO of Codexis (Nasdaq: CDXS) and continues to serve as Executive Chairman of its Board of Directors. At Codexis, Dr. Dilly led the transformation of the company from a life science tools provider into a full-service CDMO pioneering enzymatic oligonucleotide synthesis. Prior to Codexis, he served as President and CEO of Sierra Oncology (Nasdaq: SRRA) through its sale to GlaxoSmithKline for $1.9 billion. Dr. Dilly also served as CEO of Aimmune Therapeutics, acquired by Nestle Health Science for $2.6 billion. Previously, he served in executive roles at Genentech, Chiron and SmithKline Beecham.

Dr. Dilly has been associated with the development, approval and launch of more than twenty-five marketed drugs across multiple therapeutic areas. He holds both an MBBS (UK equivalent of MD) and a PhD in Cardiac Physiology from the University of London.

Stephen Hill joined the SonomaBio Board of Directors in June 2026. Mr. Hill is COO of Lyell Immunopharma, where he leads end-to-end development and manufacturing of cell therapy programs. He joined Lyell in 2019 to build its Technical Operations organization, establishing clinical manufacturing capabilities and advancing multiple programs into the clinic.

Mr. Hill brings deep expertise in biologics and cell therapy manufacturing, including large‑scale production, process scale‑up, global supply chain management, and operational excellence. Prior to Lyell, he was Head of Global Biologics Operations at AstraZeneca, overseeing manufacturing and supply across a global network of sites and commercial products.

Earlier in his career, Mr. Hill held multiple senior leadership roles at Amgen, where he led large‑scale biologics production, new product introductions, and global manufacturing initiatives.

Mr. Hill holds an MBA and a BS in Microbiology, as well as a BA in Political Science, from the University of Washington.

Toni Hoover joined the SonomaBio Board of Directors in February 2020. She is Director, Strategy, Planning, and Management for Global Health, at the Bill & Melinda Gates Foundation. Before joining the foundation in 2012, Dr. Hoover was Senior Vice President and Site Director at Pfizer Worldwide Research and Development, overseeing the operations of the company’s largest R&D laboratories located in Groton, Connecticut. She is a 25-year veteran of pharmaceutical R&D product development and management, having held positions in clinical research and operations, project and portfolio management, and laboratory and facilities management. While at Pfizer she led the global development of Lyrica® from exploratory development through early commercialization. She serves on several not-for-profit boards, including University of Washington Medical Center, New York Academy of Sciences, Xavier University of Louisiana, the Joyce Theater, and the Pacific Northwest Ballet.

Dr. Hoover received her BA, MA, and PhD in Psychology and Social Relations from Harvard University.

Terry Rosen joined the SonomaBio Board of Directors in February 2020. Dr. Rosen has been leading successful drug discovery and development organizations in the biotechnology and pharmaceutical industries for over 30 years.

In 2015, he co-founded Arcus Biosciences, a drug discovery company focused on the treatment of cancer by blocking tumor-induced immunosuppression. Previously, he was co-founder and CEO of Flexus Biosciences, focusing on small molecule drugs that reverse tumor immunosuppression. He has held several executive positions at Amgen and Tularik, as well as scientific and management positions at Pfizer and Abbott Laboratories. Dr. Rosen also serves on the boards of scientific institutions such as the Salk Institute Board of Trustees and the California Life Sciences Association.

Dr. Rosen received his PhD in Chemistry from UC Berkeley and his BS in Chemistry from University of Michigan.

Maggie Wilderotter joined the SonomaBio Board of Directors in February 2020. She is a senior advisor to several private equity and venture firms and serves on the public boards of Costco Wholesale Corporation, where she has been a director since 2015, and DocuSign, Inc. She also serves on the board of Tanium, Inc.

Ms. Wilderotter previously served as CEO and Chair of the Grand Reserve Inn from 2016 to 2023, and as Interim CEO of DocuSign from June to October 2022. Earlier in her career, she was Chairman and CEO of Frontier Communications from 2004 to 2015, then Executive Chairman until 2016, leading the company’s growth from a regional telephone provider into a national broadband, voice, and video operator.

Prior to Frontier, Ms. Wilderotter was Senior Vice President at Microsoft Corporation, and from 1997 to 2002 was President and CEO of Wink Communications, an interactive telecommunications and media company. Over her career, she has served on the boards of more than thirty public companies, including Sana Biotechnology, Fortinet, Xerox, DreamWorks Animation, Cadence Design Systems, Hewlett Packard Enterprise, Procter & Gamble, and Lyft.

Mrs. Wilderotter holds a BA in Economics from the College of the Holy Cross. She has been awarded an Honorary Doctor of Engineering degree from the Stevens Institute of Technology and an Honorary Doctor of Laws degree from the University of Rochester.

Carlos Solórzano, joined the SonomaBio Board of Directors in April of 2025. He is a Principal in the Biotech Private Equity team at Ally Bridge Group. Prior to Ally Bridge, Mr. Solórzano was in the investment teams at S32 and Pivotal bioVenture Partners where he participated or led over a dozen investments in biotech companies including Akouos (acquired by Eli Lilly), Avalyn, Evommune, Plexium, Arkuda, Obsidian and Nested Therapeutics.

Prior to his investment roles, Mr. Solórzano was an Associate Director in the corporate strategy and business development team at Ultragenyx Pharmaceutical where he worked on competitive intelligence, as well as portfolio, commercial and BD strategy.

Prior to Ultragenyx, Mr. Solórzano worked as an equity research associate at Deutsche Bank and Oppenheimer & Co. covering smid- and large-cap biotech companies.

He earned his PhD in Pharmacology from UC Irvine and was an NIH postdoctoral scholar at UC San Francisco where he investigated the neurobiology of pain and itch. He received his BS in Chemical Engineering from Cal Poly Pomona.

Katina Dorton, joined the SonomaBio Board of Directors in August 2022. She currently serves on the Board of Directors of Fulcrum Therapeutics, TScan Therapeutics, Inc., Prelude Therapeutics Incorporated, and Mallinckrodt, plc and previously served on the Board of Pandion Therapeutics until its acquisition by Merck in 2021 and US Ecology until its acquisition by Republic Services, Inc. in 2022. Ms. Dorton has held CFO positions at several biotechnology companies, including NodThera Inc, Repare Therapeutics, AVROBIO, and Immatics GmbH. Earlier in her career, Katina served as a managing director in investment banking for Morgan Stanley and Needham & Company and as an attorney at Sullivan & Cromwell.

Ms. Dorton received her JD from the University of Virginia School of Law, her MBA from George Washington University, and her BA from Duke University.

John Davis, joined the SonomaBio Board of Directors in August 2022. He is strategic and clinical development advisor to Ouro Medicines and currently serves on the Board of Directors of Nucleome Therapeutics. He previously served on the Board of Directors at Rheos Medicines and strategic advisor to Oak Hill Bio. He is President of Norte Health Consulting. He is also an attending volunteer physician at the Boston VA Medical Center Rheumatology Clinic.

Previous roles include Head of Research and Development/CMO and Member of the Scientific Advisory Board at Magenta Therapeutics; Senior Vice President of Early Clinical Development at Pfizer; Global Head of Immunology and Vice President at Baxalta (Acquired by Shire), Therapeutic Area Head and Senior Group Director Inflammation, Cardiovascular/Metabolism gRED at Genentech, and Professor of Clinical Medicine and Director of Clinical Research Center, Lupus Clinic, and Spondylitis Clinic at UCSF. He has authored over 120 publications and book chapters and has held international leadership positions in his areas of research focus in autoimmune disease.

Dr. Davis earned an MD from the University of Maryland, an MPH in Epidemiology from UC Berkeley, and an MS in Anatomy from the University of Maryland. He trained in Internal Medicine and Rheumatology/Autoimmune Disease at UCSF and NIH. He is a Fellow in both the American College of Physicians and the American College of Rheumatology.