Dr. Amie Phinney reports

DEFENCE THERAPEUTICS STRENGTHENS RADIOPHARMACEUTICAL LEADERSHIP WITH APPOINTMENT OF DR. RYAN SIMMS AS CHIEF OPERATING OFFICER AND HEAD OF RADIOPHARMACEUTICAL PROGRAMS

Defence Therapeutics Inc. has appointed Dr. Ryan Simms, PhD, as chief operating officer and head of radiopharmaceutical programs, strengthening the company's leadership and development capabilities as it advances its radiopharmaceutical drug conjugate (RDC) programs.

"Ryan brings more than 20 years of experience in advancing targeted radiopharmaceuticals from discovery through first-in-human clinical studies, combined with the operational leadership needed to translate complex science into executable development programs," said Dr. Amie Phinney, president and chief executive officer of Defence Therapeutics. "His expertise will be instrumental in accelerating our radiopharmaceutical programs and expanding the potential of the Accum platform."

Dr. Simms brings extensive experience in radiopharmaceutical development and operations, with a record spanning the advancement of targeted radiopharmaceuticals from discovery through clinical development. He held key leadership roles at Fusion Pharmaceuticals, where he directed chemistry, radiochemistry, clinical manufacturing and external partnerships supporting multiple clinical-stage programs. Fusion Pharmaceuticals became a leading player in targeted radiopharmaceuticals and was acquired by AstraZeneca in 2024 for approximately $2-billion (U.S.).

Dr. Simms also held leadership roles at Abdera Therapeutics and the Centre for Probe Development and Commercialization (CPDC), building expertise across CMC (chemistry, manufacturing and controls) strategy, manufacturing, isotope supply, radiochemistry and technical operations. This combination of scientific, development and operational experience will support his broader responsibilities as COO as Defence scales its radiopharmaceutical programs and operations. Dr. Simms holds a PhD in engineering from Queen's University and completed postdoctoral research in chemistry at the University of Toronto.

"I am excited to join Defence at a time when the company is expanding its capabilities and ambitions in radiopharmaceuticals," said Dr. Simms. "We have promising candidates in development and a clear path to advance them. Our immediate priority is to select a lead candidate and move it systematically through preclinical characterization, while establishing the CMC and manufacturing framework required to support its progression toward the clinic. More details will come soon."

Dr. Simms's appointment follows the recent appointment of Dr. Phinney as president and CEO and the opening of Defence's new office at McMaster Innovation Park in Hamilton, at the heart of one of Canada's leading radiopharmaceutical ecosystems. Together, these milestones position Defence for its next phase of growth.

About Defence Therapeutics Inc.

Defence Therapeutics is a publicly traded biotechnology company committed to making cancer treatment more effective and safer. Using its Accum precision drug delivery platform, Defence is working to enhance the potency of ADCs and other complex biologics at lower doses, with the goal of reducing side effects and improving access to advanced therapies. By pursuing cutting-edge science and collaborating with pharma and biotech partners, Defence strives to bring transformative therapies to patients who need them most.

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