Atossa Therapeutics Strengthens Clinical Leadership Team with the Addition of Two Experienced Biopharma Executives

Kathy Puyana Theall, M.D. and Adebola Giwa, M.D. bring deep expertise across oncology, rare diseases, and global clinical development to support advancement of Atossa's pipeline

SEATTLE, March 19, 2026 /PRNewswire/ -- Atossa Therapeutics, Inc. (Nasdaq: ATOS) ("Atossa" or the "Company"), a clinical-stage biopharmaceutical company developing novel therapies in oncology and other rare diseases, today announces the engagement of Kathy Puyana Theall, M.D., as Medical Director - Breast Oncology, and Adebola Giwa, M.D., as Medical Director - Rare Diseases.  The addition of these two highly experienced physicians and clinical leaders meaningfully strengthens Atossa's ability to execute on its (Z)-endoxifen development strategy across both breast cancer and rare disease programs, including McCune-Albright syndrome (MAS) and Duchenne Muscular Dystrophy (DMD), as the Company advances toward key clinical and regulatory milestones.

"These additions reflect our continued investment in building a world-class clinical organization as we advance our pipeline," said Dr. Steven Quay, Atossa Therapeutics Chief Executive Officer. "Kathy brings a proven track record in late-stage oncology development and regulatory approvals in breast cancer, while Adebola contributes deep expertise in endocrine and rare disease clinical development, with extensive experience advancing innovative therapies from early clinical stages through global execution. Together, they significantly enhance our ability to efficiently advance our programs and deliver meaningful outcomes for patients."

Kathy Puyana Theall, M.D.
Dr. Theall is a board-certified medical oncologist with more than 24 years of experience spanning academic medicine and the biopharmaceutical industry, including over a decade in senior clinical development roles. She brings deep expertise in breast cancer drug development and has contributed to programs supporting multiple global regulatory approvals.

Most recently, Dr. Theall served as Vice President of Clinical Development – Breast Cancer at Stemline-Menarini, where she led clinical strategy and execution supporting the FDA approval of ORSERDU™ (elacestrant) in 2023 and subsequent global approvals. She also led multiple clinical trials, including the Phase Ib/II ELEVATE umbrella study evaluating combination therapies in advanced breast cancer.

Previously, Dr. Theall held senior roles at Pfizer Inc., where she contributed to the clinical development of IBRANCE® (palbociclib), including the PALOMA trials that supported both accelerated and full approvals. She began her career in academic medicine, serving in leadership roles at Tufts Medical Center and as a clinical investigator across more than 40 oncology studies.

"Atossa is at an important stage of growth," said Dr. Theall. "The company's commitment to advancing innovative therapies in breast cancer strongly aligns with my experience and passion, and I look forward to contributing to the continued development of its pipeline."

Adebola Giwa, M.D. 
Dr. Giwa is a board-certified pediatrician who trained in pediatric endocrinology at Johns Hopkins and later served on the faculty. He is a physician–scientist and clinical development leader with more than 15 years of experience across academic medicine and the biopharmaceutical industry and brings deep expertise in endocrine, musculoskeletal, and rare disease drug development. He has led the strategy and execution of global clinical programs across multiple therapeutic areas, including endocrinology, musculoskeletal disorders, and nephrology

Most recently, Dr. Giwa served as Senior Medical Director at Maze Therapeutics, where was the primary clinical lead for a genetic chronic kidney disease program and additional early-stage assets, with responsibility for overall clinical strategy, global trial design, safety oversight, and regulatory positioning. He played a key role in portfolio prioritization and executive decision making and led clinical execution across North America and Europe.

Prior to Maze, Dr. Giwa was Medical Director at Angitia Biopharma, where he led a global Phase 1 program and advanced the asset into Phase 2, and earlier served at Ascendis Pharma, where he managed multiple global clinical trials across Phase 1 through Phase 3 development.

Dr. Giwa has extensive experience as a medical monitor and clinical lead, with deep involvement in protocol design, regulatory interactions, data monitoring committees, and cross-functional program leadership. He is also the founder of AdeBolus Medical Consulting, where he advises biopharma companies on clinical and translational strategy.

"I'm excited to join Atossa and contribute to the advancement of its clinical programs," said Dr. Giwa. "The opportunity to help develop innovative therapies for patients with significant unmet medical needs is incredibly meaningful, and I look forward to working with the team to advance the company's pipeline and deliver high-quality clinical data to bring new treatments forward."

About Atossa Therapeutics

Atossa Therapeutics, Inc. (Nasdaq: ATOS) is a clinical-stage biopharmaceutical company developing innovative medicines in oncology and other areas of significant unmet need. The Company's lead product candidate, (Z)-Endoxifen, is currently in development across several clinical settings. More information is available at https://atossatherapeutics.com.

Forward-Looking Statements

This press release contains certain "forward-looking statements" within the meaning of applicable securities laws, including but not limited to, our expectations regarding the Company's development and regulatory strategy and related milestones, the potential indications that the Company may pursue for (Z)-Endoxifen, the potential for (Z)-Endoxifen to receive regulatory approval and the timing thereof, expectations regarding the design, enrollment, data, timing, results and outcomes of the Company's clinical studies, and the potential market and growth opportunities for the Company. Words such as "expect," "potential," "continue," "may," "will," "should," "could," "would," "seek," "intend," "plan," "estimate," "anticipate," "believe," "design," "predict," "future," or other similar expressions or statements regarding intent, belief or current expectations, are forward-looking statements.

Forward-looking statements in this press release are subject to risks and uncertainties that may cause actual results, outcomes, or the timing of actual results or outcomes to differ materially from those projected or anticipated, including, without limitation, risks and uncertainties associated with: our ability to successfully execute our strategy to shorten our clinical development timelines for oncology indications, DMD indication, or other indications for our lead program, (Z)-Endoxifen; expected timing, completion and results of our preclinical studies, clinical trials and research and development programs; the unpredictable relationship between preclinical study results and clinical study results; the timing or likelihood of regulatory filings and approvals; the outcome or timing of necessary regulatory approvals; our ability to maintain compliance with Nasdaq listing requirements; our ability to establish and maintain intellectual property rights covering our products; the impact of general macroeconomic conditions on our business; our ability to raise capital; and other risks and uncertainties detailed from time to time in Atossa's filings with the SEC, including, without limitation, its Annual Reports on Form 10-K and Quarterly Reports on Form 10-Q.

Forward-looking statements are presented as of the date of this press release. Except as required by law, we do not intend to update any forward-looking statements.

SOURCE Atossa Therapeutics Inc