SEATTLE , July 29, 2025 /PRNewswire/ -- Atossa Therapeutics, Inc. (NASDAQ: ATOS), a clinical-stage biopharmaceutical company developing innovative medicines in oncology, today announced positive written feedback from the U.S. Food and Drug Administration (FDA) regarding the company's proposed dose optimization trial of

-endoxifen for the treatment of estrogen receptor positive (ER+), human epidermal growth factor receptor 2 negative (HER2-) metastatic breast cancer. With the FDA's feedback, Atossa is energized and moving quickly to advance

-endoxifen in metastatic breast cancer.