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Atossa Therapeutics, Inc. is a clinical-stage biopharmaceutical company developing innovative medicines in areas of significant unmet medical need in oncology with a current focus on breast cancer and lung injury caused by cancer treatments.

Atossa Therapeutics is developing a drug “(Z)-endoxifen” to reduce mammographic breast density and, for patients who have recently been diagnosed with the most common type of breast cancer, to reduce tumor activity prior to surgery. Study by others have shown that reducing breast density can reduce the risk of breast cancer. (Z)-Endoxifen has the potential to work in all three areas of the Breast Cancer Paradigm: to mitigate breast cancer risk (by reducing the density of breast tissue); to reduce the cancer cell activity before surgery; and to reduce the risk of recurrent or new breast cancer after the initial treatment. Atossa is also developing oral (Z)-endoxifen in the “window of opportunity” between diagnosis of breast cancer and surgery. For these newly diagnosed patients, taking oral (Z)-Endoxifen before surgery may “turn down” the cancer cell activity. (Z)-Endoxifen has been identified as a key tamoxifen metabolite that helps reduce the risk of getting future breast cancer. Studies have shown that increasing the levels of (Z)-endoxifenin breast cancer patients reduces the risk of future recurrence. Atossa’s proprietary Oral form of (Z)-Endoxifen was the subject of a comprehensive Phase 1 clinical study in healthy women in Australia. All objectives from this study were successfully met. In addition, Atossa’s Oral (Z)-Endoxifen was subject of an open-label Phase 2 clinical study administered in the “window of opportunity” between diagnosis of breast cancer and surgery. Positive results were achieved with the patients enrolled.  

Atossa is led by accomplished scientist and entrepreneur, Dr. Stephen Quay, MD, PhD. Dr. Quay has served as Chief Executive Officer, President and Chairman of the Board of Directors of the Company since the Company was incorporated in April 2009. Dr. Quay is certified in Anatomic Pathology with the American Board of Pathology, completed both an internship and residency in anatomic pathology at Massachusetts General Hospital, a Harvard Medical School teaching hospital, and is a former faculty member of the Department of Pathology, Stanford University School of Medicine. Dr. Quay is a named inventor on 87 U.S. patents, 130 pending U.S. patent applications, and is named inventor on patents covering five pharmaceutical products that have been approved by the U.S. Food and Drug Administration. Dr. Quay received an M.D. in 1977 and a Ph.D. in 1975 from the University of Michigan. He received his B.A. degree in biology, chemistry and mathematics from Western Michigan University in 1971. He was selected to serve on the Company’s Board of Directors because of his role as a founder of the Company, as well as his qualifications as a physician and the principal researcher overseeing the clinical and regulatory development of the Company’s pharmaceutical programs. View Dr. Quay’s TedX Talk “How to Be Smart When You’re Dense: Preventing Breast Cancer by 2030.”



vista's key points

  • Atossa is led by Dr. Stephen Quay, MD, PhD. who has invented 7 FDA-approved pharmaceuticals which have helped over 80 million people.
  • Atossa Therapeutics is a clinical stage biopharmaceutical company seeking to discover and develop innovative medicines in areas of significant unmet medical need.
  • Atossa’s current focus is on breast cancer and radiation-induced lung injury.
  • Atossa believes their innovative therapies can benefit cancer patients receiving radiation treatment and can transform breast cancer treatment – with the goal of preventing breast cancer from developing in the first place.
  • Atossa is developing a drug “(Z)-endoxifen” to reduce mammographic breast density and, for patients who have recently been diagnosed with the most common type of breast cancer, to reduce tumor activity prior to surgery.
  • In October 2022, the U.S. Food and Drug Administration (FDA) authorized the initiation of our EVANGELINE study, a Phase 2 trial of (Z)-endoxifen and Exemestane + Goserelin as neoadjuvant treatment in premenopausal women with ER+/HER2- breast cancer.
  • While there are several FDA-approved neoadjuvant therapies for ER- breast cancers, few exist for the ER+ patients, which account for approximately 78% of breast cancers. They expect to enroll approximately 175 patients at up to 25 sites across the United States.
  • Atossa's position was further strengthened in March, 2022 when the U.S. Patent and Trademark office issued U.S. Patent No. 11,261,151 (the ‘151 Patent). Titled “Methods for Making and Using Endoxifen,” the ‘151 Patent is directed to compositions of storage-stable (Z)-endoxifen and methods of treating hormone-dependent breast disorders using the storage-stable (Z)-endoxifen. The ‘151 Patent is estimated to expire in 2038.
  • Atossa's proprietary Selective Estrogen Receptor Modulator (SERM), (Z)-endoxifen, will be evaluated in a new study arm of the ongoing I-SPY 2 clinical trial & collaborated among academic investigators from major cancer research centers across the United States, Quantum Leap Healthcare Collaborative, the U.S. Food and Drug Administration, and the Foundation for the National Institutes of Health (FNIH) Cancer Biomarkers Consortium.
  • As of December 31, 2022, Atossa confirmed it had cash, cash equivalents & restricted cash totaling $111 Million.

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