Atossa Therapeutics Announces Ovarian Cancer Patient has Begun Treatment with Oral Endoxifen under FDA’s Expanded Access Pathway

SEATTLE, April 08, 2021 (GLOBE NEWSWIRE) -- Atossa Therapeutics, Inc. (Nasdaq: ATOS), a clinical-stage biopharmaceutical company seeking to discover and develop innovative medicines in areas of significant unmet medical need in oncology and infectious diseases, today announced that an ovarian cancer patient has begun treatment with Atossa’s proprietary oral Endoxifen. The FDA previously issued a “Safe to Proceed” letter under their expanded access pathway, permitting the use of Atossa’s oral Endoxifen in this patient. The patient is being treated at the University of Washington Medical Center by Dr. Barbara Goff, Surgeon-in-Chief.

“The patient has recurrent ovarian cancer and did not tolerate tamoxifen, which is sometimes prescribed for ovarian cancer as well as breast cancer,” commented Steven Quay, M.D., Ph.D., Atossa’s President and CEO. “The patient recently underwent functional molecular genomic testing using 3D tumor organoid cultures grown in the laboratory from the patient’s tumor to help determine potential therapies. This testing revealed that the combination of Endoxifen and alpelisib produced an exceptional tumor response. We will follow the progress of this patient and consider additional clinical studies in patients with ovarian cancer.”

Under the FDA expanded access program, the use of Atossa's proprietary oral Endoxifen is restricted solely to this patient.

About FDA Expanded Access

Sometimes called "compassionate use," expanded access is a potential pathway for a patient with serious disease or condition, or an immediately life-threatening condition, to gain access to an investigational medical product (drug, biologic, or medical device) for treatment outside of clinical trials when no comparable or satisfactory alternative therapy options are available. For more information about this process, please see the FDA website: FDA Expanded Use Website

About Atossa's Proprietary Endoxifen

Endoxifen is an active metabolite of tamoxifen, which is an FDA-approved drug to treat ovarian and breast cancer. Tamoxifen itself must be broken down by the liver into active compounds (metabolites), of which Endoxifen is the most active. In third party preclinical studies, endocrine-sensitive and letrozole-resistant breast tumors, Z-endoxifen resulted in robust antitumor and antiestrogenic activity compared to tamoxifen and aromatase inhibitor monotherapy.