Atossa Therapeutics, Inc. develops and markets medical devices, laboratory tests, and therapeutics to address breast health conditions in the United States. Its lead program is the development of Endoxifen, conducting two Phase II studies, which is an active metabolite of tamoxifen to treat and prevent breast cancer. The company is also developing intraductal microcatheter technology to potentially target the delivery of therapies, including fulvestrant, immunotherapies, and Chimeric Antigen Receptor T-cell therapies, directly to the site of breast cancer. Its medical devices also include the ForeCYTE Breast Aspirator and the FullCYTE Breast Aspirator, which collect specimens of nipple aspirate fluid for cytological testing. The company was formerly known as Atossa Genetics Inc. and changed its name to Atossa Therapeutics, Inc. in January 2020. Atossa Therapeutics, Inc. was founded in 2009 and is headquartered in Seattle, Washington.