Atossa Therapeutics Announces Completion of Part B of Clinical Study of AT-H201


SEATTLE, April 20, 2022 (GLOBE NEWSWIRE) -- Atossa Therapeutics, Inc. (Nasdaq: ATOS), a clinical stage biopharmaceutical company seeking to develop innovative medicines in areas of significant unmet medical need in oncology and infectious diseases with a current focus on breast cancer and COVID-19, today announces it has completed enrolling participants in Part B of its Phase 1/2a clinical study of AT-H201 in Australia, consisting of multiple ascending dose cohorts in healthy participants. AT-H201 is being developed as an inhalation therapy for moderately to severely ill hospitalized COVID-19 patients and for “long-haul” patients with post-infection pulmonary disease.

“Part B of the study was successfully completed and, subject to approval from the ethics committee, we will now proceed to enroll the next group of participants,” said Steven Quay, M.D., Ph.D., Atossa’s CEO and President. “Despite widespread availability of vaccines, many areas of the world are seeing a recent surge in COVID-19 cases. There continues to be a strong need for additional therapies to combat COVID-19.”

The Phase 1/2a placebo-controlled study will enroll a total of 60 healthy participants and moderately-ill hospitalized COVID-19 patients. The study has four parts: Part A - a single ascending dose part; Part B - a multiple ascending dose part; Part C - a combination part in healthy individuals; and Part D - a combination in COVID-19 infected patients. Parts A, B and C of the study are being conducted by Avance Clinical Pty Ltd., a leading Australian clinical research organization. Commencing Parts C and D of the study is subject to additional approvals from the Australian Human Research Ethics Committee.

AT-H201 is a proprietary combination of two drugs previously approved by the FDA to treat other diseases and by other administration routes. AT-H201 is intended to be inhaled via nebulizer to improve compromised lung function for moderately to severely ill, hospitalized COVID-19 patients, and for “long-haul” patients with post-infection pulmonary disease. In May 2020, we completed in vitro testing of AT-H201, which showed that the components of AT-H201 inhibit SARS-CoV-2 infectivity of VERO cells, a standard cell type being used to study infectivity of the coronavirus.

The Phase 1/2a study in Australia and other clinical studies must be successfully completed and regulatory approvals must be obtained before AT-H201 may be commercialized. No assurance can be given that studies will be successful or that regulatory approvals will be obtained.


Atossa Therapeutics, Inc. is a clinical-stage biopharmaceutical company seeking to develop innovative medicines in areas of significant unmet medical need in oncology and infectious diseases with a current focus on breast cancer and COVID-19. For more information, please visit


Forward-looking statements in this press release, which Atossa undertakes no obligation to update, are subject to risks and uncertainties that may cause actual results to differ materially from the anticipated or estimated future results, including, without limitation, statements regarding the satisfaction of closing conditions relating to the offering and the anticipated use of proceeds from the offering, the risks and uncertainties associated with any variation between interim and final clinical results, actions and inactions by the FDA, the outcome or timing of regulatory approvals needed by Atossa including those needed to commence and continue studies of AT-H201, AT-301 and Endoxifen, lower than anticipated rate of patient enrollment, estimated market size of drugs under development, the safety and efficacy of Atossa’s products, performance of clinical research organizations and investigators, obstacles resulting from proprietary rights held by others such as patent rights, whether reduction in Ki-67 or any other result from a neoadjuvant study or reduction of breast density will be approvable endpoints for oral Endoxifen, and other risks detailed from time to time in Atossa’s filings with the Securities and Exchange Commission, including without limitation its periodic reports on Form 10-K and 10-Q, each as amended and supplemented from time to time.


Atossa Therapeutics, Inc.
Kyle Guse, CFO and General Counsel
Office: (866) 893-4927

Core IR
Office: (516) 222-2560