Dosing Completed in Part C of Atossa’s Phase 1/2a Study of AT-H201 in Healthy Volunteers

SEATTLE, July 28, 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 dosing participants in Part C of its Phase 1/2a clinical study of its proprietary inhalation therapy (or, AT-H201) in Australia.  

AT-H201 consists of two drugs previously approved by the FDA to treat other diseases. AT-H201 is intended to be inhaled via nebulizer with the goal of preventing or reducing lung injury that may be caused by fibrin deposition, fluid build-up and secondary infection.

Part C of the study involved administering the two drugs in succession in healthy volunteers. The study originally included a Part D which was designed to assess the effects of the treatment regimen in hospitalized COVID-19 patients with moderate illness. However, due to the rapidly shifting COVID-19 treatment landscape and the introduction of effective vaccines limiting hospitalizations, Atossa has evaluated indications for AT-H201 beyond COVID-19 patients, including treating and/or preventing lung injury in patients undergoing certain cancer treatments.

Rather than conducting Part D of the Phase 1/2a clinical study, Atossa now plans to shift the development of AT-H201 to closely align with its oncology focus by continuing the development in patients with compromised lung-function due to the damaging effects of cancer treatment. For example, radiation treatment can lead to radiation induced lung injury, which is poorly treated with current therapies and is often irreversible. Furthermore, radiation damage can limit the overall success of lung cancer treatment leading to a reduction in efficacy and poor disease control. AT-H201 has pharmacological properties to potentially curtail excessive radiation-induced lung injury without compromising standard of care cancer therapy for cancer patients. AT-H201 is designed to prevent and reduce dose-limiting toxicities, and enable a more durable therapeutic tumor response for cancer patients receiving pulmonary radiation.

“We are happy to have completed Parts A, B and C of the clinical trial and look forward to evaluating the results,” said Steven Quay, M.D., Ph.D., CEO and President of Atossa. “With widespread availability of SARS-CoV-2 vaccines and other therapies now approved to treat COVID-19, we believe that altering the development pathways for AT-H201 in patients with compromised lung-function resulting from radiation may fill a compelling unmet medical need and create more value for our stockholders.“ Based on our work to date with AT-H201, we believe we can quickly initiate a clinical study in this setting and we plan to announce our next steps in the fourth quarter,” concluded Dr. Quay.

Radiation Induced Lung Injury (RILI)

RILI is damage to the lungs caused by ionizing radiation administered to treat cancer. RILI is a significant issue for patients undergoing radiation treatment for various forms of cancer and is often irreversible. For instance, RILI affects 30-40% of lung cancer patients, and ~35% of esophageal cancer patients. In non-small cell cancer patients receiving concurrent chemotherapy and radiation therapy the incidence of RILI is estimated to be greater than 60%. Although Atossa has not finalized the protocol for this new trial we believe RILI affects a significant number of patients across multiple cancer types and there is a meaningful need for new treatments.

About AT-H201

AT-H201 is a proprietary sequential dosing regimen of two 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.

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

About Atossa Therapeutics

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.

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Forward-Looking Statements

Forward-looking statements in this press release, which Atossa undertakes no obligation to update, are subject to risk 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 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 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.

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Atossa Therapeutics, Inc.

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