Atossa Therapeutics, Inc. announced it is advancing to enroll 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. The nebulized formulation, 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 A of the study, which consisted of a single ascending dose group of 4 cohorts of healthy participants, has now been completed.

The Australian Human Research Ethics Committee has reviewed the safety data from Part A and has approved the study to proceed to Part B. 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 4 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. The study is being conducted by Avance Clinical Pty Ltd. 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 a nebulizer to improve compromised lung function for moderate to severely ill, hospitalized COVID-19 patients and for “long-haul” patients with post-infection pulmonary disease. In May 2020, the company completed in vitro testing of AT-H201 which showed that the components of AT-H201 inhibit SARS-CoV-2 infectivity of VERO cells, which is a standard cell type being used to study infectivity of the coronavirus.