Safety, Tolerability and Efficacy of S-1226 in Post-COVID-19 Subjects With Persistent Respiratory Symptoms.

This is a randomized, placebo-controlled, phase II proof of concept study to evaluate the safety, tolerability and efficacy of S-1226 in Post-COVID-19 subjects (n≤48) with persistent respiratory symptoms. S-1226 contains a potent, safe and well-tolerated bronchodilator gas (extrinsic carbon dioxide or CO2) and perflubron (PFOB), a synthetic surfactant that facilitates restoration of surfactant function and mucus clearance. The inhaled S-1226 combination of gas, vapor and liquid aerosol penetrates obstructed airways, resulting in rapid bronchodilation, enhanced blood oxygenation, improved mucus clearance and reduction of work of breathing. Primary objective of this study is to evaluate the safety and tolerability of S-1226 composed of perflubron with 8% carbon dioxide in subjects with persistent post acute COVID-19 respiratory symptoms. The secondary objective is to establish proof of concept that S-1226 is effective in normalizing lung symptoms, including cough, breathlessness and lung function in subjects with persistent post-acute COVID-19 respiratory symptoms. The study will consist of three parts: screening and randomization period, Treatment and evaluation, follow up period. 1. Screening, and randomization: subjects will be randomized (1:1) to either receive placebo or S-1226 treatment. 2. Treatment and evaluation period: subjects will receive either placebo -medical grade air with 3ml saline (0.9% NaCl) - or S-1226 (8% CO2) for 7 days twice daily. A single dose of S1226 (8%) will be administered over 3-4 minutes at each visit. Subjects will have the option to receive at home treatments once they been trained and verified as competent in handling study equipment. 3. A follow up period 7 days after final treatment.