Safety, Tolerability and Efficacy Of S-1226 in Moderate Severity Covid-19 Bronchiolitis/Pneumonia

This is a randomized, open-label, controlled, Phase II proof of concept study to evaluate the safety, tolerability and efficacy of S-1226 in which hospitalized subjects with moderate severity COVID-19 Bronchiolitis/Pneumonia. 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, vapour and liquid aerosol penetrates obstructed airways, resulting in rapid bronchodilation, enhanced blood oxygenation, improved mucus clearance and reduction of work of breathing The primary objective of this study is to evaluate the safety and tolerability of S-1226 composed of perflubron (PFOB) with ascending doses of carbon dioxide (4%, 8% and 12% CO2) in hospitalized subjects with moderate severity COVID-19 bronchiolitis/pneumonia. The secondary objective is to establish proof of concept that S-1226 is effective in restoring lung function in hospitalized subjects with moderate severity COVID-19 bronchiolitis/pneumonia. The study will consist of three parts: screening period, Dosing and evaluation, follow up period. 1. During the screening period, subjects will undergo safety assessments and their eligibility to participate will be confirmed. Eligible subjects will then be randomly assigned to either the treatment arm (S-1226 + Standard of Care arm) or the non-treatment arm (Standard of Care only). 2. The dosing and evaluation period will take place over 5 days of with two doses per day. Subjects who are randomized to receive S-1226 will be started on a dose level of S-1226 (4%). If tolerated, subjects will progress from 4%, followed by 8%, and then 12%. The highest tolerated dose will then be used for the remainder of the treatment period. All doses incorporate 3mL PFOB and will be administered over a 3-4 minute treatment period. Any enrolled subject randomized to receive S-1226 will not be required to interrupt any SOC treatment which includes supplementary oxygen. Each S-1226 dose will be administered as inhaled gas \& vapour using a Circulaire II hybrid system specifically adapted with the addition of an absolute aerosol filter installed at the site of aerosol generation. This filter removes all perflubron aerosol so that in this trial the S-1226 Gaseous Delivery System delivers an inhaled drug comprising gas (CO2 in air) and vapour (perflubron). In addition, the S-1226 Gaseous Delivery System includes a high efficiency bacterial/viral filter to scavenge any patient-generated exhaled aerosol. 3. Follow up Period will 28 days after the first dose of S1226 has been administered.