The goal of this clinical trial is to learn if R-3750 is safe in \[in patients with late-stage, non-resolving Acute Respiratory Distress Syndrome (ARDS) . The main question\[s\] it aims to answer are:
1. the favorable safety profile 2. clinical improvement that includes reduced ventilator dependence and improved lung function.
Participants will be given oral capsules daily and/or enteral nasogastric or orogastric (NG/OG tube) if necessary.
Age ≥18 years at the time of consent.
Hypoxemia defined as PaO2/FiO2 ≤300 mmHg, or SpO2/FiO2 ≤315 if SpO2 is ≤97%;
Bilateral pulmonary infiltrates/opacities on chest imaging consistent with pulmonary edema or fibroproliferative lung injury and not fully explained by pleural effusions, lobar collapse, or atelectasis;
Requirement for positive pressure respiratory support, including invasive mechanical ventilation via endotracheal tube;
Age <18 years.
More than 28 days since onset of ARDS at the time of enrollment.
ARDS that is clearly resolving rapidly, in the judgment of the investigator, such that enrollment in a 28-day rescue-therapy study is not clinically appropriate.
Pregnancy or breastfeeding.