Study to Find the Highest Safe Dose of Soluble Guanylate Cyclase (sGC) Activator, BAY 1211163 Administered as Multiple Doses by Inhalation to Patients Who Cannot Breathe by Their Own and Suffer From a Type of Lung Failure That Causes Fluid to Build up in the Lungs Making Breathing Difficult (ARDS)

Inclusion Criteria: * Intubated, mechanically ventilated moderate or severe ARDS patients \[diagnosed according to Berlin definition of ARDS, including PEEP ≥ 5 cmH2O, X-ray, with PaO2/FiO2 between 80 and 200 mmHg (inclusive). * Initial diagnosis of ARDS prior to study inclusion, confirmation of ongoing moderate or severe ARDS with PaO2/FiO2 between 80 and 200 mmHg (inclusive) during this time under maintained invasive mechanical ventilation. * Hypoxemia with PaO2/FiO2 between 80 and 200 mmHg (inclusive) maintained for at least 8 hours (recommend to be 12 hours) after screening, despite consent to follow recommendation on ventilator strategy and PEEP management. * Time from intubation must be ≤ 96h. * Male and non-pregnant female. * Informed consent of capable patient or, in case of patient being incapable of giving informed consent, consent for study inclusion will be sought according to applicable laws and regulations. Exclusion Criteria: * PaO2/FiO2 \> 200 mmHg or \< 80 mmHg at time of evaluation for inclusion. * Moribund participants not expected to survive 24 hours (clinical decision). * Expected duration of invasive mechanical ventilation less than 96 hours (clinical decision). * History of pneumectomy or lung transplant. * Current lung malignancy (including lung metastasis), or other malignancy requiring chemotherapy or radiation within the last month. * History of chronic kidney disease and requiring renal replacement therapy dialysis at screening and/or baseline. * Chronic liver disease Child-Pugh Class B and C. * Hypoalbuminemia - serum albumin \< 2.0 g/dL. * Acute left ventricular failure and/or Left Ventricular Ejection Fraction \< 30 %. * Severe bronchopulmonal fistula. * Clinical suspicion of pulmonary veno-occlusive disease. * Heart right-sided endocarditis, tumors or mass. * Rescue procedures already initiated at screening and/or Day 1. * Use of co-medications involving moderate and strong inhibitors for CYP2C8 liver enzymes one week before assignment to intervention or during intervention. * Off-label use of medication to treat Coronavirus SARS-CoV-2 virus unless recommended by scientific guidelines and accepted by DMC, investigator and sponsor. * Plan to participate or past participation (within 30 days prior to Study Day 1) in other interventional studies.