Inhaled high dose nitric oxide is a safe and effective respiratory treatment in spontaneous breathing hospitalized patients with COVID-19 pneumonia

•We delivered 160 ppm of inhaled nitric oxide (iNO) twice daily to hospitalized patients with mild to moderate COVID-19 pneumonia.•Respiratory rate decreased during iNO treatments in patients who were tachypneic at the beginning of each administration.•Oxygen saturation increased during iNO treatments in patients who were hypoxemic at the beginning of each administration.•No patient had hypoxemia, hypotension, tachycardia, or methemoglobinemia, either during or after iNO treatment.•No patients were readmitted within 28 days or had long term COVID-19 sequelae.