Low Dose Radiation Therapy for COVID-19 Pneumonia

Inclusion Criteria: * Laboratory Diagnosis of COVID-19 based within 14 days of enrollment. * CT or radiographic findings typical of COVID-19 pneumonia within 5 days of enrollment * Receiving ICU-based mechanical ventilation * Life expectancy ≥ 24 hours, as judged by investigator * Hypoxemia defined as a Pa/FIO2 ratio \< 300 or SpO2/FiO2 \< 315 * Signed informed consent by patient or his or her legal/authorized representative Exclusion Criteria: * Moribund with survival expected \< 24 hours, as judged by investigator and treating team * Expected survival \< 30 days, as judged by investigator and treating team, due to chronic illness present prior to COVID infection * Patient or legal representative not committed to full disease specific therapy, i.e. comfort care (DNRCCA is allowed) * Treatment with immune suppressing medications in the last 30 days (steroids for acute respiratory distress syndrome or septic shock allowed) * Presumed COVID-associated illness greater than 14-days * Inpatient admission greater than 14-days * Patient deemed unsafe for travel for radiation therapy * Chronic hypoxemia requiring supplemental oxygen at baseline * Documented active connective tissue disease (scleroderma) or idiopathic pulmonary fibrosis * History of prior radiation therapy resulting in ≥grade 2 radiation pneumonitis within 365 days of enrollment * Active or history of prior radiation to the thorax completed within 180 days of enrollment (skin or surface only skin treatments are acceptable) * Known active uncontrolled bacterial or fungal infections of the lung. * Active cytotoxic chemotherapy * Females who are pregnant or have a positive pregnancy test * Breast feeding * Note: concurrent administration of convalescent immune plasma therapy either on clinical trial or as a standard therapy not an exclusion criterion, but will be noted