Low Dose Whole Lung Radiation Therapy for Patients With COVID-19 and Respiratory Compromise

The primary outcome is the mortality rate 30 days after the ICU-based mechanical ventilation initiation.Based on current data available, the mortality rate for ventilated patients is assumed to be 80% in the current design. An interim futility analysis will be conducted after 16 evaluable patients have received the ultralow dose-whole lung radiation therapy (ULD-WLRT). If at least 3 patients survive for at least 30 days, we will enroll additional 8 patients (total of 24 patients). Otherwise, the trial will stop for further evaluation. Due to the limited data currently available in local institutions about a 30 day mortality rate , we will retrospectively evaluate the mortality rate of the ventilated patients without the ULD-WLRT in our institution when data is available.

Time to event secondary objectives (e.g. overall survival, time to discharge) analyses will be performed using Kaplan-Meier survival analysis, with a competing risk model (leaving the study because of death), including effects for demographic/clinical characteristics in the model. Proportional endpoints (such as % patients off ventilator) will be calculated along with the 95% Clopper-Pearson exact confidence interval. Pre/post measurements will be evaluated using linear mixed models for repeated measures (with proper data transformation as needed). Association between demographic/clinical characteristics and other secondary objectives (size of ground glass opacities (GGO)/opacification, for example) will be accomplished with generalized linear models.

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