Sargramostim Use in COVID-19 to Recover Patient Health

Inclusion Criteria: 1. Patients with a positive laboratory diagnosis of SARS-CoV-2 infection by an antigen or a molecular test ≤5 days prior to randomization. The test should have been authorized by the relevant regulatory authority. 2. Have one or more of the following mild or moderate COVID-19 symptoms for ≤5 days prior to randomization: 1. Fever or chills 2. New onset or worsening cough 3. Sore throat 4. Malaise or fatigue 5. Headache 6. Muscle pain (myalgias) or body aches 7. Gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea) 8. New onset or worsening shortness of breath or difficulty breathing 9. Nasal congestion or runny nose 10. New loss of taste (ageusia) and/or smell (anosmia). Note: any of these symptoms (ageusia, anosmia) alone or in combination cannot be used as the SOLE qualifying symptoms for enrollment. 3. At higher risk for progression to more severe COVID-19 1. Age ≥ 60 years 2. Age 18-59 years with a clinically stable medical history of at least 1 or more of the following conditions that could lead to severe COVID-19: * Chronic respiratory conditions such as asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis * Obesity with BMI ≥ 30 kg/m2 * Cardiovascular disease * Sickle cell disease or thalassemia * Diabetes mellitus being managed with concomitant medications * Hypertension being managed with concomitant medications * Chronic kidney disease 4. Oxygen saturation by pulse oximeter \> 93% on room air. Note: at altitudes of \>4000 feet above sea level, oxygen saturation by pulse oximeter \> 91% on room air is permitted 5. Negative pregnancy test (if woman of childbearing potential) 6. Females of childbearing potential and males with female partners of childbearing potential must agree to use acceptable contraceptive methods from screening to Day 28 7. The patient (or legally authorized decision maker) must give informed consent Exclusion Criteria: 1. Hospitalized patients 2. Patients who have received or are receiving other treatments that are not approved/authorized by the relevant regulatory authority for the treatment of patients with mild or moderate COVID-19 in an outpatient setting 3. Patients enrolled in interventional clinical trials for other experimental therapies 4. Patients on chronic oxygen supplementation due to cardiopulmonary or other conditions 5. Patients with unstable comorbid conditions (e.g., decompensated congestive heart failure, COPD with exacerbation, current angina pectoris, uncontrolled diabetes mellitus, uncontrolled hypertension, uncontrolled asthma) 6. Patients with severe pulmonary comorbid conditions, including systemic steroid-dependent asthma, systemic steroid-dependent COPD, oxygen-dependent COPD, lung transplant, or cystic fibrosis 7. Patients who have received highly immunosuppressive therapy (to include systemic corticosteroids) or anti-cancer combination chemotherapy within 24 hours prior to first dose of study drug 8. Patients with known or suspected intolerance or hypersensitivity to sargramostim, or any component of the product 9. Patients who have previously experienced severe and unexplained side effects during aerosol delivery of any kind of medical product 10. Pregnant or breastfeeding females 11. Patients who, in the opinion of the Investigator, will not be able to comply with all the study procedures and visits as outlined in the schedule of events, including follow-up