1. Have an oxygen saturation of <90% while breathing ambient air. <br/ > 2. Any physical examination findings and/or history of any illness that, in the opinion of the study investigator, might confound the results of the study or pose an additional risk to the subject. <br/ > 3. Nursing women or women of childbearing potential (WOCBP) with a positive pregnancy test. <br/ > 4. Treatment with another DHODH inhibitor (e.g., leflunomide, teriflunomide) or other agents known to cause bone marrow suppression leading to thrombocytopenia. <br/ > 5. Ongoing treatment with aspirin and or dipyridamole, famotidine or cimetidine. Remdesivir and ivermectin are prohibited through Study Day 8. Steroids are permitted per the guidelines. <br/ > 6. Platelets less than or equal to 125,000 cell/mm3. <br/ > 7. Hemoglobin less than 10 gm/dL. <br/ > 8. Absolute neutrophil count less than 1000 cells/mm3. <br/ > 9. Renal dysfunction, i.e., creatinine clearance less than 30 mL/min. <br/ > 10. AST or ALT more than 3 x ULN, or total bilirubin more than ULN. Gilbertâ??s Syndrome is allowed. <br/ > 11. Bleeding disorders or blood loss requiring transfusion in the six weeks preceding enrollment. <br/ > 12. Ongoing gastrointestinal ulcer, or gastrointestinal bleeding within 6 weeks of first dose. <br/ > 13. Chronic hepatitis B infection, active hepatitis C infection, active liver disease and/or cirrhosis per subject report. <br/ > 14. Heart failure, current uncontrolled cardiovascular disease, including unstable angina, uncontrolled arrhythmias, major adverse cardiac event within 6 months (e.g., stroke, myocardial infarction, hospitalization due to heart failure, or revascularization procedure). <br/ >

1. Have an oxygen saturation of <90% while breathing ambient air. <br/ > 2. Any physical examination findings and/or history of any illness that, in the opinion of the study investigator, might confound the results of the study or pose an additional risk to the subject. <br/ > 3. Nursing women or women of childbearing potential (WOCBP) with a positive pregnancy test. <br/ > 4. Treatment with another DHODH inhibitor (e.g., leflunomide, teriflunomide) or other agents known to cause bone marrow suppression leading to thrombocytopenia. <br/ > 5. Ongoing treatment with aspirin and or dipyridamole, famotidine or cimetidine. Remdesivir and ivermectin are prohibited through Study Day 8. Steroids are permitted per the guidelines. <br/ > 6. Platelets less than or equal to 125,000 cell/mm3. <br/ > 7. Hemoglobin less than 10 gm/dL. <br/ > 8. Absolute neutrophil count less than 1000 cells/mm3. <br/ > 9. Renal dysfunction, i.e., creatinine clearance less than 30 mL/min. <br/ > 10. AST or ALT more than 3 x ULN, or total bilirubin more than ULN. Gilbertâ??s Syndrome is allowed. <br/ > 11. Bleeding disorders or blood loss requiring transfusion in the six weeks preceding enrollment. <br/ > 12. Ongoing gastrointestinal ulcer, or gastrointestinal bleeding within 6 weeks of first dose. <br/ > 13. Chronic hepatitis B infection, active hepatitis C infection, active liver disease and/or cirrhosis per subject report. <br/ > 14. Heart failure, current uncontrolled cardiovascular disease, including unstable angina, uncontrolled arrhythmias, major adverse cardiac event within 6 months (e.g., stroke, myocardial infarction, hospitalization due to heart failure, or revascularization procedure). <br/ >