1. is currently hospitalized. 2. prior history of, or considered to be at risk for, agranulocytosis, nephropathy, liver disease or interstitial pneumonia. 3. current or historic positive human immunodeficiency virus (hiv) test. 4. presence of organ transplant. 5. receipt of cancer chemotherapy or immunomodulatory drugs including but not limited to biologics such as anti-cd20, anti-tnf, anti-il6; alkylating agents (e.g., cyclophosphamide), antimetabolites (e.g., azathioprine), or chronic corticosteroid use equivalent to prednisone \>10 gm/day, during the 2 months prior to screening. 6. confirmed positive for influenza at screening. 7. confirmed positive for respiratory syncytial virus (rsv) at screening. 8. pregnant or breastfeeding. 9. current use of, or known allergy to cysteamine, bucillamine or penicillamine (e.g., for wilson's disease, rheumatoid arthritis). 10. current participation in any other clinical trial of an experimental treatment for any indication including covid-19. 11. receipt of any experimental treatment for covid-19 (herbal, homeopathic, over the counter, off-label, compassionate use, or clinical trial related) within the 30 days prior to screening. 12. receipt of any medication for treatment or prevention of covid-19 being used pursuant to an emergency use authorization (e.g., vaccine) prior to or during study participation

1. is currently hospitalized. 2. prior history of, or considered to be at risk for, agranulocytosis, nephropathy, liver disease or interstitial pneumonia. 3. current or historic positive human immunodeficiency virus (hiv) test. 4. presence of organ transplant. 5. receipt of cancer chemotherapy or immunomodulatory drugs including but not limited to biologics such as anti-cd20, anti-tnf, anti-il6; alkylating agents (e.g., cyclophosphamide), antimetabolites (e.g., azathioprine), or chronic corticosteroid use equivalent to prednisone \>10 gm/day, during the 2 months prior to screening. 6. confirmed positive for influenza at screening. 7. confirmed positive for respiratory syncytial virus (rsv) at screening. 8. pregnant or breastfeeding. 9. current use of, or known allergy to cysteamine, bucillamine or penicillamine (e.g., for wilson's disease, rheumatoid arthritis). 10. current participation in any other clinical trial of an experimental treatment for any indication including covid-19. 11. receipt of any experimental treatment for covid-19 (herbal, homeopathic, over the counter, off-label, compassionate use, or clinical trial related) within the 30 days prior to screening. 12. receipt of any medication for treatment or prevention of covid-19 being used pursuant to an emergency use authorization (e.g., vaccine) prior to or during study participation

is currently hospitalized. prior history of, or considered to be at risk for, agranulocytosis, nephropathy, liver disease or interstitial pneumonia. current or historic positive human immunodeficiency virus (hiv) test. presence of organ transplant. receipt of cancer chemotherapy or immunomodulatory drugs including but not limited to biologics such as anti-cd20, anti-tnf, anti-il6; alkylating agents (e.g., cyclophosphamide), antimetabolites (e.g., azathioprine), or chronic corticosteroid use equivalent to prednisone >10 gm/day, during the 2 months prior to screening. confirmed positive for influenza at screening. confirmed positive for respiratory syncytial virus (rsv) at screening. pregnant or breastfeeding. current use of, or known allergy to cysteamine, bucillamine or penicillamine (e.g., for wilson's disease, rheumatoid arthritis). current participation in any other clinical trial of an experimental treatment for any indication including covid-19. receipt of any experimental treatment for covid-19 (herbal, homeopathic, over the counter, off-label, compassionate use, or clinical trial related) within the 30 days prior to screening. receipt of any medication for treatment or prevention of covid-19 being used pursuant to an emergency use authorization (e.g., vaccine) prior to or during study participation

is currently hospitalized. prior history of, or considered to be at risk for, agranulocytosis, nephropathy, liver disease or interstitial pneumonia. current or historic positive human immunodeficiency virus (hiv) test. presence of organ transplant. receipt of cancer chemotherapy or immunomodulatory drugs including but not limited to biologics such as anti-cd20, anti-tnf, anti-il6; alkylating agents (e.g., cyclophosphamide), antimetabolites (e.g., azathioprine), or chronic corticosteroid use equivalent to prednisone >10 gm/day, during the 2 months prior to screening. confirmed positive for influenza at screening. confirmed positive for respiratory syncytial virus (rsv) at screening. pregnant or breastfeeding. current use of, or known allergy to cysteamine, bucillamine or penicillamine (e.g., for wilson's disease, rheumatoid arthritis). current participation in any other clinical trial of an experimental treatment for any indication including covid-19. receipt of any experimental treatment for covid-19 (herbal, homeopathic, over the counter, off-label, compassionate use, or clinical trial related) within the 30 days prior to screening. receipt of any medication for treatment or prevention of covid-19 being used pursuant to an emergency use authorization (e.g., vaccine) prior to or during study participation