1. any co-morbidity that may add risk to the treatment in the judgment of the investigator, particularly patients with known cardiac conditions, and serious neuropsychiatric conditions such as psychosis or major depression 2. requiring intubation and mechanical ventilation at baseline 3. patient has a 'do not intubate' and/or 'do not resuscitate' order in place 4. oxygen saturation \>95% on room air 5. any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization 6. patient is, in the investigator's clinical judgement, unlikely to survive \>72 hours 7. pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . 8. unwillingness or inability to comply with procedures required in this protocol. 9. corrected qt (qtc) interval on electrocardiogram (ecg) \>470 ms for females or \>450 ms for males, calculated using friedericia's formula (qtcf) 10. ast (sgot) or alt (sgpt) \> 2.0 x upper limit of normal (uln) 11. total bilirubin \>1.5x uln (except where bilirubin increase is due to gilbert's syndrome) 12. serum creatinine \>2.0 x uln 13. absolute neutrophil count \<1000 cells/mm3 14. platelet count \<75,000/mm3 15. hemoglobin \<8.0 g/dl 16. medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1 should be avoided with opaganib 17. moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2 are prohibited 18. currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism 19. current drug or alcohol abuse 20. currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies 21. treatment with any medication that causes qt prolongation within seven days, or 5 half-lives, whichever is longest, prior to initiation of study drug, or intention to use them throughout the study, including but not limited to: amiodarone, amitriptyline, citalopram dose greater than 20 mg/day, dihydroergotamine, disopyramide, dofetilide, dronedarone, ergotamine, ibutilde, ondansetron or other 5-ht3 receptor antagonists, pimozide, procainamide, quinidine, quinine, quinolone, ranolazine, risperidone, sotaloland tolteridine. investigators are directed to the following up-to-date web site listing qt prolonging drugs: https://www.crediblemeds.org/index.php/drugsearch

1. any co-morbidity that may add risk to the treatment in the judgment of the investigator, particularly patients with known cardiac conditions, and serious neuropsychiatric conditions such as psychosis or major depression 2. requiring intubation and mechanical ventilation at baseline 3. patient has a 'do not intubate' and/or 'do not resuscitate' order in place 4. oxygen saturation \>95% on room air 5. any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization 6. patient is, in the investigator's clinical judgement, unlikely to survive \>72 hours 7. pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . 8. unwillingness or inability to comply with procedures required in this protocol. 9. corrected qt (qtc) interval on electrocardiogram (ecg) \>470 ms for females or \>450 ms for males, calculated using friedericia's formula (qtcf) 10. ast (sgot) or alt (sgpt) \> 2.0 x upper limit of normal (uln) 11. total bilirubin \>1.5x uln (except where bilirubin increase is due to gilbert's syndrome) 12. serum creatinine \>2.0 x uln 13. absolute neutrophil count \<1000 cells/mm3 14. platelet count \<75,000/mm3 15. hemoglobin \<8.0 g/dl 16. medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1 should be avoided with opaganib 17. moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2 are prohibited 18. currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism 19. current drug or alcohol abuse 20. currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies 21. treatment with any medication that causes qt prolongation within seven days, or 5 half-lives, whichever is longest, prior to initiation of study drug, or intention to use them throughout the study, including but not limited to: amiodarone, amitriptyline, citalopram dose greater than 20 mg/day, dihydroergotamine, disopyramide, dofetilide, dronedarone, ergotamine, ibutilde, ondansetron or other 5-ht3 receptor antagonists, pimozide, procainamide, quinidine, quinine, quinolone, ranolazine, risperidone, sotaloland tolteridine. investigators are directed to the following up-to-date web site listing qt prolonging drugs: https://www.crediblemeds.org/index.php/drugsearch

any co-morbidity that may add risk to the treatment in the judgment of the investigator, particularly patients with known cardiac conditions, and serious neuropsychiatric conditions such as psychosis or major depression requiring intubation and mechanical ventilation at baseline patient has a 'do not intubate' and/or 'do not resuscitate' order in place oxygen saturation >95% on room air any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization patient is, in the investigator's clinical judgement, unlikely to survive >72 hours pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . unwillingness or inability to comply with procedures required in this protocol. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) ast (sgot) or alt (sgpt) > 2.0 x upper limit of normal (uln) total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) serum creatinine >2.0 x uln absolute neutrophil count <1000 cells/mm3 platelet count <75,000/mm3 hemoglobin <8.0 g/dl medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1 should be avoided with opaganib moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2 are prohibited currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism current drug or alcohol abuse currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies treatment with any medication that causes qt prolongation within seven days, or 5 half-lives, whichever is longest, prior to initiation of study drug, or intention to use them throughout the study, including but not limited to: amiodarone, amitriptyline, citalopram dose greater than 20 mg/day, dihydroergotamine, disopyramide, dofetilide, dronedarone, ergotamine, ibutilde, ondansetron or other 5-ht3 receptor antagonists, pimozide, procainamide, quinidine, quinine, quinolone, ranolazine, risperidone, sotaloland tolteridine. investigators are directed to the following up-to-date web site listing qt prolonging drugs: https://www.crediblemeds.org/index.php/drugsearch

any co-morbidity that may add risk to the treatment in the judgment of the investigator, particularly patients with known cardiac conditions, and serious neuropsychiatric conditions such as psychosis or major depression requiring intubation and mechanical ventilation at baseline patient has a 'do not intubate' and/or 'do not resuscitate' order in place oxygen saturation >95% on room air any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization patient is, in the investigator's clinical judgement, unlikely to survive >72 hours pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . unwillingness or inability to comply with procedures required in this protocol. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) ast (sgot) or alt (sgpt) > 2.0 x upper limit of normal (uln) total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) serum creatinine >2.0 x uln absolute neutrophil count <1000 cells/mm3 platelet count <75,000/mm3 hemoglobin <8.0 g/dl medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1 should be avoided with opaganib moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2 are prohibited currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism current drug or alcohol abuse currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies treatment with any medication that causes qt prolongation within seven days, or 5 half-lives, whichever is longest, prior to initiation of study drug, or intention to use them throughout the study, including but not limited to: amiodarone, amitriptyline, citalopram dose greater than 20 mg/day, dihydroergotamine, disopyramide, dofetilide, dronedarone, ergotamine, ibutilde, ondansetron or other 5-ht3 receptor antagonists, pimozide, procainamide, quinidine, quinine, quinolone, ranolazine, risperidone, sotaloland tolteridine. investigators are directed to the following up-to-date web site listing qt prolonging drugs: https://www.crediblemeds.org/index.php/drugsearch

1. any co-morbidity that may add risk to the treatment in the judgment of the investigator, particularly patients with known cardiac conditions, and serious neuropsychiatric conditions such as psychosis or major depression 2. requiring intubation and mechanical ventilation at baseline 3. patient has a 'do not intubate' and/or 'do not resuscitate' order in place 4. oxygen saturation >95% on room air 5. any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization 6. patient is, in the investigator's clinical judgement, unlikely to survive >72 hours 7. pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . 8. unwillingness or inability to comply with procedures required in this protocol. 9. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) 10. ast (sgot) or alt (sgpt) > 2.0 x upper limit of normal (uln) 11. total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) 12. serum creatinine >2.0 x uln 13. absolute neutrophil count <1000 cells/mm3 14. platelet count <75,000/mm3 15. hemoglobin <8.0 g/dl 16. medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1 should be avoided with opaganib 17. moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2 are prohibited 18. currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism 19. current drug or alcohol abuse 20. currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies 21. treatment with any medication that causes qt prolongation within seven days, or 5 half-lives, whichever is longest, prior to initiation of study drug, or intention to use them throughout the study, including but not limited to: amiodarone, amitriptyline, citalopram dose greater than 20 mg/day, dihydroergotamine, disopyramide, dofetilide, dronedarone, ergotamine, ibutilde, ondansetron or other 5-ht3 receptor antagonists, pimozide, procainamide, quinidine, quinine, quinolone, ranolazine, risperidone, sotaloland tolteridine. investigators are directed to the following up-to-date web site listing qt prolonging drugs: https://www.crediblemeds.org/index.php/drugsearch

1. any co-morbidity that may add risk to the treatment in the judgment of the investigator, particularly patients with known cardiac conditions, and serious neuropsychiatric conditions such as psychosis or major depression 2. requiring intubation and mechanical ventilation at baseline 3. patient has a 'do not intubate' and/or 'do not resuscitate' order in place 4. oxygen saturation >95% on room air 5. any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization 6. patient is, in the investigator's clinical judgement, unlikely to survive >72 hours 7. pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . 8. unwillingness or inability to comply with procedures required in this protocol. 9. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) 10. ast (sgot) or alt (sgpt) > 2.0 x upper limit of normal (uln) 11. total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) 12. serum creatinine >2.0 x uln 13. absolute neutrophil count <1000 cells/mm3 14. platelet count <75,000/mm3 15. hemoglobin <8.0 g/dl 16. medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1 should be avoided with opaganib 17. moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2 are prohibited 18. currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism 19. current drug or alcohol abuse 20. currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies 21. treatment with any medication that causes qt prolongation within seven days, or 5 half-lives, whichever is longest, prior to initiation of study drug, or intention to use them throughout the study, including but not limited to: amiodarone, amitriptyline, citalopram dose greater than 20 mg/day, dihydroergotamine, disopyramide, dofetilide, dronedarone, ergotamine, ibutilde, ondansetron or other 5-ht3 receptor antagonists, pimozide, procainamide, quinidine, quinine, quinolone, ranolazine, risperidone, sotaloland tolteridine. investigators are directed to the following up-to-date web site listing qt prolonging drugs: https://www.crediblemeds.org/index.php/drugsearch

any co-morbidity that may add risk to the treatment in the judgment of the investigator, particularly patients with known cardiac conditions, and serious neuropsychiatric conditions such as psychosis or major depression requiring intubation and mechanical ventilation at baseline patient has a 'do not intubate' and/or 'do not resuscitate' order in place oxygen saturation >95% on room air any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization patient is, in the investigator's clinical judgement, unlikely to survive >72 hours pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . unwillingness or inability to comply with procedures required in this protocol. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) ast (sgot) or alt (sgpt) > 2.0 x upper limit of normal (uln) total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) serum creatinine >2.0 x uln absolute neutrophil count <1000 cells/mm3 platelet count <75,000/mm3 hemoglobin <8.0 g/dl medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1 should be avoided with opaganib moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2 are prohibited currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism current drug or alcohol abuse currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies treatment with any medication that causes qt prolongation within seven days, or 5 half-lives, whichever is longest, prior to initiation of study drug, or intention to use them throughout the study, including but not limited to: amiodarone, amitriptyline, citalopram dose greater than 20 mg/day, dihydroergotamine, disopyramide, dofetilide, dronedarone, ergotamine, ibutilde, ondansetron or other 5-ht3 receptor antagonists, pimozide, procainamide, quinidine, quinine, quinolone, ranolazine, risperidone, sotaloland tolteridine. investigators are directed to the following up-to-date web site listing qt prolonging drugs: https://www.crediblemeds.org/index.php/drugsearch

any co-morbidity that may add risk to the treatment in the judgment of the investigator, particularly patients with known cardiac conditions, and serious neuropsychiatric conditions such as psychosis or major depression requiring intubation and mechanical ventilation at baseline patient has a 'do not intubate' and/or 'do not resuscitate' order in place oxygen saturation >95% on room air any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization patient is, in the investigator's clinical judgement, unlikely to survive >72 hours pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . unwillingness or inability to comply with procedures required in this protocol. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) ast (sgot) or alt (sgpt) > 2.0 x upper limit of normal (uln) total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) serum creatinine >2.0 x uln absolute neutrophil count <1000 cells/mm3 platelet count <75,000/mm3 hemoglobin <8.0 g/dl medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1 should be avoided with opaganib moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2 are prohibited currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism current drug or alcohol abuse currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies treatment with any medication that causes qt prolongation within seven days, or 5 half-lives, whichever is longest, prior to initiation of study drug, or intention to use them throughout the study, including but not limited to: amiodarone, amitriptyline, citalopram dose greater than 20 mg/day, dihydroergotamine, disopyramide, dofetilide, dronedarone, ergotamine, ibutilde, ondansetron or other 5-ht3 receptor antagonists, pimozide, procainamide, quinidine, quinine, quinolone, ranolazine, risperidone, sotaloland tolteridine. investigators are directed to the following up-to-date web site listing qt prolonging drugs: https://www.crediblemeds.org/index.php/drugsearch

1. any co-morbidity that may add risk to the treatment in the judgment of the investigator, particularly patients with known cardiac conditions, and serious neuropsychiatric conditions such as psychosis or major depression 2. requiring intubation and mechanical ventilation at baseline 3. patient has a 'do not intubate' and/or 'do not resuscitate' order in place 4. oxygen saturation >95% on room air 5. any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization 6. patient is, in the investigator's clinical judgement, unlikely to survive >72 hours 7. pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . 8. unwillingness or inability to comply with procedures required in this protocol. 9. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) 10. ast (sgot) or alt (sgpt) > 2.0 x upper limit of normal (uln) 11. total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) 12. serum creatinine >2.0 x uln 13. absolute neutrophil count <1000 cells/mm3 14. platelet count <75,000/mm3 15. hemoglobin <8.0 g/dl 16. medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1 should be avoided with opaganib 17. moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2 are prohibited 18. currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism 19. current drug or alcohol abuse 20. currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies 21. treatment with any medication that causes qt prolongation within seven days, or 5 half-lives, whichever is longest, prior to initiation of study drug, or intention to use them throughout the study, including but not limited to: amiodarone, amitriptyline, citalopram dose greater than 20 mg/day, dihydroergotamine, disopyramide, dofetilide, dronedarone, ergotamine, ibutilde, ondansetron or other 5-ht3 receptor antagonists, pimozide, procainamide, quinidine, quinine, quinolone, ranolazine, risperidone, sotaloland tolteridine. investigators are directed to the following up-to-date web site listing qt prolonging drugs: https://www.crediblemeds.org/index.php/drugsearch

1. any co-morbidity that may add risk to the treatment in the judgment of the investigator, particularly patients with known cardiac conditions, and serious neuropsychiatric conditions such as psychosis or major depression 2. requiring intubation and mechanical ventilation at baseline 3. patient has a 'do not intubate' and/or 'do not resuscitate' order in place 4. oxygen saturation >95% on room air 5. any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization 6. patient is, in the investigator's clinical judgement, unlikely to survive >72 hours 7. pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . 8. unwillingness or inability to comply with procedures required in this protocol. 9. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) 10. ast (sgot) or alt (sgpt) > 2.0 x upper limit of normal (uln) 11. total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) 12. serum creatinine >2.0 x uln 13. absolute neutrophil count <1000 cells/mm3 14. platelet count <75,000/mm3 15. hemoglobin <8.0 g/dl 16. medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1 should be avoided with opaganib 17. moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2 are prohibited 18. currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism 19. current drug or alcohol abuse 20. currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies 21. treatment with any medication that causes qt prolongation within seven days, or 5 half-lives, whichever is longest, prior to initiation of study drug, or intention to use them throughout the study, including but not limited to: amiodarone, amitriptyline, citalopram dose greater than 20 mg/day, dihydroergotamine, disopyramide, dofetilide, dronedarone, ergotamine, ibutilde, ondansetron or other 5-ht3 receptor antagonists, pimozide, procainamide, quinidine, quinine, quinolone, ranolazine, risperidone, sotaloland tolteridine. investigators are directed to the following up-to-date web site listing qt prolonging drugs: https://www.crediblemeds.org/index.php/drugsearch

1. any co-morbidity that may add risk to the treatment in the judgement of the investigator. 2. requiring intubation and mechanical ventilation at baseline 3. patient has a 'do not intubate' and/or 'do not resuscitate' order in place 4. oxygen saturation >95% on room air 5. any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization 6. patient is, in the investigator's clinical judgement, unlikely to survive >72 hours 7. pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . 8. unwillingness or inability to comply with procedures required in this protocol. 9. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) 10. ast (sgot) or alt (sgpt) > 5.0 x upper limit of normal (uln) 11. total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) 12. serum creatinine >2.0 x uln 13. absolute neutrophil count <1000 cells/mm3 14. platelet count <75,000/mm3 15. hemoglobin <8.0 g/dl 16. medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1. these should be decided in discussion with the medical monitor on a case-by-case basis. 17. moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2. these should be decided in discussion with the medical monitor on a case-by-case basis. 18. currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism 19. current drug or alcohol abuse 20. currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies

1. any co-morbidity that may add risk to the treatment in the judgement of the investigator. 2. requiring intubation and mechanical ventilation at baseline 3. patient has a 'do not intubate' and/or 'do not resuscitate' order in place 4. oxygen saturation >95% on room air 5. any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization 6. patient is, in the investigator's clinical judgement, unlikely to survive >72 hours 7. pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . 8. unwillingness or inability to comply with procedures required in this protocol. 9. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) 10. ast (sgot) or alt (sgpt) > 5.0 x upper limit of normal (uln) 11. total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) 12. serum creatinine >2.0 x uln 13. absolute neutrophil count <1000 cells/mm3 14. platelet count <75,000/mm3 15. hemoglobin <8.0 g/dl 16. medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1. these should be decided in discussion with the medical monitor on a case-by-case basis. 17. moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2. these should be decided in discussion with the medical monitor on a case-by-case basis. 18. currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism 19. current drug or alcohol abuse 20. currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies

1. any co-morbidity that may add risk to the treatment in the judgement of the investigator. 2. requiring intubation and mechanical ventilation at baseline 3. patient has a 'do not intubate' and/or 'do not resuscitate' order in place 4. oxygen saturation >95% on room air 5. any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization 6. patient is, in the investigator's clinical judgement, unlikely to survive >72 hours 7. pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . 8. unwillingness or inability to comply with procedures required in this protocol. 9. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) 10. ast (sgot) or alt (sgpt) > 2.5 x upper limit of normal (uln) 11. total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) 12. serum creatinine >2.0 x uln 13. absolute neutrophil count <1000 cells/mm3 14. platelet count <75,000/mm3 15. hemoglobin <8.0 g/dl 16. medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1. these should be decided in discussion with the medical monitor on a case-by-case basis. 17. moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2. these should be decided in discussion with the medical monitor on a case-by-case basis. 18. currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism 19. current drug or alcohol abuse 20. currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies

1. any co-morbidity that may add risk to the treatment in the judgement of the investigator. 2. requiring intubation and mechanical ventilation at baseline 3. patient has a 'do not intubate' and/or 'do not resuscitate' order in place 4. oxygen saturation >95% on room air 5. any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization 6. patient is, in the investigator's clinical judgement, unlikely to survive >72 hours 7. pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . 8. unwillingness or inability to comply with procedures required in this protocol. 9. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) 10. ast (sgot) or alt (sgpt) > 2.5 x upper limit of normal (uln) 11. total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) 12. serum creatinine >2.0 x uln 13. absolute neutrophil count <1000 cells/mm3 14. platelet count <75,000/mm3 15. hemoglobin <8.0 g/dl 16. medications that are sensitive substrates, or substrates with a narrow therapeutic range, for cyp1a2, cyp2b6, cyp2c8, cyp2c9, cyp2c19 cyp2d6 , cyp3a4, p-gp, bcrp and oatp1b1. these should be decided in discussion with the medical monitor on a case-by-case basis. 17. moderate or strong inhibitors of cyp1a2, cyp3a4, cyp2d6 or p-gp or moderate to strong inducers of cyp3a4 and cyp1a2. these should be decided in discussion with the medical monitor on a case-by-case basis. 18. currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism 19. current drug or alcohol abuse 20. currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies

1. any co-morbidity that may add risk to the treatment in the judgement of the investigator. 2. requiring intubation and mechanical ventilation 3. oxygen saturation >95% on room air 4. any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization 5. patient is, in the investigator's clinical judgement, unlikely to survive >72 hours 6. pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . 7. unwillingness or inability to comply with procedures required in this protocol. 8. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) 9. ast (sgot) or alt (sgpt) > 2.5 x upper limit of normal (uln) 10. total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) 11. serum creatinine >2.0 x uln 12. absolute neutrophil count <1000 cells/mm3 13. platelet count <75,000/mm3 14. hemoglobin <8.0 g/dl 15. currently taking medications that are sensitive cyp3a4, cyp2c9 or cyp2c19 substrates and have a narrow therapeutic index 16. currently taking medications that are strong inducers or inhibitors of cyp2d6 and cyp3a4 17. currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism 18. current drug or alcohol abuse 19. currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies

1. any co-morbidity that may add risk to the treatment in the judgement of the investigator. 2. requiring intubation and mechanical ventilation 3. oxygen saturation >95% on room air 4. any preexisting respiratory condition that requires intermittent or continuous ambulatory oxygen prior to hospitalization 5. patient is, in the investigator's clinical judgement, unlikely to survive >72 hours 6. pregnant (positive serum or urine test within 3 days prior to randomization) or nursing women . 7. unwillingness or inability to comply with procedures required in this protocol. 8. corrected qt (qtc) interval on electrocardiogram (ecg) >470 ms for females or >450 ms for males, calculated using friedericia's formula (qtcf) 9. ast (sgot) or alt (sgpt) > 2.5 x upper limit of normal (uln) 10. total bilirubin >1.5x uln (except where bilirubin increase is due to gilbert's syndrome) 11. serum creatinine >2.0 x uln 12. absolute neutrophil count <1000 cells/mm3 13. platelet count <75,000/mm3 14. hemoglobin <8.0 g/dl 15. currently taking medications that are sensitive cyp3a4, cyp2c9 or cyp2c19 substrates and have a narrow therapeutic index 16. currently taking medications that are strong inducers or inhibitors of cyp2d6 and cyp3a4 17. currently taking warfarin, apixaban, argatroban or rivaroxaban due to drug-drug interaction based on cyp450 metabolism 18. current drug or alcohol abuse 19. currently participating in a clinical study assessing pharmacological treatments, including anti-viral studies