phase 2a: inclusion criteria: 1. willing and able to provide written informed consent prior to performing study procedures 2. male or female ≥ 18 years and ≤ 85 years 3. hospitalized for covid-19 4. positive sars-cov-2 rt-pcr in any body specimen (nasopharynx, saliva, sputum) ≤ 10 days before enrolment 5. evidence of pulmonary involvement (on lung examination \[rales/crackles\] and/or chest-imaging \[chest x-ray or computed tomography\]) 6. requiring o2 supplement ≤ 6l/min at screening 7. requiring o2 supplementation with spo2 ≥ 94% on o2 therapy at screening 8. first onset of covid-19 symptoms ≤ 10 days, among fever and/or chills, headache, myalgias, cough, shortness of breath, whichever as occurred fist 9. wocbp must have a negative urinary pregnancy test the day of inclusion 10. all sexually active male subjects must agree to use an adequate method of contraception throughout the study period and for 90 days after the last dose of study drug and agree to no sperm donation until the end of the study, or for 90 days after the last dose of xav-19, whichever is longer 11. patients with french social security

phase 2a: inclusion criteria: 1. willing and able to provide written informed consent prior to performing study procedures 2. male or female ≥ 18 years and ≤ 85 years 3. hospitalized for covid-19 4. positive sars-cov-2 rt-pcr in any body specimen (nasopharynx, saliva, sputum) ≤ 10 days before enrolment 5. evidence of pulmonary involvement (on lung examination \[rales/crackles\] and/or chest-imaging \[chest x-ray or computed tomography\]) 6. requiring o2 supplement ≤ 6l/min at screening 7. requiring o2 supplementation with spo2 ≥ 94% on o2 therapy at screening 8. first onset of covid-19 symptoms ≤ 10 days, among fever and/or chills, headache, myalgias, cough, shortness of breath, whichever as occurred fist 9. wocbp must have a negative urinary pregnancy test the day of inclusion 10. all sexually active male subjects must agree to use an adequate method of contraception throughout the study period and for 90 days after the last dose of study drug and agree to no sperm donation until the end of the study, or for 90 days after the last dose of xav-19, whichever is longer 11. patients with french social security

phase 2a: inclusion criteria: willing and able to provide written informed consent prior to performing study procedures male or female ≥ 18 years and ≤ 85 years hospitalized for covid-19 positive sars-cov-2 rt-pcr in any body specimen (nasopharynx, saliva, sputum) ≤ 10 days before enrolment evidence of pulmonary involvement (on lung examination [rales/crackles] and/or chest-imaging [chest x-ray or computed tomography]) requiring o2 supplement ≤ 6l/min at screening requiring o2 supplementation with spo2 ≥ 94% on o2 therapy at screening first onset of covid-19 symptoms ≤ 10 days, among fever and/or chills, headache, myalgias, cough, shortness of breath, whichever as occurred fist wocbp must have a negative urinary pregnancy test the day of inclusion all sexually active male subjects must agree to use an adequate method of contraception throughout the study period and for 90 days after the last dose of study drug and agree to no sperm donation until the end of the study, or for 90 days after the last dose of xav-19, whichever is longer patients with french social security

phase 2a: inclusion criteria: willing and able to provide written informed consent prior to performing study procedures male or female ≥ 18 years and ≤ 85 years hospitalized for covid-19 positive sars-cov-2 rt-pcr in any body specimen (nasopharynx, saliva, sputum) ≤ 10 days before enrolment evidence of pulmonary involvement (on lung examination [rales/crackles] and/or chest-imaging [chest x-ray or computed tomography]) requiring o2 supplement ≤ 6l/min at screening requiring o2 supplementation with spo2 ≥ 94% on o2 therapy at screening first onset of covid-19 symptoms ≤ 10 days, among fever and/or chills, headache, myalgias, cough, shortness of breath, whichever as occurred fist wocbp must have a negative urinary pregnancy test the day of inclusion all sexually active male subjects must agree to use an adequate method of contraception throughout the study period and for 90 days after the last dose of study drug and agree to no sperm donation until the end of the study, or for 90 days after the last dose of xav-19, whichever is longer patients with french social security

phase 2a: inclusion criteria: 1. willing and able to provide written informed consent prior to performing study procedures 2. male or female ≥ 18 years and ≤ 85 years 3. hospitalized for covid-19 4. positive sars-cov-2 rt-pcr in any body specimen (nasopharynx, saliva, sputum) ≤ 10 days before enrolment 5. evidence of pulmonary involvement (on lung examination [rales/crackles] and/or chest-imaging [chest x-ray or computed tomography]) 6. requiring o2 supplement ≤ 6l/min at screening 7. requiring o2 supplementation with spo2 ≥ 94% on o2 therapy at screening 8. first onset of covid-19 symptoms ≤ 10 days, among fever and/or chills, headache, myalgias, cough, shortness of breath, whichever as occurred fist 9. wocbp must have a negative urinary pregnancy test the day of inclusion 10. all sexually active male subjects must agree to use an adequate method of contraception throughout the study period and for 90 days after the last dose of study drug and agree to no sperm donation until the end of the study, or for 90 days after the last dose of xav-19, whichever is longer 11. patients with french social security

phase 2a: inclusion criteria: 1. willing and able to provide written informed consent prior to performing study procedures 2. male or female ≥ 18 years and ≤ 85 years 3. hospitalized for covid-19 4. positive sars-cov-2 rt-pcr in any body specimen (nasopharynx, saliva, sputum) ≤ 10 days before enrolment 5. evidence of pulmonary involvement (on lung examination [rales/crackles] and/or chest-imaging [chest x-ray or computed tomography]) 6. requiring o2 supplement ≤ 6l/min at screening 7. requiring o2 supplementation with spo2 ≥ 94% on o2 therapy at screening 8. first onset of covid-19 symptoms ≤ 10 days, among fever and/or chills, headache, myalgias, cough, shortness of breath, whichever as occurred fist 9. wocbp must have a negative urinary pregnancy test the day of inclusion 10. all sexually active male subjects must agree to use an adequate method of contraception throughout the study period and for 90 days after the last dose of study drug and agree to no sperm donation until the end of the study, or for 90 days after the last dose of xav-19, whichever is longer 11. patients with french social security

inclusion criteria: 1. willing and able to provide written informed consent prior to performing study procedures 2. male or female ≥ 18 years 3. hospitalized for covid-19 4. positive sars-cov-2 rt-pcr in any body specimen (nasopharynx, saliva, sputum) ≤ 10 days before enrolment 5. evidence of pulmonary involvement (on lung examination [rales/crackles] and/or chest-imaging [chest x-ray or computed tomography]) 6. requiring o2 supplement ≤ 6l/min at screening 7. requiring o2 supplementation with spo2 ≥ 94% on o2 therapy at screening 8. first onset of covid-19 symptoms ≤ 10 days, among fever and/or chills, headache, myalgias, cough, shortness of breath, whichever as occurred fist 9. wocbp must have a negative urinary pregnancy test the day of inclusion 10. all sexually active male subjects must agree to use an adequate method of contraception throughout the study period and for 90 days after the last dose of study drug and agree to no sperm donation until the end of the study, or for 90 days after the last dose of xav-19, whichever is longer 11. patients with french social security

inclusion criteria: 1. willing and able to provide written informed consent prior to performing study procedures 2. male or female ≥ 18 years 3. hospitalized for covid-19 4. positive sars-cov-2 rt-pcr in any body specimen (nasopharynx, saliva, sputum) ≤ 10 days before enrolment 5. evidence of pulmonary involvement (on lung examination [rales/crackles] and/or chest-imaging [chest x-ray or computed tomography]) 6. requiring o2 supplement ≤ 6l/min at screening 7. requiring o2 supplementation with spo2 ≥ 94% on o2 therapy at screening 8. first onset of covid-19 symptoms ≤ 10 days, among fever and/or chills, headache, myalgias, cough, shortness of breath, whichever as occurred fist 9. wocbp must have a negative urinary pregnancy test the day of inclusion 10. all sexually active male subjects must agree to use an adequate method of contraception throughout the study period and for 90 days after the last dose of study drug and agree to no sperm donation until the end of the study, or for 90 days after the last dose of xav-19, whichever is longer 11. patients with french social security