CORIMUNO-19 - Tocilizumab Trial - TOCI (CORIMUNO-TOCI)

Percentage of Participants With WHO Clinical Progression Scale > 5 at Day 4 -- Severe COVID Population (WHO Clinical Progression Scale =5 at Baseline)

Percentage of participants who has died or needed non-invasive or mechanical ventilation by day 4 (WHO clinical progression scale \> 5). A patient with new do-not-resuscitate order at day 4 will be considered as with a score \> 5. WHO progression scale: Uninfected; non viral RNA detected: 0 Asymptomatic; viral RNA detected: 1 Symptomatic; Independent: 2 Symptomatic; Assistance needed: 3 Hospitalized; No oxygen therapy: 4 Hospitalized; oxygen by mask or nasal prongs: 5 Hospitalized; oxygen by NIV or High flow: 6 Intubation and Mechanical ventilation, pO2/FIO2\>=150 OR SpO2/FIO2\>=200: 7 Mechanical ventilation, (pO2/FIO2\<150 OR SpO2/FIO2\<200) OR vasopressors (norepinephrine \>0.3 microg/kg/min): 8 Mechanical ventilation, pO2/FIO2\<150 AND vasopressors (norepinephrine \>0.3 microg/kg/min), OR Dialysis OR ECMO: 9 Dead: 10

Time frame: 4 days

Percentage of Participants With Non-invasive Ventilation, Mechanical Ventilation or Death at Day 14 (WHO Clinical Progression Scale =5 at Baseline)

Survival without needs of ventilator utilization (including non invasive ventilation and high flow) at day 14. Percentage of non-invasive ventilation, mechanical ventilation or death. Thus, events considered are needing ventilator utilization (mechanical or non-invasive ventilation including high flow oxygen), or death. New do-not-resuscitate (DNR) order (if given after the inclusion of the patient) will be considered as an event at the date of the DNR.

Time frame: Day 1 to Day 14

Percentage of Participants With no Improvement in WHO Clinical Progression Scale at Day 4 -- Critical COVID Population ( WHO Clinical Progression Scale >5 at Baseline)

Results are presented as the percentage not improved, so that an effective treatment would be associated with a decrease in percentage WHO progression scale: Uninfected; non viral RNA detected: 0 Asymptomatic; viral RNA detected: 1 Symptomatic; Independent: 2 Symptomatic; Assistance needed: 3 Hospitalized; No oxygen therapy: 4 Hospitalized; oxygen by mask or nasal prongs: 5 Hospitalized; oxygen by NIV or High flow: 6 Intubation and Mechanical ventilation, pO2/FIO2\>=150 OR SpO2/FIO2\>=200: 7 Mechanical ventilation, (pO2/FIO2\<150 OR SpO2/FIO2\<200) OR vasopressors (norepinephrine \>0.3 microg/kg/min): 8 Mechanical ventilation, pO2/FIO2\<150 AND vasopressors (norepinephrine \>0.3 microg/kg/min), OR Dialysis OR ECMO: 9 Dead: 10

Time frame: 4 days

Cumulative Incidence (Percentage of Participants) With Successful Tracheal Extubation at Day 14 -- Critical COVID Population (WHO Clinical Progression Scale >5 at Baseline)

Cumulative incidence of successful tracheal extubation (defined as duration extubation \> 48h) at day 14 if patients have been intubated before day 14 ; or removal of Non Invasive Ventilation or high flow (for \> 48h) if they were included under oxygen by Non Invasive Ventilation or High flow (score 6) and remained without intubation. Death or new do-not-resuscitate order (if given after the inclusion of the patient) will be considered as a competing event.

Time frame: Day 1 to Day 14