Participants
respiratory or cardiovascular organ support, critically ill, noncritically ill
DISEASE, CRITICALLY ILL, SARS-COV-2 INFECTION
Patients were eligible for the trial if they had laboratory-confirmed SARS-CoV-2 infection and were hospitalized for COVID-19. Confirmation of SARS-CoV-2 positivity was determined by site-specific laboratory standards. The investigators hypothesized that the benefits and risks of a P2Y12 inhibitor varied according to disease severity. As such, the ACTIV-4a design stratified participants as critically ill (requiring intensive care–level support) and noncritically ill (hospitalized but not receiving intensive care–level support) at enrollment. Intensive care–level support was defined by use of respiratory or cardiovascular organ support (oxygen via high-flow nasal cannula ≥20 L/min, noninvasive or invasive mechanical ventilation, vasopressors, inotropes, or extracorporeal membrane oxygenation support).