inclusion criteria : - participants with diagnosis of covid-19 via an approved or authorized molecular test - presence of symptoms compatible with covid-19 at the time of screening - time between onset of symptoms and first dose of hydroxychloroquine or placebo is 96 hours or less - female participants must use an acceptable birth control method, as specified by each site and country

inclusion criteria : - participants with diagnosis of covid-19 via an approved or authorized molecular test - presence of symptoms compatible with covid-19 at the time of screening - time between onset of symptoms and first dose of hydroxychloroquine or placebo is 96 hours or less - female participants must use an acceptable birth control method, as specified by each site and country