A prospective study of HCQ on COVID-19 patients (13 cases) admitted to the ICU in France showed that the first daily dose of 800 mg/1 time for 1 day, and 200 mg/2 times/day for 7 days was recommended to maintain the HCQ treatment level (1–2 mg/l) based on physiologically pharmacokinetic (PBPK) models for COVID-19 patients in ICU [67].