Effectiveness of Hydroxychloroquine in COVID-19 disease: A done and dusted situation?

A total of 539 COVID-19 hospitalized patients were included in our cohort in Milan, from February 24 to May 17, 2020, of whom 174 died in hospital (day 14 probability of death: 29.5% -95%CI: 25.5-34.0). We divided a subset of our cohort into three groups who started treatment a median of 1 day after admission: those receiving hydroxychloroquine alone (N = 197), those receiving hydroxycholoroquine + azithromycin (N = 94), and those receiving neither (controls) (N = 92). Of the latter group, ten started HIV antivirals (boosted-lopinavir or -darunavir), one teicoplanin, twelve immunomodulatory drugs, or corticosteroids, 23 heparin and 46 remained untreated. The percent of death in the three groups was 27%, 23%, and 51%. Mechanical ventilation was used in 4.3% of hydroxychloroquine, 14.2% of hydroxychloroquine + azithromycin, and 26.1% of controls. Unweighted and weighted relative hazards of mortality are shown in Table 1 . After adjusting * Adjusted for age, gender, number of comorbidities, CVD (yes/no), duration of symptoms, date of admission, CRP and censoring using IPW. £ The overall estimate was also adjusted for baseline COVID-19 disease severity. # Heparin, immuno-modulatory drugs, HIV antivirals, combinations of these or no drugs at all. & 45 patients missing baseline PO2/FiO2 not included in the stratified analysis.