Outcomes

The primary outcome was the proportion of participants with hospital admission or death from any cause within 28 days from randomisation.

Secondary outcomes were the proportion of participants with hospital admission with respiratory failure requiring non-invasive mechanical ventilation or invasive mechanical ventilation or death from any cause within 28 days from randomisation; the proportion of participants with hospital admission with respiratory failure requiring invasive or non-invasive mechanical ventilation support or death from any cause over 28 days from randomisation among those with a PCR-confirmed diagnosis of COVID-19 at randomisation; mortality or all-cause hospital admission amongst those with a PCR-confirmed diagnosis; all-cause mortality at day 28; the proportion progressing to clinician-diagnosed pneumonia; the proportion progressing to severe pneumonia; and differences in the peak severity of respiratory illness according to a nine-level ordinal severity score for clinical condition (appendix p 116). We also assessed safety and tolerability of azithromycin based on serious adverse events.