Study setting
This meta-trial will include hospitalised patients with COVID-19 pneumonia who do not immediately require invasive mechanical ventilation in participating institutions. A full list of participating institutions will be available in each individual trial record on respective trial registries. Studies from other countries may be added to this meta-trial after publication of the meta-trial protocol, provided the studies meet the criteria for the meta-trial (patient eligibility criteria, intervention, core set of outcome measures).