A WHO COVID-19 research forum in February 2020 recommended evaluation of treatments in large randomized trials, and other WHO expert groups identified 4 re-purposed anti-viral drugs that might have at least a moderate effect on mortality: Remdesivir, Hydroxychloroquine, Lopinavir, and Interferon-β1a. In March 2020, WHO began a large, simple, multi country, open-label randomized trial among hospital inpatients of the effects of these 4 drugs on in-hospital mortality. The trial was adaptive; unpromising drugs could be dropped and others added. Hydroxychloroquine and Lopinavir were eventually dropped, but others, such as monoclonal antibodies, will be added. We report interim mortality results for the original 4 drugs.