To the Editor—Jeremy Farrar, Director of Wellcome and Chair of the World Health Organization R&D Blueprint Scientific Advisory Group, has said “It’s critical that the global research effort is rapid, robust and is conducted at scale and co-ordinated across multiple countries.” Of the> 2,000 planned drug studies examining COVID-19 treatments (https://www. covid-trials. org), most have delivered little or no directly useful information1. Exceptions include two large, adaptive, pragmatic trials, RECOVERY and SOLIDARITY, which combined have randomized> 20,000 patients to assess the effects of several treatments on mortality2, and the US National Institutes of Health ACTT trial, which randomized 1,059 patients to assess the effect of remdesivir on time to disease resolution3. The speed of the RECOVERY trial (https://www. recoverytrial. net/files/recovery-protocol-v7-0-2020-06-18. pdf) was record-breaking: the period from protocol to first patient recruitment was nine days, with the 176 UK hospitals recruiting> 12,000 hospitalized patients (15% UK COVID-19 cases), and it provided clear answers within a few months on the effectiveness of dexamethasone2 and the ineffectiveness of hydroxychloroquine and lopinavir–ritonavir (Fig. 1). Notably, it sought to achieve reliability and quality by design rather than by compliance with good clinical practice or site monitors, relying instead on centralized computer checks on site behavior and patient compliance, and utilizing central National Health Service medical records of treatment and outcome. Also, it did not necessarily require written consent where the medical emergency rendered this inappropriate. The World Health Organization–led SOLIDARITY trial (https://www. who. int/emergencies/diseases/novel-coronavirus-2019/global-research-on-novel-coronavirus-2019-ncov/solidarity-clinical-trial-for-covid-19-treatments) has recruited> 9,000 patients across 30 countries and is currently recruiting about 2,000 patients a month. SOLIDARITY has also provided important evidence on the ineffectiveness of hydroxychloroquine and lopinavir–ritonavir and is the largest trial examining the effects of remdesivir and interferon on survival. SOLIDARITY also includes add-on sub-studies (Nordic and Canadian arms and the European DisCoVeRy trial; https://presse. inserm. fr/en/launch-of-a-europeanclinical-trial-against-covid-19/38737/) that provide more-detailed data on safety and clinical and laboratory surrogates. Both trials have common origins in the international collaborative work enabled by the World Health Organization R&D Blueprint (Fig. 1). The RECOVERY protocol, written in only two days, was heavily influenced by the 1980s ideas of large, simple, pragmatic trials4, exemplified by the International Studies of Infarct Survival5: broad, simple inclusion criteria; central randomization; no additional biological samples or extraneous data collection; and the simple, unambiguous primary outcome of all-cause mortality. RECOVERY benefited from the willingness of UK doctors to randomize unproven treatments (rather than, as in many other countries, obstructing randomization by incorporating unproven drugs into local practices and guidelines); strong national support from funders and the National Health Service; and the pre-existing UK clinical-trials network, which provided research nurses at recruiting centers6. RECOVERY’s streamlined trial conduct and data collection7—including foregoing