Published March 30, 2022 N Engl J Med 2022;386:1721-1731 DOI: 10.1056/NEJMoa2115869 For permission requests, please contact NEJM Reprints at reprints@nejm.org Although vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (Covid-19), have been developed and distributed, major challenges remain regarding vaccine production and allocation.1 The identification of inexpensive, widely available, and effective therapies against...