In December 2019, a new strain of betacoronavirus, severe acute respiratory syndrome coronavirus 2, which causes coronavirus disease 2019 (COVID-19), emerged in Wuhan, China. Subsequently, the virus quickly spread worldwide and the World Health Organization declared COVID-19 a global pandemic on March 11, 2020. In response to the pandemic, many researchers are working on repurposing existing drugs to alter the course of severe COVID-19, and are testing experimental treatments. Among antiviral agents, remdesivir, an RNA-dependent RNA polymerase inhibitor, showed clinical benefit in a randomized clinical trial. In October 2020, the Food and Drug Administration approved remdesivir for treating hospitalized patients with COVID-19, making it the first drug approved for the disease. The race to produce safe, effective vaccines is also progressing at unprecedented speed, with over 200 under development and 45 candidates already being tested in human clinical trials (as of October 2020). (Korean J Med 2020;95:364-369)