On May 6, 2020, Sinovac Biotech announced publication of the preclinical study on animals for its vaccine candidate against COVID-19. This was the first challenge study of its SARS-CoV-2 vaccine candidate on animals to prove that the vaccine candidate is safe and provides protection to rhesus macaques. The paper, “Rapid development of an inactivated vaccine for SARS-CoV-2,” iwas published in Science.