Following the publication of the genetic sequence of SARS-CoV-2 on January 11, 2020, intense research efforts have been devoted to developing a vaccine against COVID-19. With unprecedented speed, this extraordinary scientific mobilization led the first vaccine candidate to enter the Phase I human clinical trial on March 16, 2020, and other novel candidates are rapidly following.59 Up to May 22, 2020, there are 10 COVID-19 candidate vaccines in clinical evaluations and 114 in preclinical development.60