Chinese phase 2 trial finds COVID-19 vaccine is safe and induces an immune response

A phase 2 randomized controlled trial of a recombinant adenovirus type-5-vectored COVID-19 vaccine (Ad5-vectored COVID-19 vaccine) was conducted in China in April 2020 and involved more than 500 people. The primary objective of the study was to evaluate the immune response and safety of the vaccine, and to determine the most suitable dose for a phase 3 trial. Phase 3 trials are needed to confirm whether the vaccine candidate effectively protects against SARS-CoV-2 infection.