Phase 2 randomised 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
Promising early stage results from a phase 1/2 clinical trial of the UK's vaccine candidate against SARS-CoV-2 (the virus that causes COVID-19) are published today in The Lancet.
The early stage trial finds that the vaccine is safe, causes few side effects, and induces strong immune responses in both parts of the immune system - provoking a T cell response within 14 days of vaccination (ie, a cellular immune response, it could find and attack cells infected with the virus), and an antibody response with 28 days (ie, humoral immune response, it could find and attack the virus when it was circulating in the blood or lymphatic system).
