This is a phase III clinical trial to assess efficacy and safety of the Adsorbed COVID-19 (inactivated) vaccine manufactured by Sinovac in health care professionals.~The study will be double-blind placebo-controlled trial with participants randomly allocated 1:1 to placebo and vaccine arms.~The immunization schedule is two doses intramuscular injections (deltoid) with a 14-days interval.~For efficacy, the study aims to detect COVID-19 cases, defined as symptomatic SARS-CoV-2 infections, after the second week post-immunization schedule.~For safety and immunogenicity, participants are categorized in two age groups, Adults (18-59 years) and Elderly (60 years and above). Safety database aims to detect adverse reactions with frequency of 1:1000 or higher in adults and 1:500 in elderly.~All participants will be followed up to 12 months. Interim preliminary efficacy analysis can be triggered by reaching the target number of 61 cases. Primary efficacy analysis requires 151 cases.
This is a phase III clinical trial to assess efficacy and safety of the Adsorbed COVID-19 (inactivated) vaccine manufactured by Sinovac in health care professionals