Instituto Butantan conducts pioneering study to assess the effectiveness of CoronaVac/Sinovac vaccine
Projeto S: Assessing the effectiveness of the CoronaVac/Sinovac vaccine during the pandemic
The Instituto Butantan in São Paulo, Brazil has funded a study to assess the impact of the CoronaVac/Sinovac vaccine on the incidence of cases among immunized individuals as well as COVID-19-related hospitalizations and deaths, and the indirect effects of the vaccine among unvaccinated individuals.
For this stepped-wedge, randomized clinical trial conducted over an eight-week period (during epidemiological weeks 6 to 19 in 2021), the vaccine was administered in two doses to 27,000 people in the town of Serrana, Brazil, representing 81.3% of the adult population (Serrana has a total population of 45,000 inhabitants). No placebo was used. The primary endpoint was the incidence of symptomatic cases in fully immunized individuals. The secondary endpoints were COVID-19-related hospitalizations and deaths and incidence according to immunization coverage. The study was funded by GloPID-R members Fundação Butantan and São Paulo Research Foundation (FAPESP). The CoronaVac/Sinovac vaccine was developed by Butantan and Sinovac Biotech. The project has been published on the SSRN platform.