By Samantha Pearson and Luciana Magalhaes
Brazil was expected to announce efficacy rate from Phase 3 trials on Wednesday
SÃO PAULO—Chinese firm Sinovac Biotech Ltd. has delayed the announcement of results from late-stage trials of its Covid-19 vaccine to January as it consolidates data from Brazil with test results from Indonesia and Turkey.
Brazil, which is the first country to complete Phase 3 trials of CoronaVac, had been expected to announce the vaccine’s efficacy rate on Wednesday. However, Brazil’s Butantan Institute, the research center backed by São Paulo’s state government that has been testing CoronaVac, said Sinovac asked for 15 more days to analyze the data together with results from other trials of the vaccine, which is also being tested in Indonesia and Turkey.
“There can’t be three efficacy results for the same vaccine,” said Butantan’s director, Dimas Covas. He said the delay had nothing to do with the efficacy of the vaccine, which is expected to be one of the first approved for use in Brazil.
Scientists tracking the vaccine had hoped CoronaVac would be comparable to other Covid-19 vaccines that have shown to be as much as 95% effective.
“It was very frustrating…this is the only vaccine we have at the moment on Brazilian soil,” said Luiz Carlos Dias, part of a Covid-19 task force of researchers at the University of Campinas in São Paulo state. “I’m worried that perhaps the efficacy rate is not so high after all.”