Chinese company Sinovac Biotech’s Covid-19 vaccine, CoronaVac, has reportedly passed the 50% threshold for efficacy and demonstrated its effectiveness in late-stage trials carried out in Brazil.

Brazil has already concluded the Phase III trials of the vaccine. Indonesia and Turkey are also testing the vaccine.

The Wall Street Journal quoted the people involved in the Brazilian trials as saying that the results demonstrated CoronaVac to be effective with a rate above 50%.

Scientists tracking the development of the vaccine expect it to have efficacy that is similar to other vaccines for Covid-19 that demonstrated an efficacy of 95% in trials.

The newspaper quoted Ribeirão Preto Medical School professor Domingos Alves as saying: “Everyone is hoping for an efficacy rate above 90%. The results from the first phases of the trials were very good.”

São Paulo government-supported Butantan Institute in Brazil had been testing CoronaVac and is set to announce the vaccine’s efficacy rate on 23 December.

Butantan said any reports on the efficacy of the shot before the date were ‘mere speculation’.

In November, Brazil National Health Surveillance Agency Anvisa suspended a clinical trial of Sinovac’s Covid-19 vaccine, CoronaVac, due to a severe adverse reaction.

Later, Anvisa authorised the resumption of the Phase III clinical trial of CoronaVac.
SinoVac noted that Anvisa failed to receive the data sent by the Butantan Institute on time and it urgently suspended the study.

A report from the Data and Safety Monitoring Board (DSMB) was submitted to Anvisa and after evaluating it, it gave permission to resume the clinical research.