RIO DE JANEIRO: Brazilian biomedical center Butantan will announce the average efficacy of the CoronaVac vaccine on Tuesday in a press conference, Sao Paulo state health secretary Jean Gorinchteyn said in an interview to GloboNews TV.

The vaccine, by China's Sinovac Biotech, was 78% effective in a late-stage Brazilian trial with no severe COVID-19 cases, researchers said on Jan. 7. But they did not disclose full trial details including the average efficacy.