Clinical trials in Brazil of a Chinese-made vaccine against Covid-19 have shown “extremely positive” results, and a widespread vaccination campaign could begin as early as December, the governor of São Paulo state said.
“The results have been extremely positive,” Governor Joao Doria told a news conference, quoted by AFP. “We will soon be able to immunise Brazilians in São Paulo and across the country with the CoronaVac vaccine … The projected delivery date is in December this year.”
São Paulo, the epicentre of the coronavirus pandemic in Brazil, is one of six states helping to test the CoronaVac vaccine developed by Sinovac Biotech.
The vaccine produced an immune response in 98 per cent of recipients over 60 years old, with no adverse side-effects reported so far, Governor Joao Doria said Wednesday.
Sinovac has partnered with a Brazilian public health research centre, the Butantan Institute, to conduct Phase 3 clinical trials of the vaccine – the last step before regulatory approval.
The deal gives the institute the right to produce 120 million doses of the vaccine, according to officials.
CoronaVac has become caught up in a political battle in Brazil, however.
Brazilian President Jair Bolsonaro has criticised the vaccine, and lashed out at Doria, a leading opponent, for supposedly backing it.
Bolsonaro instead allocated 1.9 billion reals (US$360 million) to purchase another vaccine candidate, developed by Oxford University and pharmaceutical firm AstraZeneca.
Trials of that vaccine, which is also being tested partly in Brazil, were suspended on Tuesday after a volunteer recipient developed an unexplained illness – a move the company described as “routine”.
Brazil has the second-highest death toll in the pandemic after the United States, with more than 127,000 people killed and 4.1 million infections.