Coronavirus: Chinese vaccine starts final tests in Brazil
About 9,000 health workers across six Brazilian states will receive the vaccine, known as CoronaVac
A Chinese-made vaccine against the coronavirus entered the final stage of human testing in Brazil on Tuesday, where volunteers received the first doses of what officials hope will be a game-changer in the global pandemic.
The vaccine, developed by private Chinese pharmaceutical company Sinovac Biotech, became the third in the world to enter Phase 3 clinical trials, or large-scale testing on humans.
Phase 3 is the last step before regulatory approval. Phase 1 is about safety testing on a small number of people to check a dose and make sure it does not have severe side effects. Phase 2 is checking it has the right immune response.
"We're living in unique and historic times and that's why I wanted to be part of this trial," said a doctor, 27, who received the first dose at the Clinical Hospital of Sao Paulo.
About 9,000 health workers across six Brazilian states will receive the vaccine, known as CoronaVac, in two doses over the next three months under the study.
The initial results were expected within 90 days, Sao Paulo Governor Joao Doria said on Monday.
Sinovac is partnering with a Brazilian public health research centre, the Butantan Institute, on the trials.
If the vaccine proves safe and effective, the institute will have the right to produce 120 million doses under the deal, officials said.
Brazil is the second-hardest-hit country in the coronavirus pandemic, after the US.
Its death toll passed 80,000 on Monday, and it has registered more than 2.1 million infections.
Because the virus is still spreading quickly in the South American country, it is considered to be an ideal testing ground for vaccines.
Brazil is also helping to carry out Phase 3 testing of another experimental vaccine, developed by the University of Oxford and pharmaceutical company AstraZeneca.
It has a similar deal to produce that vaccine domestically if it is successful in tests, which are also being carried out in Britain and South Africa.
Brazilian health regulators announced on Monday that they had authorised Phase 1, 2 and 3 trials of two more vaccines, developed by US company Pfizer and Germany's BioNTech.
Researchers worldwide are racing to develop and test a vaccine for the virus. There are more than 150 projects so far.
Studies published on Monday in British medical journal The Lancet found two vaccines were safe and produced an immune response in Phase 2 trials.
They were the Oxford vaccine and another Chinese-made vaccine, developed by pharmaceutical firm CanSino Biologics and the Beijing Institute of Biotechnology.
Prof Sarah Gilbert, who is heading the Oxford University vaccine programme, said she was optimistic about the results.
“There is still much work to be done before we can confirm if our vaccine will help manage the Covid-19 pandemic but these early results hold promise," Prof Gilbert said.
The UK government has already signed a deal with the university and pharmaceutical company AstraZeneca to produce 100 million doses for the UK.
Shares in the company were up 0.4 per cent on the day after the positive findings were flagged last week.
Updated: July 22, 2020 02:28 AM