Covid-19 vaccine Photograph:( Reuters )
On Monday, the regulator, Anvisa, said in a statement that it had "ruled to interrupt the clinical trial of the CoronaVac vaccine after a serious adverse incident" on October 29.
Brazil's health regulator has suspended clinical trials of a Chinese-developed Covid-19 vaccine after an "adverse incident" involving a volunteer recipient.
On Monday, the regulator, Anvisa, said in a statement that it had "ruled to interrupt the clinical trial of the CoronaVac vaccine after a serious adverse incident" on October 29.
It said -- without giving details on what happened -- such incidents included death, potentially fatal side effects, serious disability, hospitalisation, birth defects and other "clinically significant events."
The setback for CoronaVac, developed by Chinese pharmaceutical firm Sinovac Biotech, came on the same day US pharmaceutical giant Pfizer said its own vaccine candidate had shown 90 per cent effectiveness.
Both the Pfizer and Sinovac vaccines are in Phase III trials, the final stage of testing before regulatory approval. And both are being tested in Brazil.
CoronaVac has been caught up in a messy political battle in Brazil, where its most visible backer has been Sao Paulo Governor Joao Doria, a top opponent of far-right President Jair Bolsonaro.
President Jair Bolsonaro has meanwhile labeled it the vaccine from "that other country," and pushed instead for a rival vaccine developed by Oxford University and pharmaceutical firm AstraZeneca.
Earlier on November 2, more than 300 Brazilians gathered on São Paulo's main commercial thoroughfare to protest state Governor João Doria's support for mandatory COVID-19 immunisation and testing the potential vaccine.
In São Paulo, the Sinovac vaccine was being tested as part of phase III clinical trials with support from the Doria government.
Brazil’s federal health ministry announced last month it would buy 46 million doses of the vaccine, contingent on regulatory approval, in a deal supported by state governors. But a day later, Bolsonaro said that Brazil would not buy the vaccine.
Bolsonaro has bashed China intermittently since the campaign trail in 2018, over the Asian countries growing investments and influence in Brazil.
The protestors in São Paulo rallied in support of Bolsonaro. Many of the tightly packed protestors did not wear masks.
Brazil has the third-worst outbreak of coronavirus globally, with over 5.5 million cases, after the United States and India