Brazil Halts Trials of Chinese Coronavirus Vaccine Candidate After ‘Serious Adverse Events’

LAKEWOOD, CALIFORNIA - OCTOBER 14: A flu vaccine syringe rests on a table at a free flu vaccination clinic held at a local library on October 14, 2020 in Lakewood, California. Medical experts are hoping the flu shot this year will help prevent a ‘twindemic’- an epidemic of influenza paired …
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Brazil announced on Monday that it had halted final-stage trials for CoronaVac, a vaccine candidate for the Wuhan coronavirus developed by a Chinese company called Sinovac Biotech Ltd, due to “serious adverse events.”

According to the Brazilian institute that partnered with Sinovac for the trial, one of the volunteers died, although the death was reportedly not related to the vaccine.

The Brazilian Health Agency said on Tuesday that the adverse event occurred on October 29. It provided no further details, but the agency said its regulations called for the suspension of the vaccine candidate trial until review and analysis could be completed.

Director Dimas Covas of Instituto Butantan in Sao Paulo, Sinovac’s partner for local production of the vaccine candidate, said during a television interview that one of the volunteers died for reasons not directly related to the vaccine candidate. 

Sinovac issued a statement that said it was assured by Instituto Butantan that the fatality that caused the trial’s suspension was unrelated to the vaccine candidate. The Chinese Science Ministry claimed no “serious adverse events” have been reported among the 60,000 volunteers for its final-stage vaccine trials.

Brazilian President Jair Bolsonaro, who has been critical of the CoronaVac trials, hailed the suspension as a “victory” on his Facebook page.

“This is the vaccine Doria wanted to force everyone in São Paulo to take. Another victory for Jair Bolsonaro,” the president wrote.

“Doria” is Joao Doria, the governor of Sao Paulo, where Instituto Butantan is located. Doria is a fierce rival of Bolsonaro, seen as a likely challenger during the next presidential election in 2022. Doria has expressed a desire to make vaccination compulsory in his state if the trials are successful.

Another opposition governor, Flavio Dino of Maranhao, excoriated Bolsonaro, denouncing his remarks as “bizarre, irresponsible, and ridiculous.”

“Once more Bolsonaro has shown that he’s not worried about the lives and wellbeing of the population but simply his own ideological interests … Bolsonaro treats everything as an ideological war,” Dino said.

Protesters gathered in Sao Paulo and Rio de Janeiro on November 1 to demonstrate against coronavirus vaccine mandates and call for Doria’s removal from office. The demonstrators were angry with Doria for ordering shipments of the Chinese vaccine, insisting they would not be used as “guinea pigs” in a “socialist experiment.” Other Brazilians criticized Bolsonaro for stubbornly refusing to consider using the Sinovac vaccine, accusing him of being motivated by antipathy for Doria and China.

The Chinese pharmaceutical industry was rocked by major vaccination scandals before the advent of the Wuhan coronavirus, including large batches of defective vaccines administered to children. Angry Chinese parents accused their government of covering up serious problems at biotech companies favored by the Communist Party elite and downplaying health-threatening issues to avoid embarrassment. On one notable occasion in early 2019, a crowd of protesters in China’s Jiangsu province surrounded a health official and showered him with punches.

The CoronaVac trials cover seven states in Brazil, plus the federal district that contains the capital city of Brasilia. Sinovac has been authorized by Brazil’s health regulatory agency Anvisa to import six million doses, with the first shipment of 120,000 due to arrive in Sao Paulo on November 20.

“We will keep following health protocols to give the shots. They will only be taken to the public after a final authorization from Brazil’s health regulator,” Sao Paulo Health Secretary Jean Gorinchteyn promised on Monday.

The Chinese Foreign Ministry on Tuesday that the pause in CoronaVac trials was not due to health concerns about the vaccine. Chinese state media quoted Sinovac restating its confidence in the safety of the vaccine.


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