Coronavirus Global situation
Brazil halts trial of China's Sinovac vaccine
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Health worker and volunteer Fabiana Souza receiving a Covid-19 vaccine produced by Chinese company Sinovac at the Sao Lucas Hospital in Porto Alegre, southern Brazil, on Aug 8.
PHOTO: AGENCE FRANCE-PRESSE
SAO PAULO/BEIJING • Brazil's health regulator has suspended a clinical trial for China's Sinovac Covid-19 vaccine, citing a severe adverse event, surprising the trial organisers who countered that there had been a death but it was unrelated to the vaccine.
The health regulator, Anvisa, on Monday said the event occurred on Oct 29 but did not specify if it was in Brazil or another country. It also did not say how long the suspension might last.
The trial is one of three large late-stage trials under way for the Sinovac vaccine. However, the vaccine has faced controversy in Brazil, with President Jair Bolsonaro dismissing it as lacking credibility. He also regularly expresses anti-Chinese sentiment.
The setback to Sinovac's efforts contrasts with good news from Pfizer, which said its experimental Covid-19 vaccine is more than 90 per cent effective based on initial trial results.
Mr Dimas Covas, the head of Sao Paulo's medical research institute Butantan which is conducting the Sinovac trial, said the regulator's decision was related to a death but added that he found it strange "because it's a death unrelated to the vaccine".
"As there are more than 10,000 volunteers at this moment, deaths can occur... It's a death that has no relation with the vaccine and, as such, it is not the moment to interrupt the trials," Mr Covas told local broadcaster TV Cultura.
Sinovac said in a statement on its website yesterday that it was confident of the safety of its vaccine and will continue to communicate with Brazil on the matter. It previously said it expected interim results of late-stage trials this year.
It is not uncommon for clinical trials to be suspended temporarily - sometimes for as short as a week - after a volunteer dies or takes ill, so that trial organisers can check whether the event is related to the drug being tested.
Sinovac's vaccine is among the three experimental Covid-19 vaccines that China has been using to inoculate hundreds of thousands of people under an emergency use programme.
A Chinese health official said on Oct 20 that serious side effects had not been seen in clinical trials.
Brazil has more than 160,000 dead and over 5.6 million confirmed cases of the coronavirus.
REUTERS
