Coronavirus: Brazil suspends trial of Chinese vaccine due to serious adverse incident

Brazilian President Jair Bolsonaro has been vocal against CoronaVac and had said Brazilians 'will not be anyone's guinea pig’

A nurse shows a COVID-19 coronavirus vaccine produced by Chinese company Sinovac Biotech at Sao Lucas Hospital in Porto Alegre, southern Brazil. (Photo by SILVIO AVILA/AFP via Getty Images) (AFP via Getty Images)

The top health regulator of Brazil has suspended clinical trials of CoronaVac, a Covid-19 vaccine being developed by China, after an “adverse" incident.

“After the occurrence of a serious adverse event,” Anvisa, the Brazilian health regulator said it had “determined" the clinical study would be halted.  

In a statement, the regulator revealed that the event took place on 29 October. Following this, the trials were halted to “evaluate the data observed so far and judge the risk/benefit of continuing the study".

It added that in line with “national and international regulations” and in accordance with the “principles of confidentiality, human dignity and protection of participants”, the data on clinical research volunteers “must be kept confidential".

The health regulator said the interruption was part of the “good clinical practice procedures expected for clinical studies conducted in Brazil". 

Now with this decision, “no new volunteers can be vaccinated”, said Anvisa while reiterating its commitment to public health.  

In October, another volunteer involved in the clinical trial of the Covid-19 vaccine being developed by AstraZeneca and Oxford University died in Brazil but that trial was not suspended.

According to Anvisa, “adverse events” can include the death of a participant, persistent or significant disability, congenital anomaly or a birth defect.

CoronaVac vaccine is being developed by China’s Sinovac Biotech and tested by Sao Paulo state’s research centre.

Last month, Brazil announced a deal for acquiring and producing 46 million doses of the CoronaVac vaccine but the Brazilian President Jair Bolsonaro had said that his country won’t acquire it as there is lack of sufficient testing. “The Brazilian people will not be anyone's guinea pig,” he had said.

Across the world, there are nearly a dozen coronavirus vaccines that are under different stages of development including large scale trials in countries such as the United States, China, Russia and India.