Brazil’s health regulator suspended trials of China’s Sinovac coronavirus vaccine, prompting a potential setback for China as the United States begins embarking on new and effective developments to be ready by early 2021.
The suspension comes after a volunteer recipient suffered a “serious adverse event,” according to CNN. Chinese drugmaker Sinovac Biotech started Phase 3 trials of CoronaVac with Sao Paulo-based Brazilian Butantan Institute in July, finalizing the last step in vaccine testing before regulatory approval is sought.
Brazil’s National Health Surveillance Agency did not go into specifics about the incident over privacy concerns, but it said no new volunteers will be vaccinated as the study remains on pause.
Sinovac, which is also conducting trials in Indonesia and Turkey, expressed confidence in its vaccine in a statement put out on Tuesday, saying communications with the Butantan Institute allege the incident that occurred doesn’t have anything to do with the vaccine.
“Sinovac will continue to communicate with the Brazilian side on this matter,” the statement read. “Work related to our clinical research in Brazil will continue to be carried out in strict accordance with GCP (Good Clinical Practice) requirements.”
China and the U.S. have been locked in a race to develop a vaccine since the virus spread to the U.S. and other countries early this year, eventually leading to a global pandemic. China has followed the lead of the U.S. in conducting clinical trials for experimental vaccines and militarized its development back in the spring.
“We will not be slower than other countries,” said Wang Junzhi, a biological products engineer with the Chinese Academy of Sciences, in April.
Chinese leader Xi Jinping demanded quicker progress for a vaccine in March, and by April, China started enrolling volunteers for Phase 2 trials.
On Monday, Pfizer and BioNTech said one of its vaccine candidates had been found 90% effective in preventing COVID-19, sending stocks soaring. Health and Human Services Secretary Alex Azar said that he expects a coronavirus vaccine to be available to the general public by next spring.
The U.S. has surpassed over 10 million cases of the coronavirus and has had over 237,000 deaths. Globally, the virus has infected more than 50 million individuals.
