SAO PAULO (Reuters): A coronavirus vaccine developed by Sinovac Biotech in China was 78% effective at a late stage in Brazil without serious COVID-19 cases, researchers said on Thursday.
The trial results, which are being closely monitored by developing countries counting on the vaccine to launch mass vaccinations to end a raging pandemic, were among the preliminary findings of Turkish researchers and did not have detailed information on US and European vaccines. .
The director of the Brazilian biomedical center Butantan, Sinovac’s research and production partner, said detailed results were being submitted to health regulator Anvisa as part of a request for an emergency vaccination.
‘One thing is a presentation at a news conference. It’s something else to get and analyze the data, which Anvisa is going to do, ”said Cristina Bonorino, who sits on the scientific committee of the Brazilian Immunology Society. “If that’s what they say, it’s an excellent result,” she added.
Brazil and Indonesia, which have the most COVID-19 cases in Latin America and Southeast Asia respectively, are preparing this month to launch the vaccine, CoronaVac. Turkey, Chile, Singapore, Ukraine and Thailand also entered into offer deals with Sinovac.
Although the effectiveness of CoronaVac is less than the 95% success rate of vaccines from Moderna Inc or Pfizer Inc with BioNTech SE, it is easier to transport and can be stored at normal refrigerator temperatures.
The 78% efficacy rate is also well above the 50% to 60% benchmark set by global health authorities for vaccines developed early in the pandemic, given the urgent need.
Moderna and Pfizer / BioNTech announced detailed results of late-stage trials last year before receiving permits for emergency use in the United States and elsewhere.
Butantan director Dimas Covas told a news conference that full CoronaVac data would be released in an unspecified scientific publication, but that it did not provide a timeline.
Under pressure from journalists, Covas said there were 218 cases of COVID-19 in the trial of 13,000 volunteers. Just over 160 of the cases occurred among participants who received a placebo, and the remainder were in vaccinated volunteers.
Unlike other vaccine studies, the CoronaVac trial in Brazil included older volunteers, a particularly vulnerable population.
Covas said CoronaVac completely prevented serious COVID-19 cases among the vaccinated group, including the elderly. None of those who received the vaccine became ill enough to need hospitalization, he added.
MY DETAILS
Partial disclosure of the results of global CoronaVac studies has raised concerns about the transparency of the trials, which were not helped by Butantan’s news conference.
“It was not clear or transparent,” said Denise Garrett, an epidemiologist who worked for the United States Centers for Disease Control and Prevention (CDC) for 23 years. “They offered secondary outcomes on the prevention of mild cases, severe cases and hospitalizations, but not the effectiveness of preventing diseases.”
The partial disclosure by Butantan, which delayed the announcement three times, citing commitments to Sinovac, has led to skepticism about the Chinese vaccine in Brazil. Nearly half of Brazilians said in a December poll that they would not take a COVID-19 vaccine developed by China.
Brazilian President Jair Bolsonaro has expressed contempt for the Sinovac vaccine and doubts about its origin. He traded barbs with political rival João Doria, the governor of Sao Paulo, who is funding trials and production of the shot.
Still, Health Minister Eduardo Pazuello said Thursday that the federal government will buy Butantan’s full production of CoronaVac this year, and approach an agreement to buy 100 million doses for a national vaccination program.
Brazil has the world’s second deadliest outbreak to the United States, with a death toll exceeding 200,000 on Thursday, and aims to vaccinate 51 million people, or about a quarter of its population, in the first half of 2021 . [nL1N2JI32B]
Immunization has not yet begun. Doria reiterated that Sao Paulo, the country’s most prosperous and populous state, was expected to start vaccinating on January 25.
Based on the traditional vaccine technology that uses inactivated coronavirus to elicit an immune response, CoronaVac can be stored at 2-8 degrees Celsius (36 ° -46 ° F) and can remain stable for up to three years.
Vaccinations offered by Pfizer / BioNTech and Moderna use a new synthetic messenger RNA (mRNA) technology, which requires much colder temperatures for shipping and storage. The Pfizer / BioNTech vaccine must be kept at a sub-Arctic temperature, making it an inefficient option for poor countries and areas without the necessary refrigeration equipment.
Reporting by Eduardo Simões Additional reporting by Julie Steenhuysen, Ana Mano, Anthony Boadle and Beijing Newsroom Editing by Brad Haynes, Miyoung Kim and Bill Berkrot