São Paulo (Reuters)-Researchers said on Thursday that a coronavirus vaccine developed by China Xinhua Biotechnology Co., Ltd. had an effective rate of 78% in a late trial in Brazil, with no serious COVID-19 cases, despite the lack The details of the data prompted calls for greater transparency.
Developing countries are paying close attention to the results of the trial and expect the vaccine to begin mass vaccination to help end the pandemic. This result is lower than the preliminary findings of Turkish researchers and lacks detailed data on vaccines in the United States and Europe.
The head of Sinovac’s research and production partner Brazilian Biomedical Center Butantan said that detailed results are being submitted to health regulator Anvisa as part of the emergency use of the vaccine.
“One thing is to give a speech at a press conference. Cristina Bonorino, a member of the Scientific Committee of the Brazilian Society of Immunology, said that this is another way to obtain data and analyze it. This is Anvisa (Anvisa) to do. She added: “If they said that, it would be a good result. “
Brazil and Indonesia, which have the most COVID-19 cases in Latin America and Southeast Asia respectively, are preparing to launch a vaccine called CoronaVac this month. Turkey, Chile, Singapore, Ukraine and Thailand have also reached supply agreements with Sinovac.
Although CoronaVac’s efficacy is much lower than the 95% success rate of Moderna Inc or Pfizer Inc and its partner BioNTech SE, it is easier to transport and can be stored at normal refrigerator temperatures.
In view of the urgent need, this 78% efficiency is much higher than the 50% to 60% benchmark set by global health authorities for vaccines developed at the beginning of the pandemic.
Moderna and Pfizer/BioNTech released detailed results of later trials last year, and subsequently obtained emergency use authorizations in the United States and elsewhere.
Butantan director Dimas Covas said at a press conference that all CoronaVac data will be published in unspecified scientific publications, but no timetable was provided.
Driven by reporters, Kovas said that there were 218 COVID-19 cases in the trial of 13,000 volunteers. He said that only more than 160 cases occurred among participants who received placebo, and the rest were vaccinated volunteers.
Unlike other vaccine studies, Brazil’s CoronaVac trial included elderly volunteers, a particularly vulnerable population.
Covas said CoronaVac has completely prevented severe COVID-19 cases among vaccinated people, including the elderly. He added that none of the vaccinated people was sick enough to be hospitalized.
The fragmentary disclosure of CoronaVac research around the world has caused people to worry about the transparency of the trial, but Butantan’s press conference did not help.
Denise Garrett, an epidemiologist who has worked for the Centers for Disease Control and Prevention (CDC) for 23 years, said: “It’s not clear or transparent.” “They proposed the prevention of mild cases and severe cases. The secondary result of hospitalization and hospitalization, but no disease prevention effect.”
Part of Butantan’s disclosures postponed the announcement three times on the grounds of its obligations to Sinovac, which increased people’s suspicions about the Brazil-China vaccine. A poll in December showed that nearly half of Brazilians said they would not take the COVID-19 vaccine developed in China.
Brazilian President Jair Bolsonaro dismissed the Sinovac vaccine on the grounds that he doubted its “origin.” He entered into a barbed deal with João Doria, the political opponent of the governor of Sao Paulo, who is funding test shots and lens production.
Despite this, Health Minister Eduardo Pazuello said on Thursday that the federal government will buy all Butantan’s CoronaVac products this year, close to an agreement to purchase 100 million doses of vaccine for the national immunization program.
Brazil is the second largest epidemic in the world after the United States, with more than 200,000 deaths on Thursday, and plans to vaccinate 51 million people or 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 richest and most populous state, is expected to start vaccination on January 25.
Based on traditional vaccine technology that uses inactivated coronavirus to trigger an immune response, CoronaVac can store temperatures of 2-8 degrees Celsius (36°-46°F) and can maintain stability for up to three years.
The vaccines provided by Pfizer/BioNTech and Moderna use a new type of synthetic messenger RNA (mRNA) technology, so the temperature required for transportation and storage is much lower. The Pfizer/BioNTech vaccine must be kept below the Arctic temperature, which is an ineffective option for poor countries and regions without the necessary cold storage equipment.
Reporting by Eduardo Simões by Julie Steenhuysen, Ana Mano, Anthony Boadle and other reports by Beijing Newsroom Brad Haynes, editors by Miyoung Kim and Bill Berkrot