As the world continues to battle Covid-19, a study on the efficacy of Chinese Sinovac Biotech’s vaccine, published in the British journal The Lancet, has found that it generated lower levels of protective antibodies than those present in recovered Covid-19 patients.
The study, based on initial clinical trials, shows the candidates from American companies Pfizer and Moderna were found to be more than 90% effective. Britain’s AstraZeneca had an overall efficacy rate of 70%.
NEW—Chinese #COVID19 vaccine candidate (CoronaVac) based on inactivated SARS-CoV-2 virus appears safe & induces an immune response in healthy volunteers: finding from a randomised, double-blind, placebo-controlled, phase 1/2 clinical trial @TheLancetInfDis https://t.co/0AC0fP53dI pic.twitter.com/W3gMdqLzTG
— The Lancet (@TheLancet) November 18, 2020
Beijing was leading the global race of developing a Covid-19 vaccine but the US and European pharmaceutical firms that started the development of vaccines much later than China are close to bringing their products to the market.
The Lancet study has confirmed the presence of antibodies and found no safety problems, sufficient evidence to continue with clinical trials. Sinovac senior director Meng Weining has said that phase 3 trials are running smoothly and the data will be available next month.
“Our findings show that CoronaVac is capable of inducing a quick antibody response within four weeks of immunization by giving two doses of the vaccine at a 14-day interval,” the researchers said in the study.
However, it doesn’t create “the same excitement as Moderna and Pfizer/BioNTech’s phase 3 top-line peek this month, which showed their vaccines could offer 90%-plus efficacy”, according to a report in Fierce Biotech. However, their data still need to be published in full and peer-reviewed because they were later-stage efforts with different endpoints than the early tests from Sinovac, the website has reported.
Eleven vaccine candidates worldwide are in final clinical trials, and four of them are Chinese-made. Sinovac is also undertaking phase 3 trials in Turkey, Indonesia, and Brazil.
Earlier this month, one phase 3 trial of Sinovac was stopped in Brazil after reports of a serious safety concern, with one report stating a death is involved but that it was not in the vaccine arm.
Trial organizers have said Brazil has gathered enough infection data from a late-stage trial of an experimental Covid-19 vaccine developed by China’s Sinovac Biotech and expects to have interim results on its efficiency in early December.
Meanwhile, a Reuters report said that Britain’s AstraZeneca Plc joined its US rivals Pfizer and Moderna, and Russia in announcing positive results in pivotal trials, raising hopes that the world would soon have successful vaccines to end the pandemic.
Another concern raised regarding the Chinese vaccine is the safety of its coronavirus inoculations while the country speeds a large-scale rollout despite the candidates remaining in the clinical trial phase.
Sinovac and state-owned giant Sinopharm Group have ramped up inoculations at home. Nikkei Asia has shared a picture of people lined-up to receive inoculations at a Sinopharm research lab in Beijing.
The company has claimed that nearly 1 million people have received inoculations. The media report underlines that inoculations of individuals such as employees of state-owned companies have nearly tripled over the past two months but Sinopharm has made no attempt to contact them post-inoculation.
The absence of such contact raises concerns about the effort being made to check on the health of people receiving a vaccine under development. “After close to 1 million inoculations, there has not been a single adverse reaction,” Sinopharm Chairman Liu Jingzhen has said in a statement.
Sinopharm could start moving from emergency administration of the drug to preparation to general sales as the company has applied to China’s national drug administration on Wednesday for permission to sell the vaccine candidate, state-owned Xinhua News Agency reported.
Current full dose AstraZeneca regimen resulted in 62% efficacy. If they go for a new clinical trial, we suggest trying a regimen of combining the AZ shot with the #SputnikV human adenoviral vector shot to boost efficacy. Combining vaccines may prove important for revaccinations.
— Sputnik V (@sputnikvaccine) November 26, 2020
Meanwhile, Russia’s vaccine Sputnik V has also shown 90% efficacy. The developers of the Sputnik V vaccine have suggested that AstraZeneca try an experimental regimen during a new round of its Covid-19 vaccine trials as both the vaccines are based on adenoviral vectors, which deliver parts of the virus genome to the cell.