China is getting closer to passing his first mRNA vaccine to protect people against COVID-19. In a small clinical trial, the Chinese vaccine candidate triggered a stronger antibody response in vaccinated adults when given as a booster injection than an injection containing inactivated SARS-CoV-2, the vaccine platform the country has mostly relied on until now.
The experimental puncture, called ArCoV, es a strong candidate to become the first approved mRNA vaccine in China. But what it would mean for the government’s handling of the pandemic is hard to know, researchers say.
A highly effective mRNA vaccine it would reduce the chances of widespread serious infections that could overwhelm hospitals. Nevertheless, unlikely to end the country’s strict “zero COVID” strategy, which uses mass testing and lockdowns to nullify all infections, according to a recent investigation published in the scientific journal Nature.
So far, the Chinese drug regulator has approved seven vaccines against COVID-19. Most Chinese residents are vaccinated with one of two inactivated virus vaccines, either CoronaVacmanufactured by the company Sinovac based in Beijingo BBIBP-CorVmanufactured by the state company Sinopharm in Beijing.
Las inactivated virus vaccines are effective in reducing the risk of hospitalization and death, but provide less protection that the two vaccines of mRNA developed by Pfizer-BioNTech and Moderna, which have been widely used outside of China. “From the data of all the COVID-19 vaccines available in the world, mRNA technology seems to be better compared to other technologies”, warns Feng Gao, virologist of the Jinan University in Guangzhou, China.
chinese companies they had planned to import the mRNA vaccine made by BioNTech and Pfizer. As early as March 2020, a pharmaceutical company based in Shanghai, Fosun Pharma, reached an agreement with BioNTech to sell your vaccine in China continental and in Hong Kong once regulators gave the product the green light.
But approval of the highly effective vaccine is still pending on the continent, despite data from a phase II trial in China showing that the vaccine triggers a robust immune response and is safe to use in adults.
The reasons for the delay are not clear, but it’s probably policyaccording to Yanzhong Huang, Chinese health policy specialist at the Council on Foreign Relations of New York City. The Chinese government has accepted foreign clinical trial data to speed up drug approval processes since 2017.
And the drugs that are urgently needed, like vaccines during a pandemic, they can receive expedited reviews. “There is no other reason to explain the delay except techno-nationalism”, dice Huang and ensures that the Chinese government would probably prefer its first mRNA vaccine to be a home injection like ARCoV.
At least six vaccines domestic of mRNA are in clinical trials. ARCoVmanufactured by the biotech start-up based in Suzhou, Abogen Biosciencesis the most advanced and is currently being evaluated in a multicenter phase III trial in Mexico e Indonesia.
The little essay ARCoVwhich was published as preprint on May 31 and has not been peer reviewed, involved 300 adults in China who had received 2 doses of an inactivated virus vaccine 6 months before receiving the booster. The researchers found that after an ARCoV injection, levels of neutralizing antibodies targeting the Omicron variant of the coronavirus were four times higher than after a booster con CoronaVac. Neutralizing antibodies can prevent the virus from infecting a cell, and are thought to its levels are correlated with the protective strength of the vaccines.
“The results demonstrate a superior antibody boost of the mRNA vaccine versus an inactivated vaccine for the third dose,” Explain Ben Cowling, epidemiologist of the University of Hong Kong. However, even though research previous have shown that mixing vaccine types can deliver a stronger immune response, “without comparing these different booster strategies side by side, it’s hard to say which vaccine is better,” he says Gao.
If there vaccine ARCoV “will receive official approval will depend on the outcome of its phase III trial. Not all mRNA vaccine candidates will be successful.” argues Gao. “If approved, ARCoV could be used both as part of the country’s standard COVID-19 vaccination program and as a booster.” add.
A pandemic dilemma
Los studies have shown that booster shots are vital to protect people, especially the elderly, from serious illness and death when infected with Omicron. But in China continental, only 60% of people age 60 and over have had a booster shot, which means that 100 million people in that age group have not received it. Booster coverage is much lower for people aged 80 and older: fewer than 20% of them had received a booster shot in March, when the Omicron wave began to rise.
Gao say what it’s hard to know whether unvaccinated people would accept an approved mRNA vaccine, since the technology is new. “But from a scientific perspective, they should, because mRNA vaccines tend to induce a stronger immune response, especially in the most vulnerable people.” Add.
For many countries, the widespread acceptance of COVID-19 vaccines has been a factor that has led governments to decide to open and reduce movement restrictions, reduce mass testing and relax isolation requirements. But the researchers say even with a highly effective mRNA vaccine, Chinese officials are unlikely to change its zero COVID approach, which has managed to contain outbreaks for much of the pandemic, but has been less successful against the highly transmissible Omicron variant.
Officials have said little about the opening. But in April Wannian Liang, head of the panel of experts National Health Commission, said chinese could “defeat the pandemic” when cities have adequate medical resources and high vaccination coverage, especially in the elderly and other vulnerable groups. He also said the government would consider whether future variants had a lower mortality rate than those currently circulating when deciding to open the country. But many virologists have questioned the idea that the variants will weaken over time.
Huang warns that The government’s unwillingness to tolerate even a low number of COVID-19 cases has created a dilemma: local officials have limited incentive to increase vaccination and booster rates, and, instead, they order their health workers to carry out tasks such as mass testing. “The situation won’t change unless officials change mentality to allow infection to a certain extent,” he says.
A more effective vaccine could ease governments’ fears of relaxing some restrictions. “With better vaccines and greater access to COVID-19 pills, China should worry less about COVID-19 overwhelming its health care system. Maybe the government will change its mind then.” Huang.