Coronavirus Vaccine: China’s Kovid Front-Runner Uses Brute-Force Approach


Samples of inactivated Kovid-19 vaccine at the Synovac Biotech facility in Beijing on 16 March.

Photographer: Xinhua / Zhang Yuwei / Getty Images

many of More than 200 Kovid-19 vaccine projects worldwide focus on new technologies – based on messenger RNA, for example, or genetically modified cold viruses. In contrast, the company, which is developing one of China’s leading vaccine candidates, is betting that humanity’s best chance may lie with a shot that is no different than the one that has been in use for hundreds of years.

Beijing based Synovac Biotech Ltd, a company with a strong medical track record but a turbulent corporate history, began final phase trials on Coronavac in July. It relies on a passive version of the novel coronavirus to teach the human immune system to recognize and destroy the real thing. In terms of time, the company was ahead of most other potential vaccines, with new models to offer stronger protection and faster production facilities. Synovac candidate has a good chance of entering commercial production Modern Inc mRNA vaccine, or Is being developed by genetically modified shot Oxford University and AstraZeneca plc.

Synovac’s method is relatively crude, relying on the same principle as one Edward Jenner, an 18th-century British scientist sometimes called the father of immunology, when he first used vaccines against smallpox to treat mild Gomox virus. Was used. But it can just work — and it can be easier to use than other companies have never done before.

Vaccine expert Michael Kinch of Washington University in St. Louis says, “We should not forget to learn about history and the work that has been done in the past.” “Don’t imagine it until it becomes easy for you too.”
It is the case that conventional vaccines may be most effective in preventing Kovid-19, which is Around 800,000 people died worldwide. Many approaches to new vaccines focus on specific replication The “spike” protein on the surface of the coronavirus, which helps invade human cells. The data suggest that if the immune system could block that protein, the virus attack would explode significantly, if not stopped. But while it may be better to expose most or all of the body’s viruses, it gives a wider choice of potential targets and lets the immune system decide which ones are most vulnerable.

The advantage of a whole-virus approach is that “you’re ingesting a variety of proteins”, says William Hisaltine, a leading AIDS researcher who now chairs Access Health International Inc., a New York-based think tank. “Many of those proteins can induce cell-mediated immunity” – for example by so-called T cells, rather than just antibodies. He says, “This is clearly a possibility.”

Other benefits may emerge when the time comes to manufacture and distribute the shot. While no mRNA vaccine, for example, has never been licensed for human use, manufacturers have decades of experience with passive-virus inoculation, which is unlikely to cause production problems. And those vaccines usually do not need to be frozen, are an important boon in developing countries and rural areas where refrigeration capacity may be limited. (Coronavac, for example, can be stored between 36F and 46F.)

Inactive vaccines, on the other hand, may require multiple booster shots to achieve strong immunity, and production means handling large amounts of dangerous viruses. In theory, mRNA vaccines should also be very fast to manufacture, as they require only small amounts of raw materials to produce millions of doses.

Winning approval for Coronavac would be a huge coup for Synovac – and an attempt to keep the country at the forefront of vaccinating for Chinese President Xi Jinping. The company is led by Yin Weidong, who began his career in a public-health unit in the northeast city of Tangshan in the early 1980s. On the first day of his work he was assigned to a group investigating hepatitis outbreaks in the surrounding countryside. He went on to focus most of his career on preventing and controlling debilitating liver disease in rural China. He founded Synovac in 2001, not long before the earlier coronaviruses — which were the cause of severe acute respiratory syndrome, or SARS — to redeem the country. Synovac developed a potential SARS vaccine, but could be used before the disease could be cured. The company later gained approval for a shot targeting H1N1, or swine flu.

While Yin says that coronovirus infection had increased in China earlier this year, Synovac began evaluating its options to develop new vaccines. Everything was on the table, including a high-tech, genetically engineered approach. Company officials decided that a tried-and-true approach is the best chance of success in a fast-paced epidemic. “We had the technology ready,” Yin says. “Back in 2003, when we were developing vaccines for SARS, we learned a lot about the biology of coronoviruses, how to inactivate and grow it in batches.”

To produce its dormant virus, Synovac obtained samples of Kovid-19 pathogens from patients around the world and multiplied them into action cells, which are derived from the kidneys of monkeys. Then it inactivated the virus using beta-propylactone, a chemical derived from formaldehyde often employed in vaccine research, before purifying it into a product suitable for injection – in mice, rats, and primates, And then in preliminary studies in humans.

The company is awaiting data from its final phase of trials, including one A study of about 9,000 people in Brazil, which will determine if the vaccine is safe and can prevent the disease on a large scale. If the tests are successful, Synovac plans to produce at least 300 million doses in its own factories, while other manufacturers have to tap for further production.

However, investors wanting to get a piece of Synovac’s potential success will be disappointed. Its shares, which are listed on the Nasdaq, have been suspended from trading for more than a year, the result of a complex and unresolved dispute with some of its own investors. The play began in 2016, when two groups of shareholders — one led by Yin and the other by Pan Aihua, former patron of Yin and chairman of one of Synovac’s largest shareholders — offered to take the company private.

The board eventually approved Yin’s offer, bidding higher than Paan. Two years later, in 2018, a group of investors demanded the removal of Yin and several other executives from the board. In response, Synovac shifted its shares extensively to reduce the power of Yin’s critics, triggering a trading halt.

Stakeholders’ disputes remain before the courts, and in June Synovac said it could not anticipate that it would be able to resume business. This means that it has not recorded anything like Morden’s growing gains, with shares having tripled in value since the beginning of the year amid optimism about their Kovid-19 vaccine. Modernism now stands at about $ 27 billion – 60 times Synovac’s valuation at about $ 460 million, frozen since last year’s February.

All this is hardly a concern for the Chinese government, as its rapid vaccine development is identified as an important pane in its epidemiological geopolitical strategy – and an opportunity to show that its biotech companies Can compete best. Beijing regulators are fast-tracking approvals and allowing experimental vaccination to enter human trials at an unprecedented pace – for example, by collecting data to developers as it collects at the end of a research phase Allows Without those measures, Yin says, Synovac could not have entered the final phase of testing so quickly. Xi also promised Share any successful vaccine globally, which can build goodwill with poor countries, such as fear of closure by projects Operation Tana Pace, Trump Administration’s Commentary Program.

Many other Chinese companies are well involved in human trials, including Tianjin-based CanSino Biologics Inc., which has developed a vaccine that uses a harmless adenovirus to mimic the coronovirus spike protein — is a similar approach to the Oxford group. A medical research institute, affiliated with the Chinese military, meanwhile, is running a test for an mRNA vaccine, manufactured by Modern. Another front-runner, the state-controlled China National Biotech Group, is using a passive-virus approach that is similar to Synovac.

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