As the global vaccination campaign scrambles to stay ahead of the new Covid-19 variants, pioneer scientists have set out to prevent past, present and future coronaviruses by developing a vaccine to alleviate concerns about another pandemic.
Melanie Saville, Head of Vaccine Research and Development of the Alliance for Epidemic Prevention Innovation, was one of the people leading the accusation. She called for the development of a vaccine that would broadly prevent all beta coronaviruses and any “possibility.” Of the new strain. In the future, we will jump from animals to humans.”
“[The] The strategy to move forward revolves around two key issues,” she told the Financial Times. “What do we need to do to end this pandemic, and then what do we need to do to prevent the next pandemic? “
In the past 18 months, Sars-Cov-2 has caused nearly 4 million deaths, and it is at least the third so-called beta coronavirus that has spread among humans in the past 20 years. Common virus families in bats and rodents also include SARS-Cov-1, which killed more than 700 people in 2003, mainly in China and Hong Kong, and Mers-Cov, which was first discovered in Saudi Arabia and caused Since 2012, more than 850 people have died.
Given that Covid-19 is unlikely to be the last coronavirus to infect humans, developing a vaccine that can prevent all such diseases has become a central focus of some scientists. As Covid-19 continues to mutate faster than originally expected—and recently with the rapid spread of the Delta variant first discovered in India—people’s interest in their work has increased.
England’s chief medical officer, Professor Chris Whitty, told British healthcare workers this month that within five years, “multivalent vaccines” against different coronaviruses “will largely resist and even new variants”.
But the road to so-called multivalent or multivalent vaccines is full of challenges. For decades, researchers have been unsuccessful in finding an HIV vaccine—a disease that often produces new strains—and the flu vaccine still needs to be updated annually.
The current Covid-19 vaccine has proven to be very effective against the original Sars-Cov-2 strain and its subsequent variants. They focus on producing antibodies to neutralize the spike protein used by the virus to enter human cells. Saville explained that the difficulty with this approach is that “the virus evolves to evade this immune response… you need to constantly update your vaccine.”
In contrast, multivalent vaccines usually target protein fragments in the virus that stimulate the immune system, called epitopes, and specifically attack epitopes that are not mutated in parts of the virus, even under “evolutionary pressure,” Saville said. Many of these injections also attempt to stimulate the production of T cells-in addition to antibodies-T cells have gradually emerged and are an important part of the immune response to Covid-19.
Paul Higham, CEO of Valo Therapeutics, said that by targeting epitopes with a “very, very low” mutation rate, its multivalent vaccine can generate a T cell response, which can be used for Covid-19, Sars, Mers and “Future Coronavirus” . Hiram hopes that the Helsinki and Oxford-based company will be able to prepare the vaccine for clinical trials by the end of the year, adding that it can be made available to the public “sometime in 2022.”
However, it is extremely difficult to develop vaccines against multiple pathogens. “The further the composition and sequence of the virus, the harder it is to find antibodies that can fight the virus. [them],” Dennis Burton of the Scripps Research Institute in California explained that he has been looking for an HIV vaccine for many years.
“For example, Sars-1 and Sars-2 are very similar, and we have found that many antibodies can fight against these two viruses.” But he said that the scope should be expanded to target Mers at the same time, not to mention the more diverse coronaviruses in the future. The difficulty is much greater.
CEPI’s Saville believes that finding epitopes that provide protection against multiple coronaviruses will require the use of artificial intelligence, which is increasingly being used in drug discovery to accelerate research and development.
John Lewis, CEO of Entos Pharmaceuticals, said his company has adopted a “machine learning approach” to its multivalent vaccines. It cooperates with a professional AI company, and its software enables it to recognize “34 different epitopes from different coronavirus proteins” to generate the most effective human T cell response.
“The protein fragments we used have more than 90% similarity between Sars-1 and Sars-2, and they have also been found in other types of coronaviruses, and they seem to confer broad immunity,” he said. “They may not provide complete protection, but they should provide partial protection for many different species.” Entos is headquartered in Edmonton, Canada, and hopes to start human trials within the next two months.
French biotech company OSE Immunotherapeutics uses an AI algorithm that has previously been used to develop cancer vaccines. This technology makes it possible to identify 12 epitopes for 11 proteins, most of which are located in the virus rather than on the surface of the virus. CEO Alexis Peyroles explained: “Because they are in the virus, they do not mutate or mutate very little”, adding that it is possible in both Sars-1 and Mers Find the same type of protein.
The first phase of the jab has already begun on human subjects, and the results are expected to be available in September. With the financial support of French innovation bank BPI France and the possible help of the third phase of the experiment in 2022, OSE is already “loosely planning” the second phase.
Peyroles said the vaccine may be particularly effective for people with suppressed immune systems who have not produced protective antibodies against currently available vaccines. But its broader use is as a pan-coronavirus booster for everyone, and it is easy to adapt to new forms of disease. He said: “You will have a base that you can keep, and then add or delete new epitopes based on the new coronavirus.”
VBI Vaccines, located in Cambridge, Massachusetts, took a different approach. Like the current Covid-19 vaccine, VBI’s JAB targets the spike protein, but it has been able to generate a broader immune response. “When we vaccinated animals, we made antibodies that can protect against Covid-19, Sars, and Mers-it’s like making antibodies that can see red, yellow, and blue,” Chief Science Officer David Anderson Say.
“But the immune system is very flexible. You can teach it to see something between red and yellow, or between yellow and blue,’spike protein’. So now they see orange or green shades, which shows You basically expanded the immune response,” he continued. “The idea is that these antibodies may now track variants that will continue to mutate and emerge over time.”
The company’s “broad-spectrum approach” has no precedent, but Anderson is optimistic. The vaccine has received financial support from CEPI and the Canadian government, and human trials are expected to begin in the second half of this year.
Jeff Baxter, VBI’s chief executive, said that it may be considered with regulators within 12 to 14 months. “Science is not always what you want, it will continue to evolve as we learn more,” he said. “But it’s really exciting to think that in two years, everyone can get a multivalent pan-coronavirus vaccine.”