Test-tuned COVID vaccine aims to dodge variants | News

Dozens of Americans are rolling up their sleeves for a third dose of the COVID-19 vaccine-this time we’ve tweaked the shots to prevent the mutant version of the virus of interest.

There is no mistake. Vaccines currently deployed nationwide provide strong protection. However, new research on updates of the Moderna and Pfizer vaccines shows an important first step towards alternatives if the virus eventually surpasses today’s shots.

“We need to be ahead of the virus,” said Dr. Nadine Rufael of Emory University, who is helping to lead the study of Modana’s fine-tuned candidates. “I know what it’s like when I’m late.”

It’s not clear if protection will be weakened and will need to be updated, but “in reality, we want to turn COVID into a sniffle,” she added.

The virus is constantly evolving and the world is competing to vaccinate millions of vaccines and get rid of the coronavirus before more mutants emerge. According to the US Centers for Disease Control and Prevention, more than 119 million Americans have been vaccinated at least once, and 22% of the population is fully vaccinated. Many other parts of the world are far behind that pace.

The already popular version, found in the United Kingdom just a few months ago, has become the most common variant currently in circulation in the United States. Fortunately, vaccines can prevent it.

However, there are concerns worldwide that first-generation vaccines may have less protection against another variant that first appeared in South Africa. All major vaccine manufacturers are adjusting their recipes in case an update to the so-called B.1.351 virus is needed. Experimental doses from Moderna and Pfizer are currently being tested.

In the suburbs of Atlanta, Emory asked people who received Modana’s original vaccine a year ago to help test the updated shots in a first-stage study. Volunteer Cole Smith said returning home was not a difficult decision.

“The previous one was a huge success, and as you know, millions of people are now vaccinated,” Smith told The Associated Press. “If we are helping people with the old, why not volunteer and help people with the new?”

This study, funded by the National Institutes of Health, is not just testing Moderna’s mutant vaccine as a third-shot immune booster. Researchers at Emory University and three other medical centers have also registered volunteers who have not been vaccinated with COVID-19.

They want to know: Can people be vaccinated with just two doses of the variant vaccine instead of the original vaccine? Or one dose of each type? Or can the original and variant doses even be combined in the same injection?

Separately, the Food and Drug Administration has granted Pfizer and its German partner BioNTech permission to begin similar testing of its own fine-tuned vaccine. The two companies call it part of an aggressive strategy to enable the rapid deployment of the latest vaccines as needed.

The Moderna and Pfizer vaccines, like most of the COVID-19 vaccines used worldwide, train the body to recognize the peplomer, the outer skin of the coronavirus. These spikes are the way the virus latches into human cells.

Mutations occur every time the virus makes a copy of itself. Usually these mistakes make no difference. However, if there are many changes in the peplomer, or if those changes are in a particularly important location, the mutant can escape the immune system prepared to monitor intruders that look a little different. There is sex.

Good news: Updating the Moderna and Pfizer vaccines is pretty easy. They are made up of part of a genetic code called messenger RNA. Messenger RNA tells the body how to make harmless spike copies that train immune cells. The two companies simply exchanged the genetic code of the original vaccine for the mutated peplomer mRNA. This time it’s from South Africa.

The study going on this month involves hundreds of people, which is very different from the large-scale testing required to prove that the original shot works. Scientists need to make sure that mRNA substitution does not cause a variety of side effects.

On the protective side, we are closely measuring whether the renewed vaccine encourages the immune system to produce antibodies. Antibodies prevent infection as strongly as the original shot. Importantly, lab tests can show whether these antibodies recognize not only South African variants, but other more common viral versions.

Some good news: Antibodies are not the only defense. NIH researchers recently examined T cells that counterattack after the onset of infection, another arm of the immune system. Lab tests have shown that T cells in the blood of people who have recovered from COVID-19 long before the mutant of interest appears recognize the mutation from South Africa. Vaccines also cause T cell production and can be key to prevent the worst consequences.

Still, no vaccine is 100% effective. A fully vaccinated vaccine can become infected with COVID-19 even without the threat of mutation. So how do authorities know that an update is needed? The danger signal will be a surge in hospitalizations, as well as positive tests, among vaccinated people carrying the new mutants.

“That’s when you cross the line, when you’re talking about second-generation vaccines,” said Dr. Paul Offit of the Philadelphia Children’s Hospital, Vaccine Advisor at the Food and Drug Administration. “We haven’t crossed that border yet, but we may.”

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Atlanta Associated Press journalist Ron Harris contributed to this report.