Moderna Provisional results announced on Wednesday We call the latest coronavirus vaccine targeting Omicron variants “our key candidate” to act as a booster shot in the United States in the fall.
The company’s researchers tested booster doses that combined the original vaccine with a vaccine that specifically targeted the mutant Omicron, which prevailed last winter. They found that, in the absence of previous evidence of coronavirus infection, this combination produced 1.75-fold levels of neutralizing antibodies against Omicron compared to the existing Coronavirus vaccine alone.
While these results may seem promising, many experts say that the virus evolves rapidly and outperforms its ability to change vaccines, at least as long as the United States relies on human clinical trials for results. I am worried that I am.
Moderna’s new findings from a clinical trial of 814 volunteers show that one month after being given a booster shot, the updated vaccine has a significantly stronger immune response to Omicron than existing vaccines. It shows that it has been brought. Booster shots followed the previous three doses of Moderna’s vaccine.
However, Omicron has been producing subvariants for months, and some vaccine experts say how well the new booster formulation protects against the latest subvariants BA.4 and BA.5, not Omicron itself. Some say it’s important to be able to do it. These two submutants, first detected in South Africa earlier this year, now account for 13% of new cases in the United States and are expanding rapidly. According to some estimates, within a month it may surpass the other two currently dominant Omicron subvariants BA.2 and BA.2.12.1.
Moderna did not release data on how the updated vaccine worked against BA.4 or BA.5. In a presentation Wednesday morning, the company’s president, Dr. Stephen Hogue, said researchers are still collecting data on them and other subvariants.
However, he found that from very small samples and other isolated studies, the levels of neutralizing antibodies caused by the updated vaccine were BA.4 compared to those caused against Omicron. And said it suggested that it was 2-3 times lower than the BA.5 subvariant. However, he said these levels were “still a very comfortable place” and that at least one federal health authority who reviewed the data reflected this view.
Moderna officials said it was not yet known if the reconstituted vaccine would provide more lasting protection than existing vaccines, but it was reconstituted for another variant released in April. I was hoping based on previous findings from the vaccine research.
The latest subvariants appear to spread even faster than previous versions of Omicron and may be better at dodging immune system defenses. It is unclear if they cause more serious illness. In an interview on Tuesday, White House Chief Medical Advisor Dr. Anthony S. Forch said in South Africa, where BA.4 and BA.5 are widespread, “hospitalization has increased slightly, but ICU utilization has been modest. It has risen. ” And the dead remain really stable and low. “
In any case, given the speed of virus mutation, it makes sense for some vaccine experts to target the latest version rather than the form of the virus that has already been or will soon be overtaken. Some say they are.
The problem is that Moderna and Pfizer, other major coronavirus vaccine makers in the United States, have conducted more human clinical trials and still make shots by the fall, hoping that the Biden administration will be possible. There is not enough time to do it. Providing the latest vaccines to combat what public health experts expect to see in the winter surge.
As a result, regulators may be forced to choose the latest vaccines based on data from laboratory tests and tests in mice and other animals rather than strong human tests. .. The situation can also be further complicated by the emergence of other new variants or subvariants by the fall.
The Food and Drug Administration’s external advisor Scheduled to meet on June 28th Discuss which vaccines are most effective as fall boosters. Vaccine makers say they need to start production immediately.
“Of course, the final decision is always left to the FDA,” said Dr. Fauci. “But what the FDA is likely to do is keep burning as much iron as possible, and they return to an alternative path of decision, laboratory data and possible animal data. You may need to. “
Asked if Americans would accept booster formulations without long human trials, he said, “People who are really very worried about protecting themselves will.”
John Moore, a virologist at Weill Cornell Medicine in New York, said many medical professionals are comfortable at this point in switching the pandemic to another model for coronavirus vaccine development. Federal health officials said the composition of the influenza vaccine each year has been modified to suit new variants with a minimum of new human testing.
Trial of Moderna, a vaccine targeting Omicron, began in late February. The average age of the participants was 57 years. All volunteers were vaccinated with Moderna’s existing vaccine three times, twice, and then boosted an average of eight months after the second.
Approximately four and a half months after the first booster, 377 volunteers received a second booster with an existing vaccine, and 437 received a booster designed to work against Omicron. The updated booster produced a stronger immune response between those who were previously infected and those who were not.
Overall, people with updated boosters had 59% higher levels of neutralizing antibodies than those with existing boosters, according to data released by Moderna.
Antibodies are the body’s first line of defense to prevent infection by the coronavirus. No other immune response was measured to protect against Covid-19. These tests are much more complex and time consuming.
Dr. Paul Burton, Moderna’s Chief Medical Officer, said the results are very promising. “I really feel that this is a kind of fundamental turning point in the fight against this virus, which means it can adapt to variants,” he said.
However, Dr. Moore said that less than double the increase in neutralizing antibodies compared to existing vaccines is “a small benefit.”
“Given the cost and logistics, and everything else involved, does that justify the switch of vaccine composition?” He asked. “That’s the subject of debate.”
Pfizer and its German partner BioNTech are also testing Omicron-specific vaccines and will announce the results shortly.
According to the company, in April, preliminary results were announced on a vaccine that was first detected in late 2020 and was modified to attack the beta variant. Also for Delta and Omicron variants. A Moderna official said the additional protection against Omicron lasted for six months, but said he hoped that an Omicron-specific vaccine would be a better candidate.
