A team of the advisory panel of the US Food and Drug Administration (FDA) has voted to recommend Moderna booster COVID shot for emergency use authorization which will bring millions of people in the United States closer to being eligible for additional doses of COVID-19 shot.

The panel is called the Vaccine and Related Biological Products Advisory Committee, voted unanimously in favor of authorizing the shots.

However, the FDA is expected to make the final rulings in the next couple of days.

This is a follow-up on the recommended booster shots of Pfizer-BioNTech’s vaccines. Adults from the age of 65 and above who had received Mordena vaccines will also be eligible for a booster shot of the same vaccine while people in long-term care facilities and those between the age of 18 – 64 with underlying medical health conditions and those who at great risk of exposure to the coronavirus due to their jobs, will also get booster shots after 6 months.

The Moderna’s booster shot will also be given as a half-dose of 50 micrograms, unlike the full dose which is 100 micrograms.

Pfizer’s booster shot on the other hand will be a 30 microgram dosage as its initial series.

According to Mordena’s therapeutic area head for infectious diseases, Jacqueline Miller in her presentation to the committee, the company chose the half-dose because it wants to use the lowest dose possible needed to induce an immune response.

Miller also added that using a lower-dose booster has worked well for other vaccines such as DTaP vaccine which is able to protect people against tetanus, diphtheria, and whooping cough.

Unlike the previous month’s meeting about Pfizer’s booster shot whereby the panel rejected authorizing Pfizer booster dose for all adults within the age of 18 and above even though they might have been vaccinated six months earlier but limit the eligibility. The panel was less contentious with Moderna’s approach.

In a discussion after the vote, the panel largely agreed that boosters were not yet needed for the broader population, which would include all adults 18 and up.

The younger population appears to be responding quite well to the vaccines, and protection is holding up, said Dr. Michael Kurilla, an infectious disease expert with the National Institutes of Health. “I don’t necessarily see the need for a sort of ‘let it rip’ campaign for boosters for everyone who’s ever been vaccinated.”

FDA Panel and Mordena

According to data, protection from Moderna’s vaccine has waned. In this case, those who had received the company’s vaccine much earlier in the year were more likely to contract breakthrough infections unlike those who were vaccinated several months later – argued Miller.

Data also showed that almost all of the breakthrough infections were caused by the Delta variant.

Several of the breakthrough cases were considered severe, and two people died. 

“We are concerned about the breakthrough disease that we’ve been observing” in the participants in the original clinical trial, Miller said, “and particularly the breakthrough cases that we’re starting to see in severe disease in the older adults.”

The booster dose however has led to higher antibody levels and even antibodies against the delta variant.

About 20 cases of breakthrough infections were however reported among those who have received the booster shots.

According to the deputy director of the FDA’s division of vaccines, Dr. Doran FInk said that it,s still unknown the level of antibodies that are needed for full protection against the virus.

Moderna’s was able to convince the FDA which also red through the analysis to find that the booster shots were safe even though there have been several committee members that said they wanted to see more safety data from the company first.

There will however be side effects from the booster shots which will be similar to those that have been seen after the second dose. These include arm pain, fatigue, headache, and muscle aches.

Unlike the main vaccine campaign, the booster trial didn’t include as many participants to help evaluate if the extra dose raised the risk for myocarditis according to Fink.

Myocarditis is an inflammation of the heart muscle and has been linked to both Moderna and Pfizer’s Covid-19 vaccines.

Even though the condition is rare, it’s said to be most common in men under the age of 30.

An associate director for innovation in the FDA’s Office of Biostatistics and Epidemiology, Hui-Lee Wong said myocarditis occurred at similar rates following the second doses of both vaccines.

In data from Israel, where 3.7 million people have gotten Pfizer booster shots, 17 cases of myocarditis were reported, said Dr. Sharon Alroy-Preis, the director of public health services for Israel’s Health Ministry, who presented Thursday. 

“The rate of it is really, really low compared to what you would have expected if it was the same rate as after the second dose,” she said. “Perhaps it’s because we’re giving this dose five months or later” as opposed to giving two doses three weeks apart.

Another meeting will be convened about a booster shot of the Johnson & Johnson Covid vaccine and the body will also review the results of a National Institutes of Health study of “mixing and matching” Covid vaccines.

The study found that giving people who initially received the Johnson & Johnson (J&J) vaccine booster doses of either Pfizer’s or Moderna’s vaccine led to a stronger immune response than a second Johnson & Johnson dose.

And by next week, another group of advisers to the U.S. Centers for Disease Control and Prevention will accept the question of who should receive the Moderna and J&J booster shots

If the boosters are recommended, the CDC director, Dr. Rochelle Walensky, would then sign off, and the booster shots should be deployed to eligible recipients.