Are COVID-19 booster injections variant-specific?

key takeaways

  • The U.S. Food and Drug Administration (FDA) and Centers for Disease Control and Prevention (CDC) have authorized booster doses for all persons 12 years of age and older in the United States
  • A second mRNA booster dose is now approved for certain individuals at increased risk for severe COVID-19 disease.
  • Pfizer and J&J’s booster doses will be the same as the initial vaccine, while Moderna’s will be half the dose.
  • Currently, the vaccine has the same ingredients as the original series. Although Pfizer and Moderna are exploring this option, no vaccines have been altered to better target COVID-19 variants.

A COVID-19 booster shot began in late September for some vaccinated people, but only in select groups of people at increased risk of COVID-19 exposure or serious illness. As of November 2021, all three vaccines — Moderna, Pfizer and Johnson & Johnson — are approved for booster immunizations.

Soon after, the FDA authorized booster doses for all adults who completed the initial COVID-19 vaccine series. The agency then expanded eligibility for the Pfizer booster to teens between the ages of 12 and 17.

The CDC now recommends that all people age 12 and older use a COVID-19 booster:

  • Completed a Pfizer or Moderna lead vaccine series at least five months ago.
  • Got the Johnson & Johnson vaccine at least two months ago.

According to the CDC, eligible adults can choose any authorized COVID-19 booster. However, individuals are now advised to get the Pfizer or Moderna mRNA COVID-19 vaccine rather than the J&J vaccine due to concerns about blood clotting side effects. The J&J vaccine remains an option for those who are unable or unwilling to get a different vaccine.

Teens ages 12 to 17 who complete the Pfizer Junior Series are only eligible for Pfizer Boosters.

Pfizer and Johnson & Johnson’s boosters will use the same dose as the initial vaccine, while Moderna’s dose will be half that (50 micrograms).

A third dose of Pfizer-BioNTech and Moderna’s vaccine has been authorized by the U.S. Food and Drug Administration (FDA) for use in immunocompromised people who meet certain criteria.

The agency also authorized additional mRNA booster doses for certain high-risk individuals.

A second booster dose is now recommended for people 12 years of age and older with certain immunocompromised conditions and for all adults 50 years and older who received the first booster dose at least four months earlier.

While vaccine makers are developing and testing the next generation of COVID-19 vaccines to provide better protection against variants of the virus, for now, the booster shots are no different from the vaccines people are already familiar with.

Dr. Philip Felgner, director of the Center for Vaccine Development at the University of California, Irvine, told VigorTip that the booster will be “exactly the same” as a first-time vaccinated person when it comes to the makeup of the vaccine. vaccine.

Same shot, different day

In August, the FDA authorized a third dose of the vaccine for immunocompromised individuals 12 years of age and older who meet certain criteria. The authorization was later expanded to include children five years of age and older.

Shortly after the FDA authorized a third dose of the mRNA vaccine for immunocompromised people, President Biden announced a potential booster program that would begin as early as Sept. 20 for other vaccinated people.

The White House initially said a person could get a booster dose eight months after being fully vaccinated — pending FDA authorization for the booster dose.

Currently, FDA and CDC have authorized booster shots for all three COVID-19 vaccines in the U.S.

Whether someone receives a third dose of the vaccine as an immunocompromised person or a booster dose based on when the last vaccination was given, the vaccines will be the same formula that people had previously received, Fergner said. Pfizer-BioNTech applied for authorization for a booster injection at the same dose as the original vaccine, while Moderna’s booster application was a 50-microgram dose—half the initial dose.

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Third dose and booster

The Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices (ACIP) has clarified the difference between a third dose of vaccine and a booster shot.

The CDC states that “additional doses are indicated for individuals who may not respond adequately to the initial two-dose regimen, particularly those who are moderately to severely immunocompromised.”

In a statement issued Sept. 2, Kristen Nichols, PharmD, BCPS, BCPPS, BCIDP, senior content management consultant for pediatric infectious diseases at Wolters Kluwer, defined a booster shot as “given to those who may have an adequate initial response but who are immune May weaken over time.”

Nichols clarified that the booster is for “typically healthy people who were initially vaccinated but now need to ‘reactivate’ this protection.”

Are boosters common in vaccines?

Addressing Variation with Vaccines

While the boosters are more of the same, we may see an updated COVID vaccine in the future. “The technology is very flexible,” Felgner said. “They’ll be able to change or modify it and then make next-generation versions as the virus mutates.”

In a press release, Pfizer-BioNTech announced that it is currently developing a COVID vaccine “targeting the Delta variant of the full spike protein.” The updated version still needs to be thoroughly tested and reviewed, and clinical trials are underway.

The new vaccine is not part of the White House’s boosted rollout plan, and the update may not be called a “boost” vaccine.

“If we’re as close to a new COVID vaccine for a variant as we are with a seasonal flu shot, it doesn’t necessarily have a specific term,” Nichols said. New strains are incorporated into flu vaccines each year, depending on which ones The strain is expected to appear in influenza vaccines. There is an epidemic, and we continue to call it the flu shot. “

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Will boosters work on variants?

Early data on booster doses for the Pfizer-BioNTech and Moderna vaccines are promising, but there are still some unknowns as virus variants continue to emerge.

Pfizer and BioNTech submitted early clinical trial data to the FDA. In the trial, participants received a booster injection eight to nine months after the second dose.

According to the press release, the results showed that the third dose “elicited significantly higher levels of neutralizing antibodies” against the original SARS-CoV-2 strain as well as the Beta and Delta variants.

Moderna has also initiated a data submission process for early clinical trial data. For the phase 2 clinical trial, participants received a booster dose six months after getting the second dose. The booster showed a “robust antibody response against the Delta variant,” Moderna CEO Stéphane Bancel said in a press release.

Omicron is a worrying new variant that contains more mutations than previous strains and is thought to spread more easily than the wild-type virus. According to the CDC, the current COVID-19 vaccine is expected to prevent serious illness, hospitalization and death from Omicron infection.

Data from preliminary studies conducted by Pfizer showed that three doses of Pfizer’s vaccine neutralized the Omicron variant, while two doses were significantly less protective.

Similarly, another current study (not yet peer-reviewed) showed that those who received booster doses of mRNA vaccines (Moderna or Pfizer) had a strong cross-neutralizing response to Omicron, whereas those who received mRNA vaccines detected a strong cross-neutralizing response to Omicron No neutralization reaction. Only the primary vaccination series was completed.

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As boosters start rolling out to people who have already been vaccinated, it is important for those who have not been vaccinated to start their first dose of the vaccine.

“Even with such an aggressive Delta variant, this vaccine is very effective,” Felgner said. “It protects against the worst coronavirus infections.”

what does this mean to you

If you are over 12 years old and:

  • Completed a COVID-19 mRNA vaccination series at least five months ago.
  • Got the Johnson & Johnson vaccine at least two months ago.

People 50 and older who received a booster shot at least four months ago are now eligible for a second booster shot.

If you are immunocompromised, talk with your healthcare provider about receiving additional doses.

The information in this article is current as of the date listed, which means that you may have updated information as you read this article. For the latest updates on COVID-19, visit our Coronavirus news page.