The actions taken by the FDA set differing availability of the 3 emergency-authorized vaccines.
The US Food and Drug Administration (FDA) expanded patient eligibility for COVID-19 vaccine booster doses while also announcing the emergency use authorization (EUA) of Moderna's and Janssen's vaccine boosters on Wednesday.
With the decision, the following patients are newly eligible for booster doses with the following emergency-authorized or approved vaccines:
BNT162b2 (Comirnaty) from Pfizer-BioNTech
mRNA-1273 from Moderna
Janssen COVID-19 Vaccine, from Janssen (Johnson & Johnson)
Each of the vaccines are now available as a heterologous booster dose in eligible individuals—meaning that person do not need to receive a booster dose consistent with what they received as their primary COVID-19 vaccination. Individuals seeking booster doses with the mRNA vaccines from Pfizer-BioNTech and Moderna must be ≥6 months removed from completion of their primary vaccine series; individuals seeking a Janssen booster dose must be ≥2 months removed.
This decision comes after the Vaccine and Related Biological Products Advisory Committee (VRBPAC) unanimously voted to recommend the FDA grant Moderna and Janssen an EUA to administer booster doses on Thursday and Friday of last week.
The heterologous “mixing and matching” advisory comes after a clinical trial showed the practice can actually increase immune response, published and discussed by FDA advisors last week.
Before this decision, Pfizer-BioNTech was the only vaccine able to administer booster under EUA. Two doses of the Pfizer-BioNTech vaccine wane in efficacy after 6 months, making its boosters a high priority.
The VRBPAC voted to support the benefit of third shot of Moderna at half the dosage, though Moderna’s booster trial gave participants a full third dose.
Unlike the mRNA vaccines, a second dose of the Janssen vaccine was given support from the advisory committee for eligible adults, due to its lower initial vaccine efficacy of 75%.
Some experts looked at the waning of the Janssen vaccine as an indication that it should be initially administered in 2 doses, rather than 1 dose and then a supplement 2-6 months later.
There are concerns regarding booster doses; some experts believe the doses should be dispersed nationally and internationally to immunize individuals not yet vaccinated, thus increasing global population immunity.
However, the VRBPAC panel noted that many Americans are receiving homologous and heterologous booster doses already, so they advised the FDA act quickly and make an official decision. As the public worries about waning immunity and breakthrough infections become more common among vaccinated individuals, most experts are in full support of the decision.
The Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP) will convene Thursday to set recommendations for COVID-19 vaccine booster doses, after which rollout would begin.
In an interview with Contagion, Donald Alcendor, PhD, Assistant Professor of Cancer Biology at Meharry Medical College and Adjunct Associate Professor of Cancer Biology at Vanderbilt University School of Medicine, emphasized the significance of the news for the US population that was awaiting booster doses: the 69 million individuals vaccinated with mRNA-1273 and 15 million vaccinated with Janssen COVID-19 Vaccine who were eligible at the time of the Pfizer-BioNTech EUA but “had no option for the added protection of a booster.”
“I expect the FDA (authorization) and CDC guidance for the Moderna and Johnson & Johnson booster will be forthcoming,” Alcendor said. “The boosters for Johnson & Johnson will not be limited as the Pfizer and Moderna boosters, but will include all individuals that receive the single-shot Johnson & Johnson vaccine.”
Carlos del Rio, MD, Executive Associate Dean of Emory School of Medicine & Grady Health System, echoed support for the greater booster dose availability and expanded eligibility.
“Not everyone needs the booster, and at least the Pfizer authorization was very clear that some people should get a booster and some people may get a booster,” del Rio said. “I think the “should” group—the older individuals, those with immunodefiency—I’m really glad all those who had been vaccinated with Moderna are now going to get that information.”
William Schaffner, MD, Professor of Preventive Medicine at Vanderbilt University Medical Center, discussed the health care community’s need for better defined booster eligibility—a distinction that comes with FDA regulation.
“It’s time,” Schaffner said. “We’re ready for them, the public is ready for them, and providers are ready to recommend and give them.”