Are Moderna, J&J boosters needed?
Data unclear as FDA committee weighs in
A federal advisory committee will meet for two days this week to discuss the safety and need for a booster shot for people who received Moderna’s or Johnson & Johnson’s COVID-19 vaccine.
It won’t have much J&J data on which to base its decision.
Information posted by the Food and Drug Administration on Wednesday showed that about 8,000 people were studied after receiving a second dose of J&J’s vaccine two months after their first, and only 17 were tracked after getting a second shot at six months.
It isn’t clear if the data will be sufficient for the FDA panel, called the Vaccines and Related Biological Products Advisory Committee, to approve a second shot of J&J.
“The hope was that we would get a resolution of these issue and that J&J would get their emergency use authorization for a booster,” said Dr. William Schaffner, medical director for the National Foundation for Infectious Diseases. “Now things have gotten a little more complicated.”
Booster doses of the Pfizer-BioNTech vaccine, given to more than 230 million Americans since December, were approved last month for people over 65, as well as younger people whose medical conditions or jobs put them at higher risk for disease.
About 15 million Americans have received the J&J shot, compared with 153 million who’ve gotten Moderna. Roughly 8.5 million have received a third dose of the Pfizer-BioNTech vaccine since it was authorized in August for people who are immunocompromised and in September for people at higher risk for a severe COVID-19 outcome.
The Centers for Disease Control and Prevention said people should get repeat doses of the same vaccine they got originally, though the FDA advisory panel is scheduled to hear Friday about a small study that looked at the safety and effectiveness of getting a different
vaccine as a follow-up.
Data is clearer for Pfizer-BioNTech, because most of Israel’s population of 9.2 million people received that vaccine this year and have been carefully tracked.
The country offered booster shots to everyone this summer after data suggested vaccine protection against infection was fading.
Thursday and Friday, the FDA panel will have to consider smaller-scale data, which suggests the Moderna vaccine is following a similar, though perhaps slower, trajectory to Pfizer-BioNTech’s.
The Moderna and Pfizer-BioNTech vaccines are both based on mRNA technology.
In a follow-up study of participants from a research trial, Moderna found that a third shot, with half the dose of the first two, provided a major immune boost. Levels of so-called neutralizing antibodies had waned before the booster, which was given about six months after the second shot.
The third shot brought antibody levels in people of a variety of ages and health conditions above where they had
been after the second shot, according to the company’s study, which was released last month but has not been independently reviewed.
In another Moderna study conducted this summer as the delta variant of the coronavirus surged, participants who got two doses of the active vaccine 13 months earlier were compared with those who got the shots eight months earlier.
In the analysis, there were 88 cases of COVID-19 in those who were in the more recently vaccinated group, compared with 162 cases in those vaccinated last year. Nineteen people saw severe infections.
Neither study has been reviewed by independent experts.
J&J, which was initially given as a single shot, may need a second dose to provide better long-term protection, data from the company shows. Initial trial data showed the single shot protected against more than 70% of infections in the U.S. and nearly 100% of deaths.
In documents posted Wednesday, J&J said additional shots might be given two to six months after the initial dose, depending on the risk category and the strength of the immune response.
The safety data for people receiving an additional dose of J&J was good. According to the FDA, the vaccine would “still afford protection against severe COVID-19 disease and death,” although less so than the Pfizer-BioNTech and Moderna mRNA-based vaccines.
In a study released last month, J&J found that a second dose given two months after the first provided 94% protection against moderate-to-severe COVID-19 symptoms. A booster dose given six months after the single shot provides even more protection, the company said.
VRBPAC and a similar independent advisory group to the CDC decided last month not to recommend booster doses to everyone because of unclear need and the possibility of rare side effects.
Both groups said they might reconsider a recommendation as more data becomes available about the long-term effectiveness of the vaccines in the general population.