SAN DIEGO (KGTV) -- Americans who got the Johnson & Johnson COVID vaccine will likely need a booster dose, but the nation’s top health officials said they were still waiting on additional data before finalizing if and when those doses should be administered.
The Biden Administration announced Wednesday that recipients of the Pfizer and Moderna vaccines will be eligible for a third shot beginning September 20. Those boosters will be offered on a rolling basis to people eight months after their second dose.
However, health officials delayed making a similar announcement for the 14 million Americans who got the J&J vaccine.
“It's a little disappointing to see them being left behind,” said Dr. Shane Crotty, a professor at the La Jolla Institute for Immunology.
More than 150 million Americans have now gotten the two-dose Pfizer or Moderna vaccines, which use mRNA technology. J&J uses technology similar to the vaccine from AstraZeneca: an adenovirus vector.
Federal health officials said they were waiting for more data on J&J before rolling out a booster plan, but they did not specify what data they were waiting on.
Johnson & Johnson has not yet released results from a large clinical trial on a two-dose regimen that began last year. Additionally, real-world data on J&J’s efficacy against the delta variant has been slim.
“I think we need to recognize the Johnson & Johnson vaccine was over two months behind the mRNA vaccines in terms of its data and when we started to vaccinate people,” said CDC Director Dr. Rochelle Walensky. “It shouldn’t be a surprise that we are a little behind in the data there.”
Dr. Crotty said all three vaccines have performed extraordinarily well against severe disease, but said there has been a disappointing lack of data on how well J&J has performed in the U.S. since the delta variant became dominant.
A study in South Africa of nearly 500,000 healthcare workers released this month found one dose of J&J was 71 percent effective against hospitalization from delta, down from 100 percent in the company’s clinical trial. The authors released a preview of the findings and did not say how well the vaccine prevented disease in general.
“That's not the range we want to be in for preventing those severe outcomes,” said Crotty, who noted that several studies show the mRNA vaccines remain more than 90 percent effective against hospitalization.
Three new studies from the CDC suggest the strength of the mRNA vaccines begins to wane after several months, with the effectiveness against symptomatic infection dropping from 95 percent to about 80 percent. The mRNA vaccines were about 55 percent effective against all infections regardless of symptoms in the three groups the CDC examined.
That suggests the J&J shot, which was 72 percent effective in the U.S. before the delta variant, may also be less effective now at preventing mild infections, Crotty said. J&J produces fewer antibodies than the mRNA vaccines, he noted.
A second shot of J&J nearly tripled antibody levels with no increase in side effects, according to early results from the company’s clinical trial. The final Phase 3 leg of the trial has not yet been published.
“You need to make a decision before things are a problem,” Crotty said. “I’m hoping that means they think there will be J&J data in the next week or something and they’re just going to wait for that. Because I don’t think it would make sense to wait for a month.”
Some cities aren’t waiting. The health department in San Francisco is allowing people who got J&J to get a second shot, provided they talk to their doctor about it first.