RICHMOND, Va. - Virginia health officials said new data released by Pfizer showing that a third dose of the vaccine could strongly boost protection against the Delta variant was encouraging but added that more data needed to be obtained before further steps could be taken.
"I think it's really encouraging news that came out this morning," said VDH Division of Immunization Epidemiologist Marshall Vogt. "It looks like for the 18 to 55 group, there's about a five-fold increase in what we call neutralizing antibodies. And in adults 65 to 85, it was an 11-fold increase compared to just two doses."
Vogt said there could be advantages of a booster shot.
"What it would really do is continue to combat the issue that we might be starting to see now based on some of this data, which is waning immunity," said Vogt.
However, while that may be the case, he said Pfizer’s data for a third shot was still preliminary.
"It's very small numbers and a lot of the trials too. So I think this is encouraging news, but we need to see more data and really learn more about what Pfizer is thinking might be ideal. And then what FDA and CDC have to say.
He said that the question that remained was how the booster would come into approval.
"So, for instance, you know, the FDA, we need to look at this and either maybe amend the Emergency Use Authorization that exists already for Pfizer or issue a new Emergency Use Authorization."
While all of that still needed to be sorted out, Dr. Richard Wenzel, VCU Infectious Disease Epidemiologist, said there were arguments to move forward with a booster.
"If you take people who in the country have any kind of hematologic malignancies like leukemia or lymphoma, what we've seen in a few studies is only half of them develop antibodies after the second shot," said Dr. Wenzel. "The other thing we know, if you just look at who's getting the breakthroughs among the vaccinated people, 45% of them are over age 60."
Dr. Wenzel said they indicated to him that as people age, they may not develop the robust immune response that younger people develop.