Three reports published Wednesday support the argument that people may need a booster dose of Pfizer’s Covid-19 vaccine over time, and suggest such boosters would be safe. The reports are part of a batch of data that will be discussed Friday by vaccine advisers to the US Food and Drug Administration. The FDA is considering a request by Pfizer to approve a third, booster dose of its vaccine for most people six months after they get their first two doses of vaccine.
While the FDA clearly signaled it would grant emergency use authorization (EUA) to Pfizer’s and Moderna’s vaccines last December as well as granting EUA to Johnson & Johnson’s vaccine in February along with fully approving Pfizer’s vaccine last month, it was notably neutral about the question of booster doses for the general public. There are “many potentially relevant studies, but FDA has not independently reviewed or verified the underlying data or their conclusions,” it said in a briefing document released Wednesday ahead of the meeting of its Vaccines and Related Biological Products Advisory Committee.One of the reports is the formal presentation of data from Israel released earlier this month that showed booster doses of the vaccine not only raised immunity as measured in the blood but also showed a real-world reduction in infection. Two others, sponsored by Pfizer, support the argument that immunity, as measured in the blood, does begin to wane over time after people get both initial doses. One shows a booster restores that immunity.
— Meg Tirrell (@megtirrell) September 15, 2021
The reports, all published in the New England Journal of Medicine, are being used by Pfizer and by some federal officials to support the argument that most people will need booster doses starting around six months after they are initially vaccinated. One Pfizer-led study reports on the ongoing trial of more than 40,000 volunteers. “Through six months of follow-up and despite a gradual decline in vaccine efficacy, BNT162b2 (Pfizer’s vaccine) had a favorable safety profile and was highly efficacious in preventing Covid-19.
The @Pfizer @US_FDA booster documents https://t.co/KMb2pfKLAv
reviews all data on effectiveness (VE) vs infection
—waning immunity not related to Delta, just a matter of time, 6% reduction of VE every 2 months
—restoration to 95% VE by 3rd shot
—recommends booster for all age 16+ pic.twitter.com/CO5EqVON5v
— Eric Topol (@EricTopol) September 15, 2021
Two other studies make a stronger case for boosters. One, from Israel, was reported as a pre-print in early September. Separately, vaccine maker Moderna released some data on waning immunity and booster doses of its Covid-19 vaccine Wednesday. One Moderna-led team reported interim data covering 80 volunteers in an ongoing trial who got booster doses of Moderna’s currently authorized vaccine, or of vaccines re-formulated to match the Beta variant, the Gamma or P.1 variant, or the Delta variant. Moderna also said it had data showing immunity wanes for its vaccine, too, months after people complete the two-dose series.
A new study out of Israel found COVID booster shots lowered risk of severe illness in people over 60 by nearly 20 times — and now, the FDA is discussing whether Pfizer vaccine boosters are necessary for the public. pic.twitter.com/rk6iYJ4sfS
— CBS Mornings (@CBSMornings) September 16, 2021
Moderna is also in the process of asking the FDA to authorize booster doses of its vaccine.