While U.S. health officials, some other countries and vaccine makers
have said boosters are needed, many scientists and vaccine experts
The FDA staff said in documents
prepared for the committee this week that the vaccine Pfizer Inc
developed with Germany's BioNTech SE is still very effective at
preventing severe illness and death and that the evidence is mixed
on whether its efficacy declines over time.
Pfizer, which is arguing for broad use of a third shot, submitted
data from an analysis of over 300 participants in its late stage
clinical trial showing that the vaccine's efficacy diminished by
around 6% every two months after the second dose, and that an
additional shot boosted immunity.
The FDA's Vaccines and Related Biological Products Advisory
Committee will also consider data from Israel, which has been
administering booster doses of the Pfizer/BioNTech vaccine.
The effectiveness of the second dose of the vaccine waned six months
after administration, making a booster necessary, Israeli health
officials had said.
It began offering a COVID-19 booster https://www.reuters.com/world/middle-east/israel-offers-covid-19-booster-shots-all-vaccinated-people-2021-08-29
to people as young as age 12 last month, expanding a campaign that
began in July for people over 60.
A new analysis by Israeli scientists published on Wednesday in the
New England Journal of Medicine found that among 1.1 million people
age 60 or older who had been fully vaccinated at least 5 months
earlier, those who received a booster were less likely to be
infected or become severely ill than those who did not get the third
The booster debate gained urgency as U.S. COVID-19 hospitalizations
and deaths surged due to the highly transmissible Delta variant of
the virus, mostly among the unvaccinated. But infections among fully
vaccinated people have risen and they can spread the virus on
occasion, mostly to unvaccinated people.
Recent polls have shown most vaccinated Americans want a booster to
enhance their protection.
'LARGER POPULATIONS MAY TAKE LONGER'
Wall Street analysts see the additional shots ultimately getting
approved for a broad population.
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"We expect a potential positive
FDA support for boosters for elderly ahead of
Biden's rollout, but larger populations may take
longer for broad support and approval,"
Jefferies analyst Michael Yee said in an email.
Scientists say the strongest evidence for
boosters is for older adults and other high risk
"My guess is we are
going to end up with a recommendation for booster doses for a
certain subpopulation, such as adults older than 65," said Bill
Moss, executive director of the International Vaccine Access Center
at the Johns Hopkins Bloomberg School of Public Health.
More than 1.9 million Americans have already gotten a booster dose
after the government authorized them for people with compromised
immune systems, according to the U.S. Centers for Disease Control
and Prevention (CDC).
Eight top health officials in the Biden Administration - including
the heads of the FDA and the CDC - said in August they believe
booster shots will be needed because emerging data shows that
protection against COVID-19 decreases over time.
It is planning a booster campaign for the week of Sept. 20,
contingent on backing by the FDA and CDC.
An FDA decision on a booster will come after the committee
recommendation. Advisers to CDC will meet next Wednesday and
Thursday after which the agency's director, Rochelle Walensky, will
decide whether to follow their advice.
Moderna Inc has also asked for approval of a booster and released
data on Wednesday
showing that protection from its vaccine also wanes over time. That
is not expected to be discussed at Friday's meeting.
(Reporting by Manojna Maddipatla and Ankur Banerjee in Bengaluru;
Editing by Caroline Humer and Bill Berkrot)
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