From News Nation:
“COVID boosters targeting
newest variants cleared”
The U.S. on Wednesday authorized
its first update to COVID-19 vaccines, booster doses that target today’s most
common omicron strain. Shots could begin within days. The move by the Food and
Drug Administration tweaks the recipe of shots made by Pfizer and rival Moderna
that already have saved millions of lives. The hope is that the modified
boosters will blunt yet another winter surge. “You’ll see me at the front of
the line,” FDA vaccine chief Dr. Peter Marks told The Associated Press shortly
before his agency cleared the new doses.
Until now, COVID-19 vaccines have
targeted the original coronavirus strain, even as wildly different mutants
emerged. The new U.S. boosters are combination, or “bivalent,” shots. They
contain half that original vaccine recipe and half protection against the
newest omicron versions, called BA.4 and BA.5, which are considered the most
contagious yet. The combination aims to increase cross-protection against
multiple variants. “It really provides the broadest opportunity for
protection,” Pfizer vaccine chief Annaliesa Anderson told the AP. The updated
boosters are only for people who have already had their primary vaccinations,
using the original vaccines. Doses made by Pfizer and its partner BioNTech are
for anyone 12 and older while Moderna’s updated shots are for adults — if it
has been at least two months since their last primary vaccination or their
latest booster. They’re not to be used for initial vaccinations.
There’s one more step before a
fall booster campaign begins: The Centers for Disease Control and Prevention
must recommend who should get the additional shot. An influential CDC advisory
panel will debate the evidence Thursday — including whether people at high risk
from COVID-19 should go first. “As we head into fall and begin to spend more
time indoors, we strongly encourage anyone who is eligible to consider
receiving a booster dose with a bivalent COVID-19 vaccine to provide better
protection against currently circulating variants,” FDA Commissioner Dr. Robert
Califf said in a statement.
The U.S. has purchased more than
170 million doses from the two companies. Pfizer said it could ship up to 15
million of those doses by the end of next week. The big question is whether
people weary of vaccinations will roll up their sleeves again. Just half of
vaccinated Americans got the first recommended booster dose, and only a third
of those 50 and older who were urged to get a second booster did so. It’s time
for U.S. authorities to better explain that the public should expect an updated
COVID-19 vaccination every so often, just like getting a fall flu shot or a
tetanus booster after stepping on a rusty nail, said University of Pennsylvania
immunologist E. John Wherry. “We need to rebrand it in a societally
normal-looking way,” rather than a panicked response to new mutants, Wherry
said. “Give a clear, forward-looking set of expectations.”
Here’s the rub: The
original vaccines still offer strong protection against severe disease and
death from COVID-19 for most generally healthy people, especially if they got
that important first booster dose. It’s not clear just how much more benefit an
updated booster will bring — beyond a temporary jump in antibodies capable of
fending off an omicron infection.
One reason: The FDA
cleared the modifications ahead of studies in people, a step toward eventually
handling COVID-19 vaccine updates more like yearly flu shots. First, FDA
checked human studies of earlier Pfizer and Moderna attempts to update their
vaccines — shots matching the omicron strain that struck last winter. That
recipe change was safe, and substantially boosted antibodies targeting the
earlier variant — better than another dose of the original vaccine — while adding
a little protection against today’s genetically distinct BA.4 and BA.5 omicron
versions. But FDA ordered the companies to brew even more up-to-date doses that
target those newest omicron mutants instead, sparking a race to roll out shots
in less than three months. Rather than waiting a few more months for additional
human studies of that recipe tweak, Marks said animal tests showed the latest
update spurs “a very good immune response.” The hope, he said, is that a
vaccine matched to currently spreading variants might do a better job fighting
infection, not just serious illness, at least for a while.
What’s next? Even as
modified shots roll out, Moderna and Pfizer are conducting human studies to
help assess their value, including how they hold up if a new mutant comes
along. And for children, Pfizer plans to ask FDA to allow updated boosters for
5- to 11-year-olds in early October. It’s the first U.S. update to the COVID-19
vaccine recipe, an important but expected next step — like how flu vaccines get
updated every year. And the U.S. isn’t alone. Britain recently decided to offer
adults over 50 a different booster option from Moderna, a combo shot targeting
that initial BA.1 omicron strain. European regulators are considering whether
to authorize one or both of the updated formulas.
^ One step closer to getting this
ready before Fall. ^
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.