Pfizer’s RSV vaccine shows potential to protect high-risk adults ages 18-59, widening possible use

A

vaccine
from


Pfizer
showed
the
potential
to
protect
adults
ages
18
to
59
who
are
at
increased
risk
of
getting

severely
sick
from

respiratory
syncytial
virus
in
a
late
stage
clinical
trial,
the
company
said
Tuesday.

The
initial
data
suggests
that
Pfizer’s
shot,
known
as
Abrysvo,
could
help
protect
a
far
wider
population
from
RSV.
The
jab
is
currently
approved
in
the
U.S.,
Europe,
Japan
and
other
countries
for
adults

ages
60
and
older
and

expectant
mothers
who
can
pass
on
protection
to
their
fetuses. 

But
there
are
no
RSV
shots
approved
worldwide
for
younger,
high-risk
adults. 

RSV
causes

thousands
of
hospitalizations
and
deaths
among
older
Americans
and
hundreds
among
infants
each
year.
The
virus
can
also
cause
severe
illness
in
younger
adults
with
weakened
immune
systems
or
underlying
chronic
conditions
such
as
asthma
and
diabetes.

Nearly
10%
of
U.S.
adults
ages
18
to
49
have
a
chronic
condition
that
puts
them
at
risk
of
severe
RSV
disease,
according
to
Pfizer.
That
number
rises
to
around
24%
for
those
aged
50
to
64. 

“I
think
about
my
own
family
and
my
friends
who
have
asthma
or
were
carrying
conditions
from
childhood,”
Dr.
Iona
Munjal,
Pfizer’s
executive
director
of
clinical
vaccine
research
and
development,
told
CNBC. “That
population
is
at
risk
of
getting
RSV
every
single
winter
…
over
and
over
again.
There’s
no
durable
immunity
without
vaccination.”

Munjal
added
that
high-risk
adults
aged
18
to
59
are
the “next
logical
step”
after
working
to
drop
rates
of
RSV
disease
in
older
populations. 

The
data
comes
as
Pfizer
tries
to
win
more
share
of
the
RSV
market
after
lagging
behind


GlaxoSmithKline
last
year.
GSK’s
RSV
vaccine
for
adults
ages
60
and
above
booked
around
£1.2
billion
($1.5
billion)
in
sales
last
year.
Meanwhile,
Pfizer’s
shot
recorded
about
$890
million
in
revenue
in
2023. 

Pfizer
said
it
plans
to
submit
the
data
to
regulatory
agencies
and
file
for
an
expanded
approval
of
Abrysvo
for
ages
18
and
up.
The
company
did
not
provide
any
details
on
the
timeline
for
those
plans. 

Pfizer
also
intends
to
present
final
results
from
the
trial
at
an
upcoming
scientific
conference
and
submit
them
for
publication
in
a
peer-reviewed
journal. 

Pfizer
said
Tuesday
its
vaccine
met
the
phase
three
trial’s
main
goals
for
efficacy
and
safety
in
high-risk
adults
ages
50
to
59. 

The
company
specifically
released
data
on
a
sub-study
examining
nearly
700
patients
who
are
at
high
risk
of
severe
RSV
due
to
underlying
medical
conditions.
Pfizer
expects
to
release
data
on
another
sub-study
on
roughly
200
patients
with
weakened
immune
systems
later
this
year,
Munjal
told
CNBC. 

A
single
dose
of
the
drugmaker’s
shot
elicited
an
immune
response
against
RSV
A
and
RSV
B,
which
are
the
two
major
subtypes
of
the
virus,
according
to
the
results. 

The
immune
response
was
similar
to
that
observed
in
adults
60
and
above.
Previous
late
stage

research
on
more
than
30,000
adults
in
that
older
age
group
found
that
Pfizer’s
shot
maintained
protection
against
RSV
across
two
full
seasons
of
the
virus. 

“The
level
of
antibodies
that
you
see
after
vaccination
in
those
who
are
18
to
60
are
similar
to
those
who
are
60
and
up,”
Munjal
told
CNBC.
She
later
added
that
it “gives
you
confidence
that
across
those
two
populations,
they’re
actually
responding
to
vaccine
the
same,
and
therefore
are
likely
to
have
a
similar
efficacy.” 

Participants
also
saw
a
fourfold
increase
in
their
levels
of
protective
antibodies
against
RSV
A
and
RSV
B
one
month
after
they
received
Pfizer’s
shot
compared
to
before
vaccination. 

The
company
said
patients
tolerated
the
vaccine
well
in
the
trial.
Safety
data
in
high-risk
adults
ages
18
to
59
was
consistent
with
the
results
in
adults
60
and
above,
Pfizer
added. 

GSK
released

late
stage
trial
data
in
October
suggesting
that
its
shot
could
protect
adults
ages
50
to
59. 

The
Food
and
Drug
Administration
in
February

granted “priority
review”
to
GSK’s
application
to
expand
approval
of
its
drug,
Arexvy,
to
that
new
age
group.
That
designation
speeds
up
the
review
process
for
certain
drugs
for
serious
conditions. 

The
FDA
is
expected
to
decide
whether
to
approve
GSK’s
RSV
vaccine
for
adults
ages
50
to
59
on
June
7.