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Cannabis
compound
CBD
stops
coronavirus
in test
tube,
but can
it treat
COVID?
reuters.com
A
marijuana
leaf is
displayed
at Canna
Pi
medical
marijuana
dispensary
in
Seattle,
Washington,
November
27,
2012.
REUTERS/Anthony
Bolante/File
Photo
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to
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Early
research
suggesting
that a
popular
non-psychoactive
compound
derived
from
marijuana
might
help
prevent
or treat
COVID-19
warrants
further
investigation
in
rigorous
clinical
trials,
researchers
say.
Several
recent
laboratory
studies
of
cannabidiol,
or CBD,
have
shown
promising
results,
attracting
media
attention.
However,
many
other
potential
COVID
treatments
that
showed
promise
in test
tubes,
from
hydroxychloroquine
to
various
drugs
used to
treat
cancer
and
other
diseases,
ultimately
failed
to show
benefit
for
COVID-19
patients
once
studied
in
clinical
trials.
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to
Reuters.com
Marsha
Rosner
of the
University
of
Chicago
led a
team
that
found
CBD
appeared
to help
curb
SARS-CoV-2
in
infected
cells in
laboratory
experiments.
"Our
findings
do not
say this
will
work in
patients.
Our
findings
make a
strong
case for
a
clinical
trial,"
she
said.
Using
small
doses of
highly
purified
CBD that
approximate
what
patients
receive
in an
oral
drug
already
approved
for
severe
epilepsy,
Rosner
and
colleagues
found
that CBD
did not
keep the
coronavirus
from
infecting
cells in
test
tubes.
Rather,
it acted
soon
after
the
virus
entered
the
cells,
blocking
it from
making
copies
of
itself
in part
via
effects
on the
inflammatory
protein
interferon.
They
found
similar
effects
in
infected
mice,
according
to a
report
in
Science
Advances.
When
they
looked
at a
group of
adults
with
severe
epilepsy,
the
researchers
found
those
who were
taking
the
approved
CBD drug
had
lower
rates of
COVID-19.
But a
backward
look at
a small
number
of
patients
does not
yield
conclusive
information.
Only
randomized
clinical
trials
can do
that,
Rosner
said.
"I
know my
message
is not
something
people
want to
hear,"
she
said.
Small
doses of
tetrahydrocannabinol
(THC) -
the
marijuana
ingredient
that
causes
the high
-
cannabidiolic
acid
(CBDA),
cannabidivarin
(CBDV),
cannabichromene
(CBC),
and
cannabigerol
(CBG)
did not
keep the
virus
out of
cells or
prevent
it from
replicating,
her team
found.
"Not
only did
THC not
work,
but
combining
it with
CBD
prevented
CBD from
working,"
Rosner
said.
NO
COVID
CURES AT
CBD
DISPENSARY
A
separate
team
reported
recently
in the
Journal
of
Natural
Products
that
high
doses of
CBG and
CBDA do
prevent
the
coronavirus
from
breaking
into
cells.
Richard
van
Breemen
from
Oregon
State
University
told
Reuters
that the
doses
his team
tested
were
non-toxic
to
cells.
It is
not
clear
yet that
similarly
high
doses
would be
safe for
humans,
his team
said.
"You
want the
lowest
possible
effective
dose,"
Rosner
said,
because
of
potential
side
effects
as the
drug is
filtered
through
the
liver.
The
CBD her
team
tested
was more
than 98%
pure,
while
purity
in
commercial
products
is far
lower.
"People
should
not run
out and
get CBD
from
their
favorite
dispensary,"
she
said.
CBD
products
have
become
widely
available
in many
forms
and have
been
touted -
often
without
proof
from
clinical
trials -
as
treatments
for pain
and
other
ailments.
Small
CBD
trials
in
humans
with
COVID-19
are
underway.
In
one
completed
study,
researchers
in
Brazil
randomly
assigned
105
patients
with
mild or
moderate
COVID-19
to
receive
CBD or a
placebo
for 14
days
along
with
standard
care.
The CBD
had no
apparent
effect,
according
to an
October
report
in
Cannabis
and
Cannabinoid
Research.
In a
proof-of-concept
study at
Sheba
Medical
Center
in
Israel,
researchers
are
randomly
assigning
patients
with
mild
COVID to
receive
CBD or a
placebo.
An
early-stage
trial at
Rabin
Medical
Center,
also in
Israel,
aims to
test the
effect
of CBD
in
severely
or
critically
ill
patients.
However,
study
leader
Dr.
Moshe
Yeshurun
told
Reuters
that
accruing
participants
has been
difficult
because
the
current
Omicron-driven
coronavirus
wave
"consists
mostly
of
patients
with
mild to
moderate
disease."
Rosner's
team is
exploring
the
possibility
of a
clinical
trial
that
would
likely
focus on
asymptomatic
or mild
cases of
COVID.
Meanwhile,
she is
concerned
that
media
reports
overstating
the
potential
of
cannabinoids
will
lead
people
to
self-medicate
with
CBD,
stop
using
masks
and
avoid
vaccines.
"We
would
love to
be able
to say
specifically"
that a
certain
dose of
cannabinoids
is
helpful,
she
said,
but at
this
point,
"vaccine-induced
antibodies
and
antibody
drugs
are much
more
effective
at
blocking
infection."
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Reuters.com
Reporting
by Nancy
Lapid;
Editing
by
Michele
Gershberg
and Bill
Berkrot
Our
Standards:
The
Thomson
Reuters
Trust
Principles.
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