"The single remaining monoclonal
antibody therapy effective against the variant is now in short supply in the
U.S., imperiling an option that doctors and hospitals have relied on.
Hospitals, drug companies and Biden
administration officials are racing to address one of the Omicron variant’s
biggest threats: Two of the three monoclonal antibody treatments that doctors
have depended on to keep Covid-19 patients from becoming seriously ill do not
appear to thwart the latest version of the coronavirus.
The one such treatment that is still
likely to work against Omicron is now so scarce that many doctors and hospitals
have already run through their supplies.
Monoclonal antibodies have become a
mainstay of Covid treatment, shown to be highly effective in keeping high-risk
patients from being hospitalized. But even as infections surge and Omicron
becomes the dominant form of new cases in the United States, some hospitals
have begun scaling back the treatments, fearing they have become suddenly
useless.
In New York, hospital administrators
at NewYork-Presbyterian, N.Y.U. Langone and Mount Sinai all said in recent days
that they would stop giving patients the two most commonly used antibody
treatments, made by Eli Lilly and Regeneron, according to memos obtained by The
Times and officials at the health systems.
“This is a dramatic change just in
the last week or so,” said Dr. Daniel Griffin, an infectious disease specialist
at Columbia University in New York. “And I think it makes sense.”
The Omicron variant accounted for an
estimated 73 percent of new cases in the United States last week, according to the
Centers for Disease Control and Prevention. That’s up from just over 12 percent
the week before.
(Some researchers think the
percentage is not yet that high, although they also find Omicron infections
doubling every two or three days.)
Federal health officials plan to
assess at the end of this week whether to pause shipments of the Eli Lilly and
Regeneron products to individual states, based on how dominant Omicron becomes
in different regions of the country, according to a senior administration
official who spoke on condition of anonymity.
The one monoclonal antibody
treatment that has performed well against Omicron in laboratory experiments
is also the most recently authorized:
sotrovimab, made by GlaxoSmithKline and Vir Biotechnology and cleared in May.
Already in high demand even before
Omicron arose, the supply of sotrovimab is very limited for now. But the
situation is likely to improve somewhat in the coming weeks. The Biden
administration is in talks with GlaxoSmithKline about securing more doses to be
delivered by early next year, the administration official said.
Regulators are also expected this
week to authorize antiviral pills from Pfizer and Merck,
the first two products in a new class of Covid treatments, according to two
senior administration officials.
Both pills can stave off severe
illness in the high-risk patients that until now might have received antibody
treatments. Pfizer’s treatment, known as Paxlovid, is especially promising, as
it has been found to be highly effective — and likely to work against Omicron.
Supplies of these antivirals will be
limited at first, but even modest amounts may help ease the strain on doctors
who had been relying until now on monoclonal antibodies to treat Covid
patients.
Still, Dr. Bob Wachter, chairman of
the Department of Medicine at University of California, San Francisco, warned
that limited availability of antibody treatments might come as a shock to
patients who assumed they would be a reliable, potent treatment.
“If you have chosen to be less safe
than you might have been, either because of your choice of vaccines or your
choice of masking, it’s a riskier proposition than it would have been a couple
weeks ago,” Dr. Wachter said.
Late last year, Regeneron and Eli
Lilly received authorizations for monoclonal antibody treatments made by
analyzing the blood of people who had recovered from the disease early in the
pandemic.
Each patient produced a vast number
of different antibodies. The companies zeroed in on one or two that proved
especially potent at stopping earlier versions of the coronavirus.
Clinical trials showed that these
antibodies were effective at preventing hospitalization if given to people
early in the course of their illness. President Trump received monoclonal antibodies
made by Regeneron during his bout with Covid.
At first, doctors struggled to
obtain scarce doses. The drugs were typically administered as infusions at
hospitals or clinics, with sessions sometimes lasting several hours. Despite
the inconvenience, monoclonal antibodies went into widespread use for treating
Covid.
Some hospitals made them more
accessible by setting up drive-through monoclonal antibody clinics. Doctors
even began giving the drugs to people merely exposed to the coronavirus, as a
way of preventing them from getting sick.
Nearly 68,000 doses of monoclonal
antibodies were given nationwide last
week, according to the Department of Health and Human Services. Most
of the patients got Regeneron’s treatment, followed by Eli Lilly’s.
When the coronavirus variants began
emerging a year ago, researchers found that some had gained resistance to
monoclonal antibodies. A mutation to their surface proteins prevented the
antibodies from sticking to the viruses, a necessary step in neutralizing them.
For several months, the government paused
distribution of Eli Lilly’s antibody treatment nationwide because it proved
ineffective against variants such as Gamma, which emerged in Brazil and
spread to many countries last spring.
Fortunately, doctors could still
give out Regeneron’s treatment, which remained effective against the variants
and was in abundant supply. Other variants largely vanished from the United
States as Delta surged to dominance this summer.
Delta proved susceptible to all of
the authorized antibody treatments. The Biden administration gave the green
light to Eli Lilly’s treatment once more and ordered hundred of thousands of
doses.
But Omicron has changed everything.
When the new variant was identified
last month in southern Africa, researchers began laboratory studies testing
monoclonal antibodies to see how well they worked against it. Scientists found
that both Regeneron and Lilly’s antibodies did a poor job of blocking the
variant virus from invading cells. Sotrovimab, by contrast, remained potent.
George Scangos, the chief executive
of Vir, attributed the resilience of sotrovimab to the strategy researchers
used to find it. Rather than look in the blood of Covid survivors, researchers
examined the blood of people who had survived the 2003 SARS epidemic, caused by
a related coronavirus.
They identified an antibody from a
SARS survivor that also protected against the coronavirus that caused Covid.
That double action suggested that the sotrovimab antibody attached itself to a
part of the virus that has changed very little over the course of its
evolution. And it would be unlikely to change in new variants, the researchers
reasoned.
“I think we got here not by good
luck, but by a thoughtful process,” Dr. Scangos said.
At New York Community Hospital in
Brooklyn, clinicians have been administering the Regeneron and Eli Lilly
treatments to about 100 Covid patients daily. The hospital ran out of its
supply of the GSK-Vir treatment several weeks ago.
“If I had a choice, I would give
GSK,” said Dr. Ralph Madeb, the hospital’s co-chief medical officer.
The federal government ordered about
450,000 doses of sotrovimab, at a cost of about $2,100 a person. Shipments
began in the fall. But as Omicron emerged, officials halted shipments of
GSK-Vir’s still effective sotrovimab to the states, in an effort to preserve
the supply as scientists determined how much of a threat the new variant would
be.
When it became clear that Omicron
was gaining a foothold, the government allocated 55,000 sotrovimab doses to
states, with shipments arriving as soon as this week. GSK is expected in
January to deliver 300,000 more doses to the United States.
“What matters most is the supply we
can have in January and February and March, and we’re doing everything we can
to increase that,” Dr. Scangos said.
Kathleen Quinn, a spokeswoman for
GSK, said that the companies are “actively working to expand our capacity,”
adding another production facility and accelerating production plans.
The expansion plans may not come
soon enough for places like the upper Midwest, which is already short of
monoclonal antibodies in the midst of a Covid surge.
Dr. Bruce Muma, president of the
Henry Ford Health System in Michigan, said health system and state officials
are bracing for a cutback on the Regeneron and Eli Lilly monoclonal antibodies,
while anticipating only a meager supply of sotrovimab.
Dr. Muma said demand for the
treatment already outstrips supply. He expects frontline staff to encounter
angry patients.
“They are going to be dealing with a
fearful population of patients who are not able to get what they feel they
should get,” he said.
“We can’t even afford the slightest
blip of a surge, and with Omicron that looks like what’s coming,” Dr. Muma
said.
Dr. Griffin, who sees patients in
New York City, said he expects difficult conversations now that major health
systems have halted their use until the more effective treatment arrives.
Vaccinated patients should still do
well, he said. But those most likely to be upset will be patients who “didn’t
want to get vaccinated but thought, ‘I can trust the monoclonals. If I need
them, they’ll be there for me.’”
The sudden appearance of Omicron has
pushed the Food and Drug Administration to quickly figure out how to regulate
monoclonal antibodies in this new chapter of the pandemic.
The agency “is working with sponsors
of all currently authorized therapeutics to assess the activity against any
global SARS-CoV-2 variant(s) of interest and is committed to communicating with
the public as we learn more,” according to agency spokeswoman Chanapa
Tantibanchachai.
Dr. Lindsay Petty, an infectious
disease specialist at the University of Michigan School of Medicine, said that
she and her colleagues were agonizing over when and if to switch from the
abundant monoclonal antibodies to the scarcer sotrovimab.
“Once we decide to change, we
anticipate we will be running out of drug supply each week,” she said.
Both Regeneron and Eli Lilly say
they are developing monoclonal antibodies for Omicron, but it will be months
before they are ready for use."
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