Refile: INSIGHT-U.S. companies, labs rush to produce blood test for coronavirus immunity

Sugentech

25/03/2020 10:00

(Refiling to fix Bioamerica Inc RIC)
    By Chad Terhune, Allison Martell and Julie Steenhuysen
    March 25 (Reuters) - As the United States works overtime to
screen thousands for the novel coronavirus, a new blood test
offers the chance to find out who may have immunity - a
potential game changer in the battle to contain infections and
get the economy back on track.
    Several academic laboratories and medical companies are
rushing to produce these blood tests, which can quickly identify
disease-fighting antibodies in people who already have been
infected but may have had mild symptoms or none at all. This is
different from the current, sometimes hard-to-come-by diagnostic
tests that draw on a nasal swab to confirm active infection.
    “Ultimately, this (antibody test) might help us figure out
who can get the country back to normal,” Florian Krammer, a
professor in vaccinology at Mount Sinai’s Icahn School of
Medicine, told Reuters. “People who are immune could be the
first people to go back to normal life and start everything up
again.”
    Krammer and his fellow researchers have developed one of the
first antibody tests in the United States for COVID-19, the
disease caused by the new coronavirus. Krammer said his lab is
busy distributing key ingredients for the tests to other
organizations and sharing the testing procedure. He is
transferring the work to Mount Sinai’s clinical lab this week so
it can begin testing patient samples.
    Antibody tests won’t face the same bureaucratic hurdles
diagnostic testing initially did. The U.S. Food and Drug
Administration relaxed its rules last month, and body-fluid
tests can proceed to market without full agency review and
approval.
    Several private companies have begun selling blood tests for
COVID-19 antibodies outside the United States, including
California-based Biomerica Inc  BMRA.O  and South Korean test
maker Sugentech Inc  253840.KQ . Biomerica said its test sells
for less than $10 and the company already has orders from Europe
and the Middle East. Chembio Diagnostics Inc  CMI.O  of New York
said it received a $4 million order from Brazil for its COVID-19
antibody test, and it plans a study of the test at several sites
in the United States.
    Such tests are relatively inexpensive and simple, usually
using blood from a finger prick. Some can produce results in 10
to 15 minutes. That could make ramping up screening much easier
than for diagnostic tests.
    Many questions remain, including how long immunity lasts to
this new virus, how accurate the tests are and how testing would
roll out, according to researchers and infectious disease
experts. For now, the number of people who have been able to
fight off the virus is unknown.
    If testing goes forward on a wider scale, some public health
experts and clinicians say healthcare workers and first
responders should take priority.
    Detecting immunity among doctors, nurses and other
healthcare workers could spare them from quarantine and enable
them to keep treating the growing surge of coronavirus patients,
they say. It could also bolster the ranks of first responders,
police officers and other essential workers who have already
been infected and have at least some period of protection from
the virus, the experts say.
     “If I ever get the virus and then get over it, I'll want to
get back to the front lines ASAP,” said Dr. Adams Dudley, a
pulmonologist and professor at the University of Minnesota
School of Medicine. “I would have a period in which I am immune,
effectively making me a ‘corona blocker’ who couldn’t pass the
disease on.”
    
    'VERY ATTRACTIVE'
    Other workers sidelined by lockdowns also could potentially
return to their jobs, providing a much-needed boost to the
foundering U.S. economy. The number of Americans filing for
unemployment benefits has soared, and business activity slumped
to a record low this month as the pandemic battered the
manufacturing and service sectors.
    Dr. William Schaffner, a professor of infectious diseases at
the Vanderbilt University School of Medicine, said companies,
schools, colleges and professional sports teams could all flock
to these tests. He also said a broad sample of testing could
give a governor or mayor enough confidence to lift certain
restrictions on businesses and schools if there is a strong
level of immunity.
    “These tests would be very attractive if they’re cost
effective, readily available and easy to do,” he said.
    Tony Mazzulli, chief microbiologist with Toronto's Sinai
Health system, sounded a note of caution. It is uncertain
whether antibodies would be sufficient protection if a person
were to be re-exposed to the virus in very large amounts. That
could happen in an emergency room or intensive-care unit, for
instance.
    The timing of a return to work and normal life also matters,
he said. Some people who have antibodies to the virus could
still be contagious, even if their symptoms have eased. Patients
begin to make antibodies while they are still sick, Mazzulli
said, and they continue to shed the virus for a few days after
they have recovered.
    It would be “a bit premature” to use the tests to make
staffing decisions now, Mazzulli said. “The hope is …
(antibodies) do confer protection and they can go to work, ride
the subways, whatever they do. But there's no guarantee.”
    Meantime, at the Mayo Clinic  MAYO.UL  in Rochester,
Minnesota, researchers are preparing to start a clinical trial
in which patients who test positive for COVID-19 would have
their blood collected at the time of diagnosis, and again 15 to
20 days after that in the patient’s home.
    The trial is designed to show when people who have COVID-19
infections “seroconvert” - when antibodies produced by the body
begin to show up in blood tests. That information will be useful
in determining the best time to conduct the tests. 
    “You don't want to do it too soon because of the risk of
false negatives,” said Elitza Theel, director of Mayo’s
Infectious Diseases Serology Laboratory.
    Mayo also is evaluating the performance of antibody tests
from several companies, including two from China.
    The U.S. Centers for Disease Control and Prevention said it
is working on its own version of  antibody tests, but it has not
given a timetable. The agency has said extensive research is
underway. One challenge for the CDC and other labs is to get
enough blood samples from people who have already been infected
to verify the antibody results.
    The agency faced heavy criticism for sending a faulty
diagnostic test to state and local labs early in the coronavirus
epidemic and then taking weeks to fix it. The federal government
is still trying to expand diagnostic testing capacity. 
    
    MONTHS OF IMMUNITY
    The potential for antibody testing arises as U.S. President
Donald Trump is considering scaling back “social distancing” and
stay-at-home advisories in the weeks ahead. His political allies
argue that the toll on the U.S. economy is too severe. About
half of Americans have been ordered to shelter in place as many
schools and businesses remain shuttered indefinitely.
    On Tuesday, Trump said: “I would love to have the country
opened up and just raring to go by Easter.”
    Reopening offices and businesses without fear of triggering
more infections, however, has been complicated by the lack of 
testing to diagnose COVID-19 cases across much of the country. 
    On Monday, Dr. Deborah Birx, a member of the White House
coronavirus task force, said simple, finger-prick antibody tests
could play an important role, and she suggested the federal
government is not waiting on the CDC’s version.
    “Some are developed now. We are looking at the ones in
Singapore,” Birx said Monday at a White House press briefing.
“We are very quality-oriented. We don’t want false positives.”
    False positives are erroneous results that, in this case,
could lead to a conclusion that someone has immunity when he or
she does not.
    Researchers at the Duke-National University of Singapore
Medical School said they quickly developed one antibody test
that had about 90% accuracy and later introduced a more
sophisticated version that was more reliable, according to a
report in the Straits Times of Singapore.
    Infectious disease experts say immunity against COVID-19 may
last for several months and perhaps a year or more based on
their studies of other coronaviruses, including Severe Acute
Respiratory Syndrome (SARS), which emerged in 2003. But they
caution that there is no way to know precisely how long immunity
would last with COVID-19, and it may vary person to person.
    “You are likely to have immunity for several months,” said
Dr. Stanley Perlman, a professor of microbiology and immunology
at the University of Iowa. “We just don’t know. This is an
incredibly important question.”
    Perlman said many of the new antibody tests coming on the
market now may be highly effective, but researchers want to see 
data to back that up.
    “You want them to be sensitive enough to detect everyone who
has had the infection,” Perlman said, “but not so nonspecific
that you are picking up other coronaviruses.” 

 (Chad Terhune reported from Los Angeles, Julie Steenhuysen from
Chicago and Allison Martell from Toronto; Editing by Julie
Marquis)
 ((chad.terhune@thomsonreuters.com))