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(Adds manufacturing plans and progress)
By Julie Steenhuysen
CHICAGO, Jan 28 (Reuters) - Novavax Inc said on
Thursday its coronavirus vaccine was 89.3% effective in
preventing COVID-19 in a trial conducted in the United Kingdom,
and was nearly as effective in protecting against the more
highly contagious variant first discovered in the UK, according
to a preliminary analysis.
A mid-stage trial of the vaccine in South Africa, where a
troubling new variant of the virus is common, showed 60%
effectiveness among people who did not have HIV.
Novavax shares surged 34% in after hours trading following
release of the trial results on the same day the United States
reported its first cases of the South African
variant.
Novavax is already stockpiling vaccine at six operating
manufacturing locations, and said it expects a total of eight
plants in seven countries to produce at the rate of 2 billion
doses per year, including from the Serum Institute of India.
The company on a conference call noted that this was interim
data and executives said they expect it will be two to three
months before they are ready to apply for authorization with
regulators.
The UK trial, which enrolled 15,000 people aged 18 to 84, is
expected to be used to apply for use in Britain, the European
Union and other countries.
Approval of the Novavax vaccine would be most welcome in
Europe as it struggles with meager vaccine supply after
Pfizer/BioNTech and AstraZeneca Plc delivered fewer
doses than hoped.
Executives on the call said the company was discussing with
the U.S. Food and Drug Administration whether the UK and South
Africa data was enough to apply for U.S. emergency use
authorization.
The UK study took place as the more highly transmissible UK
variant was circulating. The preliminary analysis suggests the
vaccine was 85.6% effective against this mutation, the U.S.
company announced in its news release. It did not provide
detailed data.
In the UK trial, the effectiveness of the vaccine was close
to that of the two authorized vaccines from Pfizer Inc
with BioNTech SE and Moderna Inc, whose
two-dose regimens were both around 95% effective at preventing
COVID-19 in clinical trials.
'WE'VE GOTTEN SPOILED'
John Moore, a professor of microbiology and immunology at
Weill Cornell Medical College in New York, said the Novavax UK
data are essentially the same as results from Pfizer and
Moderna.
"It's not statistically different. The vaccine basically
works well in the predominant strain circulating in the UK,
which means it's likely to be equally effective in the United
States," he said.
Dr. Amesh Adalja, an infectious disease expert at the Johns
Hopkins Center for Health Security, said the results were in
line with hopes, and that he was concerned people would focus
too much on the weaker effectiveness shown in South Africa.
"We've gotten spoiled because we've seen the Moderna and
Pfizer numbers. I know people are going to be alarmed, but 60%
efficacy against the new variant is acceptable," he said, noting
that the FDA initially said it would approve a vaccine that was
at least 50% effective.
The South African variant has been shown to evade antibody
protection in lab studies by Moderna and Pfizer/BioNTech.
Novavax said it started making new versions of its vaccine
to protect against emerging virus variants in early January and
expects to select ideal candidates for a booster in the coming
days. The company said it plans to initiate clinical testing of
these new vaccines in the second quarter of this year.
A 30,000-person trial in the United States and Mexico that
began in December also is underway. The company has received
$1.6 billion from the U.S. government in funding for the vaccine
trial and for 100 million doses.
It also has received at least $388 million in backing from
the Coalition for Epidemic Preparedness Innovation (CEPI), a
Norway-based group backed by 14 governments, the Bill and
Melinda Gates Foundation, and Britain’s Wellcome Trust.
Authorized vaccines so far have been based on newer
technology platforms, such as the messenger RNA technology used
by Moderna and Pfizer/BioNTech, or inactivated cold virus
platforms used by Oxford University/AstraZeneca and CanSino
Biologics.
Novavax’s is a more conventional protein-based vaccine, an
approach similar to that used by Sanofi to make its
Flublok seasonal flu vaccine. The Novavax vaccine works with the
company's proprietary Matrix-M adjuvant used to boost its
efficacy.
(Reporting by Caroline Humer, Julie Steenhuysen and Vishwadha
Chander; Editing by Peter Henderson and Bill Berkrot)
