Last checked at 
(Adds talks with US FDA, background on supply plans, vaccine
details)
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
potent variant of the virus is common, showed 60% effectiveness
among people who did not have HIV.
Novavax shares rose 26% in after hours trading following the
report, which comes on the day the United States reported its
first cases of the South African variant.
Novavax said the UK trial, which enrolled 15,000 people aged
18 to 84, is expected to be used to apply for regulatory review
in Britain, the European Union and other countries. Some 27% of
people in the trial are over age 65.
Executives on a conference 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.
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.
The study took place as the more highly transmissible UK
variant was circulating, and the preliminary analysis suggests
the vaccine was 85.6% effective against this mutation, the U.S.
company announced in a news release. It did not provide the
study 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 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 for the vaccines 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 that 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 U.S. Food and Drug Administration 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 and BioNTech.
“The 60% reduced risk against COVID-19 illness in vaccinated
individuals in South Africans underscores the value of this
vaccine to prevent illness from the highly worrisome variant
currently circulating in South Africa, and which is spreading
globally," Professor Shabir Maddi, lead investigator of the
Novavax vaccine trial in South Africa.
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.
Novavax is also running a 30,000-person trial in the United
States and Mexico that began in December after at least two
delays it said were due to manufacturing scaling issues that
prevented clearance by the FDA.
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), an
Oslo, Norway-based group backed by 14 governments, the Bill and
Melinda Gates Foundation, and Britain’s Wellcome Trust.
Novavax has said it could produce up to 2 billion doses
globally in 2021, once its manufacturing capacity is brought
online.
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 vaccine 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)
