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(Adds comment from Novavax executive)
By Dania Nadeem and Carl O'Donnell
March 11 (Reuters) - Novavax Inc's COVID-19 vaccine
was 96% effective in preventing cases caused by the original
version of the coronavirus in a late-stage trial conducted in
the United Kingdom, the company said on Thursday, moving it a
step closer to regulatory approval.
There were no cases of severe illness or deaths among those
who got the vaccine, the company said, in a sign that it could
stop the worse effects of new variants that have cropped up.
The vaccine was 86% effective in protecting against the more
contagious virus variant first discovered and now prevalent in
the United Kingdom, for a combined 90% effectiveness rate
overall based on data from infections of both versions of the
coronavirus.
Novavax shares jumped 22% in after-hours trading to $229.
They were trading below $10 on Jan. 21, 2020, when the company
announced it was developing a coronavirus vaccine.
In a smaller trial conducted in South Africa - where
volunteers were primarily exposed to another newer, more
contagious variant widely circulating there and spreading around
the world - the Novavax vaccine was 55% effective, based on
people without HIV, but still fully prevented severe illness.
Novavax Chief Medical Officer Filip Dubovsky said the
performance in South Africa suggests there may still be a case
for using it in areas where the South African variant is
dominant.
Novavax is also developing new formulations of its vaccine
to protect against emerging variants and plans to initiate
clinical testing of these shots in the second quarter of this
year.
Results from the final analysis of the UK trial were largely
in line with interim data released in January.
The company expects to use the data to submit for regulatory
authorization in various countries. It is not clear when it will
seek U.S. authorization or if regulators will require it to
complete an ongoing trial in the United States.
Novavax expects data from a 30,000-person trial in the
United States and Mexico by early April.
Dubovsky said that Novavax is still planning to file for
authorization from UK regulators early in the second quarter of
2021.
The UK trial, which enrolled more than 15,000 people aged 18
to 84, assessed efficacy of the vaccine during a period with
high transmission of the UK virus variant now circulating
widely.
The shot's effectiveness in the South Africa trial declined
to around 49% when the analysis included data from HIV-positive
participants.
The vaccine could be cleared for use in the United States as
soon as May if U.S. regulators decide the UK data is enough to
make a decision. It could take a couple months longer if they
insist on first seeing data from the U.S. trial, its chief
executive told Reuters earlier this month.
"Ultimately, they have to decide whether the data we can
bring to the table is adequate or whether they would prefer to
wait on data from our U.S. study," Dubovsky said on Thursday.
Novavax’s vaccine production plants should all be fully
functional by April, executives said on a March investor call.
The drugmaker expects to have tens of millions of doses
stockpiled and ready to ship in the United States when it
receives authorization, CEO Stanley Erck told Reuters.
Novavax plans to produce its two-shot vaccine at eight
manufacturing locations, including the Serum Institute of India.
If authorized, it would follow three COVID-19 vaccines
previously approved for use in Britain from Pfizer and
partner BioNTech, Moderna Inc and the
AstraZeneca shot developed with Oxford University.
The Maryland-based company has received $1.6 billion from
the U.S. government in funding for the vaccine trial and to
secure 100 million doses.
(Reporting by Dania Nadeem in Bengaluru and Carl O'Donnell in
New York; Editing by Bill Berkrot and Lisa Shumaker)
