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* FACTBOX-AstraZeneca's deals to produce and supply its
COVID-19
vaccine
* FACTBOX-How AstraZeneca-Oxford developed Britain's
home-grown
COVID-19 vaccine
March 25 (Reuters) - AstraZeneca published updated
results from its major U.S. COVID-19 vaccine trial, after health
officials there publicly criticized it for using "outdated
information" to show how well the immunization worked.
On Thursday, AstraZeneca said its COVID-19 vaccine was 76%
effective in the new analysis of the U.S. trial, a tad lower
than the level reported earlier.
Here's a look at the progress of the vaccine development to
date since its inception.
JANUARY 2020:
A team involving Oxford Vaccine Group and Jenner Institute
starts work on developing a vaccine to prevent COVID-19.
MARCH 2020:
Researchers at the Oxford University begin screening healthy
volunteers, aged 18-55, for recruitment in the ChAdOx1 nCoV-19
vaccine trial in the Thames Valley Region.
APRIL 2020:
Human trials begin
AstraZeneca and Oxford join forces for development and
potential large scale distribution of the vaccine candidate.
MAY 2020:
AstraZeneca and Oxford start recruiting volunteers for a
much larger human trial in the UK.
JULY 2020:
Initial safety data released showed vaccine was safe and
produced an immune response.
AUGUST 2020:
Vaccine candidate begins late-stage study in the United
States.
SEPTEMBER 2020:
AstraZeneca suspends global trials due to an unexplained
illness in a study participant.
AstraZeneca resumes UK trials.
Oxford/AstraZeneca begin submitting data to the UK regulator
under a rolling review process.
OCTOBER 2020:
EU launches real-time review of the vaccine.
United States restarts trial, the last one to do so after
other regions began resumption much earlier.
NOVEMBER 2020:
AstraZeneca confirms that the UK regulator has started an
accelerated review of vaccine.
Interim late-stage data from UK, South Africa trials
released:
The vaccine on average prevented 70% of COVID-19 cases in
late-stage trials in Britain and Brazil.
The success rate rose to 90% in a group of trial
participants who accidentally received a half dose followed by a
full dose.
The efficacy was 62% if the full dose was given twice, as it
was for most study participants.
DECEMBER 2020:
Russia's sovereign wealth fund says AstraZeneca will begin
clinical trials to test a combination of its experimental
COVID-19 vaccine with Russia's Sputnik V shot in hopes to boost
efficacy.
Britain approves shot in first for COVID-19 vaccines in the
West. Regulators said that the higher efficacy seen in the
half-dose/full-dose cohort was likely a result of a longer gap
between doses, rather than the amount of vaccine given.
JANUARY 2021:
India approves Serum's vaccine days later in early January.
Europe gives vaccine green light in late January.
FEBRUARY 2021:
The World Health Organisation gives the vaccine a go-ahead.
MARCH 2021:
AstraZeneca cut its first-quarter supply forecast to the EU
due to export constraints.
Austria halts use of one batch of vaccine following reports
of cases of blood clots in Nordic countries.
More than a dozen European countries, including Germany and
France, followed suit and halted use of the vaccine.
European regulators and WHO back vaccine's safety in
mid-March, but poll shows European confidence has taken a hit.
In late March, interim data from late-stage trials in U.S.,
Peru, Chile shows vaccine is 79% effective.
Just after, the U.S. National Institute of Allergy and
Infectious Diseases said the drugmaker may have included
outdated information from the trial, providing an incomplete
view of the efficacy data.
AstraZeneca issues clarification on interim study, adding
that data was based on data through Feb. 17
Canada backs vaccine, but updates label to include
information on blood clots.
(Reporting by Pushkala Aripaka, Yadarisa Shabong and Vishwadha
Chander in Bengaluru; Editing by Hugh Lawson and Emelia
Sithole-Matarise)
