The United Kingdom on Wednesday became the first country in the world to approve the coronavirus vaccine developed by the University of Oxford and drugmaker AstraZeneca.
The government said in its announcement that the green light “follows rigorous clinical trials and a thorough analysis of the data by experts” at the regulator, the Medicines and Healthcare products Regulatory Agency, “which has concluded that the vaccine has met its strict standards of safety, quality and effectiveness.”
U.K. Health Secretary Matt Hancock told the BBC “hundreds of thousands” of doses of the new vaccine would be available “from Monday.”
The U.K. also said in the announcement that it would change the way it would prioritize the administration of the vaccine, upon the recommendation of the Joint Committee on Vaccination and Immunisation (JCVI).
The JCVI “has advised the priority should be to give as many people in at-risk groups their first dose, rather than providing the required two doses in as short a time as possible,” the announcement said. “Everyone will still receive their second dose and this will be within 12 weeks of their first. The second dose completes the course and is important for longer term protection.”
Vaccination requires two doses. Rather than given 28 days apart, as done during the clinical trials, the committee advised “the priority should be to give as many people in at-risk groups their first dose, rather than providing the required two doses in as short a time as possible,” the announcement said.
The second dose will be administered within 12 weeks.
“Everyone will still receive their second dose,” the government said, adding that the second dose “completes the course and is important for longer term protection.”
Hancock told Times Radio that the approval of a second vaccine, after the BioNTech/Pfizer jab, means “I now have a very high degree of confidence that by the spring, enough of those who are vulnerable will be protected, to allow us to get out of this, this pandemic situation.”
The U.K. has ordered 100 million doses of the Oxford/AstraZeneca vaccine. Added to the 40 million doses of BioNTech/Pfizer’s jab, today’s news means the country has enough vaccines to immunize every eligible British citizen against coronavirus.
The Oxford/AstraZeneca vaccine can be stored between 2 degrees Celsius and 8 degrees — the same temperature as a fridge. This makes it easier to distribute than the BioNTech/Pfizer vaccine which needs to be stored at minus 70.
The news comes amid a winter surge in coronavirus cases in the U.K., which recorded more than 53,000 new cases on Tuesday and 414 new deaths. The pandemic has put hospitals under levels of pressure that now exceed its April peak.
“This is the fruition of decades of ground-breaking vaccinology and hard graft by the team at the Jenner [Institute] in Oxford,” said Danny Altmann, professor of immunology at Imperial College London.
He added in emailed comments that a “rapid, efficient vaccination program with good population coverage is our only way out.”
The MHRA reached its opinion after assessing clinical data that showed the vaccine was on average 70 percent effective at preventing disease.
In trials, the vaccine was 90 percent effective in more than 2,700 people who received a half dose followed by a full dose. It was 62 percent effective in more than 8,800 people who received two full doses.
Some observers had criticized AstraZeneca for the different dosing schedules across the trials. The lower dose was the result of an unintended manufacturing dilution process.
The vaccine is based on the adenovirus viral vector technology, which is also used by Johnson & Johnson, Russia’s Sputnik vaccine and some Chinese coronavirus vaccines.
A government spokesperson said the second dose would be the standard full dose and not a lower dose. It will be available to those aged 16 and over.
Scientists meanwhile welcomed the rapid approval of the vaccine, as well as the new first-dose prioritization plan.
This will “maximise the number of at-risk groups receiving the vaccine,” Lawrence Young, professor of molecular oncology at Warwick Medical School, said by email.
The U.K. used an EU loophole to allow the temporary supply of coronavirus vaccines during an emergency. The country will have free rein to fully authorize further coronavirus vaccines as of January 1, after the Brexit transition period ends.
The European Medicine Agency is also reviewing the data on the Oxford/AstraZeneca vaccine in a rolling review format. It recommended a full conditional marketing authorization for BioNTech/Pfizer’s vaccine on December 21.
EMA Deputy Executive Director Noël Wathion told Het Nieuwsblad newspaper in an interview published Tuesday that, for Oxford/AstraZeneca, the the agency had not yet received sufficient information “to warrant a conditional marketing license.”
This article has been updated.