UK regulators approve Oxford/AstraZeneca coronavirus vaccine

(CNN) -- UK regulators have approved the use of the Oxford University/AstraZeneca coronavirus vaccine, which is cheaper and easier to distribute than some alternatives and could in time offer a route out of the pandemic for large parts of the world.

The UK government said it would follow a new immunization strategy for the vaccine, which will prioritize giving the first in a series of two vaccine doses to as many people as possible, before administering a second dose up to 12 weeks later.

This will apply to both the newly approved Oxford/AstraZeneca vaccine and the Pfizer/BioNTech vaccine which is already being rolled out.

"This is important because it means that we can get the first dose into more people more quickly and they can get the protection the first dose gives you," UK Health Secretary Matt Hancock told Sky News on Wednesday.

"The scientists and the regulators have looked at the data and found that you get what they call 'very effective protection' from the first dose. The second dose is still important -- especially for the long-term protection -- but it does mean that we will be able to vaccinate more people more quickly than we previously could."

The UK is the first country to approve the Oxford University/AstraZeneca vaccine. The news represents a glimmer of hope for the country at a time when its health services are struggling to cope with soaring infection rates linked to a new, more contagious variant of the virus.

The approval comes weeks after the country became the first in the world to start inoculating its citizens with the rival Pfizer/BioNTech coronavirus vaccine.

UK government scientific adviser Professor Calum Semple welcomed what he called a new, "sophisticated approach," telling Sky News that a "one-dose approach to start with will protect a great many people."

According to Semple, evidence from vaccine trials has shown that a single dose has not only prevented people from getting the severe disease but also has prompted a "very good immune response" in frail and elderly people.

In a statement early Wednesday, the UK government said the Medicines and Healthcare Products Regulatory Agency (MHRA) had authorized Oxford University/AstraZeneca's Covid-19 vaccine following "rigorous clinical trials and a thorough analysis of the data by experts at the MHRA."

AstraZeneca said the first doses were being released Wednesday, so that UK vaccinations could begin early in the New Year.

The Oxford University/AstraZeneca vaccine has the potential swiftly to protect millions more people around the world as and when other nations' regulators grant approval.

AstraZeneca has promised to supply hundreds of millions of doses to low and middle-income countries, and to deliver the vaccine on a not-for-profit basis to those nations in perpetuity.

The vaccine is significantly cheaper than others which have been approved and, crucially, it would be far easier to transport and distribute in developing countries than its rivals since it does not need to be stored at freezing temperatures.

"I think it's the only vaccine that can be used in those settings at the current time," Azra Ghani, chair in infectious disease epidemiology at Imperial College London, told CNN. "Pfizer and Moderna require freezer storage, and that just isn't in place in many settings."

Minister: 'Fantastic news'

UK health services are coming under increasing pressure as Covid-19 cases soar in many regions.

The UK recorded a further 53,135 coronavirus cases on Tuesday, breaking its daily record since the pandemic began for a second day in a row.

Dr. Susan Hopkins, senior medical adviser for Public Health England, said in a statement: "We are continuing to see unprecedented levels of Covid-19 infection across the UK, which is of extreme concern particularly as our hospitals are at their most vulnerable."

Millions more people in England are expected to be placed under the country's toughest "Tier 4" restrictions on Wednesday amid attempts to limit the spread of a new variant that health officials say is more transmissible than other strains of the virus.

Speaking on Sky News, Hancock describing the approval of the Oxford/AstraZeneca vaccine as "fantastic news" and said the country's National Health Service was "standing ready to deploy, at the sort of pace that is needed to be able to help us to get out of this pandemic by the spring."

The UK government said the Oxford University/AstraZeneca vaccine met "strict standards of safety, quality and effectiveness" as it announced its approval.

"The NHS has a clear vaccine delivery plan and decades of experience in delivering large scale vaccination programs," the statement said. "It has already vaccinated hundreds of thousands of patients with the Pfizer/BioNTech vaccine and its rollout will continue. Now the NHS will begin putting their extensive preparations into action to roll out the Oxford University/AstraZeneca vaccine."

Dosing regimen

Previously, the team developing the vaccine said it had an "an average efficacy of 70%," with one dosing regimen showing an efficacy of 90%.

"Excitingly, we've found that one of our dosing regimens may be around 90% effective and if this dosing regime is used, more people could be vaccinated with planned vaccine supply," Andrew Pollard, chief investigator of the Oxford Vaccine Trial, said in November.

The Oxford/AstraZeneca vaccine can be kept at refrigerator temperatures of 2 to 8 degrees Celsius (36 to 46 degrees Fahrenheit) for at least six months.

Moderna's vaccine has to be stored at minus 20 degrees Celsius (minus 4 degrees Fahrenheit) -- or at refrigerator temperatures for up to 30 days -- and the Pfizer/BioNTech vaccine has to be stored at minus 75 degrees Celsius (minus 103 degrees Fahrenheit), and used within five days once refrigerated at higher temperatures.

"Cold chain" refrigeration is the standard storage used globally to deliver vaccines from central locations to local health clinics. AstraZeneca's vaccine is so far "the only one that can definitely be delivered to those systems," added Ghani.

The vaccines are based on different technology. AstraZeneca's offering -- like Johnson & Johnson's vaccine and Russia's Sputnik V -- uses an adenovirus to carry genetic fragments of coronavirus into the body.