MHRA Approves Oxford/AstraZeneca COVID-19 Vaccine

Tim Locke

December 30, 2020

Editor's note, 30 December 2020: This article was updated with the latest information from the MHRA.

The UK's Medicines & Healthcare products Regulatory Agency (MHRA) has approved the Oxford/AstraZeneca COVID-19 vaccine. 

Prime Minister Boris Johnson said it was "truly fantastic news - and a triumph for British science".

The rollout begins on 4 January for over-18s, with two standard doses, 4 to 12 weeks apart.

The first batch was released last night. England's Health Secretary Matt Hanock told the Commons: "We already have 530,000 doses available to the UK from Monday with millions due from AstraZeneca by the beginning of February."

Last month the UK was first to approve the Pfizer/BioNTech vaccine and rollout of that began in the NHS earlier this month. 

'Landmark Moment'

In a news release, Professor Andrew Pollard, director of the Oxford Vaccine Group and chief investigator of the Oxford Vaccine Trial, said: "The regulator’s assessment that this is a safe and effective vaccine is a landmark moment, and an endorsement of the huge effort from a devoted international team of researchers and our dedicated trial participants. Though this is just the beginning, we will start to get ahead of the pandemic, protect health and economies when the vulnerable are vaccinated everywhere, as many as possible as soon as possible."

Pascal Soriot, AstraZeneca chief executive officer, added: "Today is an important day for millions of people in the UK who will get access to this new vaccine. It has been shown to be effective, well-tolerated, simple to administer and is supplied by AstraZeneca at no profit. We would like to thank our many colleagues at AstraZeneca, Oxford University, the UK Government and the tens of thousands of clinical trial participants."

First Dose Priority

The Joint Committee on Vaccination and Immunisation (JCVI) also announced prioritisation of the first dose of both vaccines: "Having studied evidence on both the Pfizer/BioNTech and Oxford University/AstraZeneca vaccines, 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.

"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."

'No Corners Cut'

MHRA Chief Executive Dr June Raine told a Downing Street news briefing: "Our teams of scientists and clinicians have very carefully and methodically and rigorously reviewed all the data on safety, on effectiveness, and on quality, as soon as they have become available, and have done so round the clock, looking at all the tests and trials, even over holiday periods, no corners whatsoever, have been cut."

Professor Sir Munir Pirmohamed, chair of the Commission on Human Medicines Expert Working Group, said the initial half dose, full dose regimen results "were not borne out by the full analysis".

On pregnancy and breastfeeding, he said: "There is limited data on the use of this vaccine in pregnant or breastfeeding women. Women should discuss the benefits and risks of having the vaccine, with a health care professional based on their own individual circumstances and reach a decision together."

On allergic reactions: "We've come to the recommendation people with a known history of reacting to any specific ingredients of vaccine should not have it. But people with allergies to other medicines or food can have the vaccine."

On a possible reduction in virus transmission after vaccination, "we felt that the data was not mature enough to make any recommendations with regard to transmission," he said.

Professor Wei Shen Lim, JCVI COVID-19 chair, said there's been no head-to-head analysis of the two approved jabs, "so both vaccines may be used with no preference for one vaccine over the other".

However, logistics may mean one vaccine is offered in preference over another.

Protection is afforded for at least 3 months, and he said: "Data shared with us, and I'm not sure is entirely in the public domain, calculated the vaccine efficacy between day 22 of dose one to the time of dose two being given, and the figure is around 70%."

Mixing doses of the two different vaccines is not recommended but trials are planned to assess this approach.

On prioritising the first dose, he said: "We can expect that the amount of vaccine available for use in the UK will very substantially increase very, very soon. This increase in the vaccine supply will in turn allow a much higher rate of vaccine deployment across the UK to all parts of the country. And this is good news for all of us at a very critical time in this pandemic."

Prof Wei Shen Lim was asked if greater priority would now be given to NHS frontline workers: "Hopefully all NHS frontline workers will very soon be able to be offered a vaccine wherever they are," he said.

Other NHS workers and key workers would be in Phase 2 of the vaccination programme.

And he stressed: "The advice remains that everybody, including those who are vaccinated, should adhere to the latest government guidelines on social distancing measures and other protective measures."

Dr Raine concluded: "With this approval of the second vaccine we are another step closer in helping to defeat this virus."

Approval Process

The MHRA was asked to begin assessment of the Oxford vaccine on November 27.

On December 9, Dr Raine told MPs on the Commons Health and Science Committee that "data packages for the AstraZeneca/Oxford vaccine have been arriving" and that work was "proceeding intensively, and with great scientific rigour".

The final data were delivered to the regulator on December 23. At the time, Matt Hancock told a Downing Street briefing: "I have every confidence that the regulator will look at it with great capability. I want to put no pressure on them in terms of the decision or the timing of the decision."

Vaccine Results

Overall, the Oxford vaccine, ChAdOx1 nCoV-19, also known as AZD1222, demonstrated 70.4% protection against SARS-CoV-2, according to interim results released December 8 in The Lancet.

For participants who received two standard doses, vaccine efficacy was 62.1%.

In participants who received a low dose followed by a standard dose, efficacy was 90.0%.

Prof Pollard told a news briefing on 8 December the half dose, full dose approach that gave the best results wasn't planned. He dismissed concerns about the age of participants in that group saying the result "doesn't appear to be an age phenomenon".

Last weekend, AstraZeneca's Pascal Soriot told the Sunday Times: "We think we have figured out the winning formula and how to get efficacy that, after two doses, is up there with everybody else.

"I can't tell you more because we will publish at some point."

Vaccine Details

Oxford's vaccine is a chimpanzee adenovirus-vectored vaccine.

The UK has ordered 100 million doses.

Unlike the Pfizer/BioNTech vaccine that requires -70C storage, the Oxford vaccine will be easier to deliver as it can be stored at between 2C and 8C.

Pfizer/BioNTech Update

Dr Raine also gave an update on the latest recommendations on the Pfizer/BioNTech vaccine during pregnancy: "We have reviewed further data that has become available. The Commission on Human medicines has advised that the vaccine can be considered for use in pregnancy when the potential benefits outweigh the risks following an individual discussion with every woman."

On allergic reactions: "Anyone with allergy to food or other medicine or vaccine can have the Pfizer/BioNTech vaccine. Of course, anyone with a history of allergic reaction to this vaccine, or its ingredients should not."

Other Vaccines

Other COVID-19 vaccine trials are underway in the UK, including:

  • Imperial vaccine trial: A phase 2 trial of LNP-nCoVsaRNA – a self-amplifying RNA vaccine developed by Imperial College (414 participants)

  • Novavax COVID vaccine study: A phase 3 trial of NVX-CoV2373 – a recombinant spike protein nanoparticle vaccine developed by US biotech firm, Novavax (11,955 participants)

  • Janssen phase 3 vaccine study: A study that opened mid-November (aims to recruit 30,000 participants worldwide)


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