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expert reaction to the Oxford AstraZeneca COVID-19 vaccine being approved for use in the UK by the MHRA

It has been announced this morning that the UK government has accepted the recommendation from the independent Medicines and Healthcare products Regulatory Agency (MHRA) to approve the Oxford-AstraZeneca COVID-19 vaccine for use.


Prof Sheila Bird, Formerly Programme Leader, MRC Biostatistics Unit, University of Cambridge, said:

“Bookings for a person’s first dose of the Pfizer vaccine are not accepted unless the person can guarantee to return for the second dose within a specified time-window during which booking for their 2nd dose is assigned.

“Those who are first to receive the Oxford/AstraZeneca vaccine should do so on the basis of agreement to return for their second dose within a specific fortnight during the period 4 to 12 weeks after their first dose.  Hence, I support the suggestion by Prof Sir Jeremy Farrar that major tranches of the first recipients of the Oxford/AstraZeneca be randomised to receive their second dose during weeks 4-6; 7-9; 10-12.  Initially, randomisation might be unequal, for example [30%; 40%; 30%] to favour the longer delays between doses – as occurred inadvertently in the randomised controlled trials.  Alternatively, the choice might be [40%; 30%; 30%] to learn more about the shorter interval, including in older citizens who may have most to gain from their second dose.

“UK has excellent major Clinical Trials Units who could assist in delivering a rigorous protocol which could include adaptive randomisation, whereby the randomisation-ratio is adjusted, say by age-group, on the basis of emergent information about SARS-CoV-2 diagnoses and hospitalisations of those randomised to different dosing-intervals.  Effective randomisation of the large numbers initially vaccinated will ensure efficient, unbiased learning.”


Dr Julian Tang, Honorary Associate Professor/Clinical Virologist, University of Leicester, said:

“So from Matt Hancock’s and the Oxford team’s various interviews/briefing it seems like there has been a shift away from the discussion around comparing the absolute vaccine efficacy figures – towards just focusing on reducing the severity of COVID-19 illness and keeping people out of hospital – even with just one dose of the Oxford AstraZeneca vaccine.

“Not surprisingly, only the two standard dose regimen has been approved by the MHRA – with a variable interval (4-12 weeks apart) between the first and second dose – for all ages 18 years and above, despite relatively limited data for the over 65 year groups.

“Not enough data was available to approve the low dose vaccination regimen.

“But practically, the Oxford vaccine will be cheaper and easier to transport and distribute to care homes and other vaccination sites – since it can be stored at normal fridge temperatures like the flu vaccine (2-8 C) – and this will help its distribution and use in developing countries.

“The idea to just vaccinate as many vulnerable individuals as possible with just one dose of either vaccine (Pfizer or AstraZeneca) to start with, is a good approach given the recent surges of COVID-19 cases since Christmas – and we may yet see further surges due to the Christmas Day amnesty that allowed multiple households to meet under one roof.

“There is no problem with receiving this vaccine after having had COVID-19 already.  This is the same for the seasonal flu vaccine.

“It is still yet to be seen if/how the Russian Sputnik V vaccine will be used to increase the overall efficacy of the Oxford-AstraZeneca vaccine – and whether there will be a trial to mix/match doses of different vaccines to increase overall vaccine efficacy.

“But above all, we need to continue with our current or even more intense restrictions on social contact and mixing to reduce the current surges in COVID-19 cases, to avoid overwhelming healthcare services, as well as making time for the vulnerable to receive their COVID-19 vaccines before they become infected.”


John Iredale, PVC Health and Life Sciences, University of Bristol, said:

“This is excellent and very welcome news at the end of a difficult year.  The approval of the Oxfod AZ vaccine by the independent MHRA opens up a further population wide approach to tackle Covid; both for the UK and, one anticipates, for the rest of the world including those countries whose infrastructures are better suited to storage and distribution at “fridge” temperatures.”


Dr Jeremy Farrar, Director of Wellcome, said:

“To start 2021 with the rollout of a second vaccine – and one which has many advantages for global supply – is a moment to be celebrated.  It does not mark the end of this crisis – in the UK and around the world there are still many, many difficult months ahead.

“The speed of development for this and other vaccine candidates is testament to an extraordinary global research effort and investment in basic science over many years.  This vaccine is particularly exciting as it can be easily administered in existing healthcare systems around the world, stored at fridge temperature and can use existing delivery mechanisms.

“This decision, independent from government or other external influence, begins to clear the path for this vaccine to be rolled out to a wider population.  As normal for any vaccine, there will be a need for close and continued monitoring for safety and efficacy as it is delivered.  We will also need to continue tracking and improving our understanding of how long the protection lasts and whether they can prevent transmission.  This would be best achieved by a randomised trial on the timing of the second dose.  We must ensure the maximum number of people are protected before and throughout the winter of 2021/2022.

“Now begins the enormous task of scaling up vaccination to as many people as possible.  It is much better to vaccinate as many people as possible with one dose, than half that number of people with two doses in the next few months.  It remains critical that groups most at risk, such as the elderly and frontline healthcare and essential workers, are prioritised to receive the first doses, but we must not delay getting the vaccine to everyone, in this country and around the world.  The dosing regimen announced today will allow a more rapid rollout.

“But there is no value in just vaccinating one country or one population, vaccines must be available to the whole world at the same time as promised by many politicians.  If we continue vaccinating only people in rich countries, while allowing the virus to continue to spread unchecked in other parts of the world, then new variants will emerge in these parts of the world against which our vaccines and treatments may no longer work.  And these new variants will inevitably spread around the world.  Then we are all be back to square one.

“We must keep asking ourselves ‘are we doing enough’ and responding fast to new and continued challenges, in order to save lives now and as we move into 2021.  Like everyone I wish life could get back to normal, but the UK is in a precarious position.  We must remain humble, cases are increasing and hospitals in UK are treating more patients today with COVID than at any time during this pandemic.  This after an already incredibly very difficult year.  We have to reduce transmission to prevent hospitalisations and deaths.

“Great credit and thanks go to Oxford, AstraZeneca, NIHR, CEPI, EU, Wellcome and many other organisations whose ongoing support has made this vaccine possible.  We must also pay tribute to healthcare workers and global research community everywhere, working tirelessly on behalf of all of us.  We owe them all our thanks and support and to be willing to take every precaution.”


Dr Jonathan Stoye, Group Leader, Retrovirus-Host Interactions Laboratory, The Francis Crick Institute, said:

“In light of the sharply increasing number of cases, the approval of the Oxford/AZ vaccine is tremendous news.  We all owe an enormous debt to those involved in the creation and testing of the vaccine as well as to the flexibility of the approval process.  However, the reported news does leave unanswered a number of important questions, particularly regarding the longer term.  These include:

“What is the real efficacy of the vaccine?  How well does it work in older people?

“Does it prevent virus transmission from person to person?

“What do we really know about dosing schedules?  If the original study design called for a 4-week interval between first and second doses, how much firm information do we have about varying this time?  Is there flexibility to extend this period beyond 12 weeks?

“Before Christmas about 50,000 people a day were immunised.  How much will introduction of this new vaccine improve the rate?

“The number of people identified in the first phase of the vaccine plan comprises nearly 40 million individuals.  Unless a vaccination rate of over 3 million a week can be achieved and assuming a maximum interval of 12 weeks before shots, this will inevitably mean that some people will be expecting their second shot before others have received their first.  Will this give rise to tensions?  Will the priority list be subdivided, say between groups 5 and 6?  How will decisions be made about the relative values of first and second shots?

“Can one identify correlates of protection – can we tell if someone is protected and can we tell how long immunity lasts?

“What fraction of the population will need to be vaccinated to suppress the disease as opposed to protecting from its consequences?  How long will this take?”


Dr Simon Clarke, Associate Professor in Cellular Microbiology at the University of Reading, said:

“The announcement of the Oxford-AstraZeneca is very welcome, giving us another weapon to fight with which to fight Covid-19.  The conditions for use allow the second dose of the vaccine up to 12 weeks after the first, with some protection being provided from 22 days.  It remains unclear exactly how much protection is offered, and the regulators are using un-published data to come to their judgement.

“When questioned, the regulators floated an efficacy of 70% between 22 days and 12 weeks, but it seems likely that this is a fleeting maximum rather than a consistent level of protection.  The vaccine’s efficacy after 2 doses is 62%, so it looks likely that the higher number would only be very short lived.

“At a time of increasing rates of infection, hospitalisation and death from Covid-19, greater clarity is urgently needed over any risks associated with extending the second dose window to 12 weeks.  It would be deeply unfortunate to increase the risk of vulnerable people so that low risk individuals can receive their first dose of the vaccine.  At worst, this could mean a vulnerable person dying or going to Intensive Care, in order to stop a less vulnerable person having to spend a week ill in bed.”


Dr Gail Carson, Deputy Chair of the Global Outbreak Alert and Response Network, said:

“Super news today from the UK authority that regulates and approves Medicines including vaccines for use in the UK.  Thank you to Oxford colleagues for developing a vaccine that can be of use globally.  Let’s not think solely nationally as the new variants show us we will be safe once we are all safe.  The International initiatives such as COVAX and the WHO will require ongoing support as we see other countries approve the roll out of this vaccine.  To ensure vaccine uptake we must put communities, people at the centre and engage with them, listen to any concerns they may have and address those concerns.

“Going forward we have to maintain the measures that have been asked of us as our health system is stressed caring for COVID-19 patients and we remain uncertain about the impact the vaccines have on transmission.  Plus, we must continue to respond to Long Covid with holistic care and research to inform prevention and care of people living with Long Covid.  The pandemic is not over but there is hope as we go into 2021!”


Dr Gillies O’Bryan-Tear, Chair, Policy and Communications, Faculty of Pharmaceutical Medicine, said:

“The Faculty of Pharmaceutical medicine welcomes the emergency authorisation of the AZ/Oxford vaccine.  We now have two vaccines available for use in the UK, the Pfizer/BioNTech vaccine, and now the Oxford/AZ vaccine, with many others still in development.  The Moderna vaccine is approved for use in the USA and may be approved soon in the UK also.

“As the recent days have shown, controlling the virus continues to be challenging and the need to vaccinate people as fast as possible is critical, therefore the availability of more vaccines is welcome to prevent people getting ill, needing to go into hospital or dying.

“The AZ/Oxford vaccine is an adenovirus vector vaccine and is the first one of this type to be approved for prevention of COVID-19 disease.  It is based on the technology used for other vaccines including one against Ebola.

“The vaccine is approved as the full dose/full dose regimen for people over 18 years of age, requiring two doses for the full effect.

“Separately, the Joint Committee on Vaccinations and Immunisations and the DHSA have issued guidelines that as many people as possible should receive a first dose of the vaccine, followed up to 12 weeks later by the second dose.  The reason for this is that a greater percentage of the population can thereby be protected, since significant, though not full immune protection is apparent after the first dose with both the Pfizer/BioNTech vaccine and the Oxford vaccine.  Crucially, no deaths were observed after the first doses of either of the vaccines.

“The vaccine can be stored at 2-8 degrees which is consistent with established vaccination delivery procedures.

“As with all vaccines that are approved by the MHRA, this vaccine has demonstrated rigorous safety and quality standards enabling widespread use.  Effectiveness and safety monitoring will be continued following use of the vaccine in practice; any person experiencing side effects after receiving the vaccine can report these to the MHRA using the Coronavirus Yellow Card App.”


Prof Saad Shakir, Director of the Drug Safety Research Unit (DSRU) near Southampton, said:

“Oxford/AstraZeneca vaccine has been approved by the MHRA in the UK New vaccination schedule – up to twelve weeks between the two doses of Covid-19 vaccines.  The MHRA has approved two full doses.  However, the Joint Committee on Vaccination and Immunisation (JCVI) in the UK recommended an entirely new strategy.  Everyone will be given a single dose to give some early immunity to the largest number of people.  The second dose will be given twelve weeks later, they say for long term immunity.  Published data from the main efficacy study of the Oxford/AZ vaccine in clinical trials was 62% and 90% with different strengths of the first dose.  The Chairman of the JCVI said that the single dose of AZ vaccine is 70% efficacious based on limited unpublished data.  More needs to be known because many points about these decisions remain unclear.  MHRA and JCVI promised to provide more information urgently.”


Prof Lawrence Young, Professor of Molecular Oncology, Warwick Medical School, said:

“MHRA chief executive Dr June Raine has provided detailed information on the thorough review of the Oxford AstraZeneca vaccine that has led to today’s approval.  The first batch of the vaccine was released for use last night.  Two standard doses have been approved with the second dose being administered 4-12 weeks after the first dose.  The vaccine provides some protection 22 days after the first dose.  Results of the half dose regimen was not borne out by the full analysis.  The safety profile is broadly similar to other vaccines.  People with a known history of allergies to vaccines need to seek advice from their GP.  The vaccine can be stored at 2-8 degrees centigrade for at least 6 months making the logistics of transportation and storage much easier.

“Having reviewed the safety data on the Pfizer/BioNTech vaccine, the MHRA have revised their guidance and use is permitted for pregnant women and those breastfeeding following a benefit/risk discussion.  The second dose of this vaccine can be administered at least 21 days after the first dose.  The Joint Committee on Vaccination and Immunisation have confirmed that both vaccines can both be used with no preference.  To increase vaccine coverage and rapidly roll out vaccination, delivery of the first dose should be prioritised but the second dose is still important as this may affect both the level and duration of protection.  As the second dose of both vaccines can be given up to 12 weeks later, this will increase the rate of vaccine deployment.  There is no data on whether these vaccines have any effect on transmission.  There is no reason to believe that the new variant virus will evade the effectiveness of these vaccines but this is currently being investigated.”


Dr Michael Head, Senior Research Fellow in Global Health, University of Southampton, said:

“This is a silver lining of comfort to the least merry Christmas in recent memory.  It is important to remember that the UK currently has a frighteningly-high burden of COVID-19 disease, and thus approaches to suppress the virus must remain in place across the next few months, whilst the vaccines are rolled out across the country.  The revised timings for dose 2 across both Pfizer and Oxford-AstraZeneca vaccines are an attempt to get as many people partially-protected as possible with dose 1, before following up with the second dose at a minimum of 21 days later.  This should reduce the number of severe COVID-19 cases and thus alleviate the burden on hospitals.

“The storage of this Oxford vaccine at refrigeration temperatures and the much lower cost of around $2-3 per dose will facilitate a more rapid roll-out across low- and middle-income settings.  This is a pandemic of inequalities.  Given how rapidly COVID-19 spread around the world, the pandemic will not end until much of the world is vaccinated.”


Dr Clive Dix, Chair of UK Vaccine Taskforce, said:

“Today is huge moment for the scientists and researchers involved in this vaccine and is a result of many years of hard work and late nights – I thank them all for their grit and determination.

“We recognised the significance of the Oxford University / AstraZeneca vaccine right from the start, which is why it was the first vaccine in our diverse portfolio with the UK being the first country to sign an agreement for 100 million doses, and why we fully-backed their clinical trials.

“The Oxford University / AstraZeneca vaccine stands out on the global stage because it is being made on a not-for-profit basis and will be available to some of the world’s most vulnerable populations.  This is an ethos the Vaccines Taskforce shares and we are determined to ensure the fair and equitable access to vaccines across the globe regardless of status and influence.”


Dr Richard Hatchett, CEO of CEPI, said:

“We were delighted to hear today’s (30 December) announcement that the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) has granted emergency authorisation for the University of Oxford/ AstraZeneca COVID-19 vaccine.

“MHRA’s determination that the University of Oxford /AstraZeneca COVID-19 vaccine is safe and effective paves the way, we hope, for similar determinations by other stringent regulatory authorities and for WHO Prequalification in the days and weeks ahead.

“The Oxford /AstraZeneca COVID-19 vaccine is extremely attractive in that it is inexpensive, scalable, and can be stored at 2-8 degrees Celsius.  These attributes will enable its use worldwide, including in low-income and middle-income countries, alongside other safe and effective COVID-19 vaccines, and the large supplies that will become available in 2021 mean that this vaccine could be a gamechanger in terms of our efforts to end the acute phase of the pandemic.

“Today’s authorization of a vaccine based on viral vector technology, as opposed to the mRNA approach employed by the Pfizer and Moderna vaccines, solidifies our belief that we will soon have a diverse array of vaccines with which to fight this devastating pandemic.

“CEPI’s earlier investments with the University of Oxford supporting the development of this

technology for use against other epidemic diseases—most notably the Middle East Respiratory Syndrome, or MERS, which is caused by another coronavirus—positioned us to move at speed to meet this new threat as the COVID-19 pandemic accelerated earlier this year.

“COVAX agreements with University of Oxford and AstraZeneca and other manufacturers that were announced on 18 December ensure that we have a clear pathway forward to securing 2 billion doses for the populations at greatest risk around the world.

“To have multiple vaccines authorized before the end of 2020 is truly remarkable.  This is an extraordinary moment in the history of vaccinology but also medicine more generally.  What is critical now, especially in light of the emergence of new strains of COVID-19 with increased transmissibility, is that we continue to scale up and scale out production of successful vaccines to ensure that they are made available globally without delay.  We must also continue to invest in vaccine R&D—specifically next-generation vaccine candidates—to ensure we have the tools to meet the needs of all segments of all populations in all countries for the long term.”


Dr James Gill, Honorary Clinical Lecturer, Warwick Medical School, said:

“The release and authorisation of a second COVID-19 vaccination should be heralded as a major advance with regard to combating the current pandemic, especially as there is the spectre of further tier 4 restrictions in response to the spread of the new variant of COVID-19 out of the south-east.

“In broad terms, the Pfizer vaccine, provides a mRNA blueprint to educate the immune system as to what it needs to fight against.  By contrast the Astrazeneca vaccine shows the immune system a deactivated version of the common cold dressed up to look like COVID-19 as far as our immune system is concerned.  The team at the Jenner Institute have designed a dummy for the immune system to learn and practice against so the body is able to fight COVID-19.  Looking at the results released from the AstraZenica trails it appears as though the Oxford vaccine is providing a very robust response from the immune system.  Let’s hope this immune system training pays off, and as both vaccines are rolled out further we start to turn the tide in this pandemic.”


Prof Helen Fletcher, Professor of Immunology London School of Hygiene & Tropical Medicine, said:

“Approval of this vaccine is a turning point for the pandemic because it has been deliberately developed to have global impact that includes people living in the most fragile and poorest regions of the world.  With more than 30 supply agreements and partner networks established globally the Oxford/AstraZeneca vaccine could slow the pandemic and should save many lives within the next year.

“The published trial data from Voysey et al did suggest early protection against SARS-CoV-2 following the first standard dose ChAdOx1 nCoV-19 vaccine, although the numbers in this secondary analysis of the data were small.  The published study also looked at timing between first and second dose and there was no evidence of reduced efficacy in those with a greater than 6 week interval between first and second dose – so the data are consistent with the JCVI recommendation to give as many at-risk people their first dose as possible.”


Prof Arne Akbar, President of the British Society for Immunology, said:

“The approval of the Oxford University/AstraZeneca COVID-19 vaccine is brilliant news and an extremely positive step forward in our ability to control this pandemic.  It is only 12 months ago that we first learnt about the emergence of the SARS-CoV-2 virus.  To have developed a safe and effective vaccine in that time is nothing short of remarkable.

“The Medicines and Healthcare products Regulatory Authority (MHRA) will have carefully scrutinised the evidence on this COVID-19 vaccine to ensure that it is both safe and effective.  Although development of this vaccine has occurred quickly, all the same rigorous safety standards and checks have still been carried out.  Indeed, we already have much of that evidence in the public domain from December’s The Lancet paper (  From the data presented in that paper, the vaccine showed a good safety profile and no individual who received the vaccine subsequently suffered from severe COVID-19.

“There is now much work to do to roll out this vaccine across the country at the speed required and we need to support our dedicated healthcare professionals in the logistical challenges ahead.  Additionally, we must build public confidence in the vaccine to ensure high uptake.  We urgently need a high-profile, multifaceted engagement campaign that listens and responds to the public’s questions around the vaccine.

“COVID-19 is a global pandemic, which means to stop the spread of the disease, we must have vaccines that can be easily rolled out to all countries.  The University of Oxford/AstraZeneca COVID-19 vaccine brings the added benefit that it can be stored and transported at fridge temperature, meaning that it can utilise existing delivery mechanisms to be rolled out to all countries in the world much easier.

“The UK leads the world for the quality of our immunology research.  We should be extremely proud of the University of Oxford team and their international collaborators for the monumental work they have carried out to develop a safe and effective vaccine so quickly.  We also owe a huge debt of gratitude to the many thousands of people who volunteered to take part in this vaccine trial.  They have played a critical role and we would not be able to have developed a vaccine so quickly without them.” 


Richard Torbett, Chief Executive of the ABPI, said:

“It’s great news that today we have another vaccine approved by the MHRA to help fight COVID-19.

“The world needs multiple vaccines to bring an end to the pandemic.  In what has been a difficult year, it’s fantastic to see another scientific collaboration coming to fruition.”


Prof Stephen Evans, Professor of Pharmacoepidemiology, London School of Hygiene & Tropical Medicine, said:

“This is the very good news for the world that we have been expecting.  Authorisation of this vaccine, with usual cold-chain requirements, will mean that a global approach to the global pandemic becomes easier.  There is little doubt that this vaccine has more than enough efficacy to allow for it to be authorised based on the randomised trial data that have been published.  Further follow-up data both on efficacy and the absence of serious harms (safety) will have been made available to the regulatory authority and we can be assured that all data will have been scrutinised.

“The separate decision by the UK body responsible for setting policy in its use, the Joint Committee on Vaccination and Immunisation (JCVI), to allow both the currently UK authorised vaccines to be given with a greater delay between doses to maximise the numbers getting one dose as rapidly as possible is a sensible one.  It cannot have been an easy decision, since the evidence on the efficacy of one dose was more limited, but the crisis in the UK requires more than the usual regulatory approach.

“This will not bring a rapid return to life as it was before Covid-19, but is a very major step on the way.  Recipients of the vaccine will still have to follow distancing, hand-washing and other non-medical interventions to protect themselves and those around them.  No vaccine is 100% effective and behaving as if it were, will serve to prolong the pandemic.

“The availability of large numbers of doses both in the UK and, via various funding mechanisms, for lower-income countries is of enormous importance.

“We can look forward to other vaccines accruing data that will extend the options available globally, and we should hope that the necessary trials, perhaps involving different designs, will be able to be completed.”


Prof Robert Read, Head of Clinical and Experimental Sciences within Medicine at the University of Southampton, and Director of the NIHR Southampton Biomedical Research Centre, said:

“This is a tremendous day for all of us.  With the approval of the AZ vaccine it means that we can vaccinate at scale with the priority for the first phase being those who are vulnerable to severe disease and hospitalisation.  The impact will take a few weeks to be seen but I am certain it will be significant.

“MHRA approval means that a team of qualified scientists have scrutinised the clinical trial and safety data and concluded that the vaccine is safe for deployment and has the efficacy claimed by the manufacturer.  MHRA gave approval for a 2 dose course.

“JCVI has advised the government that the vaccines can be deployed in a way that reaches as many people as possible as quickly as possible, with the emphasis on getting the first dose into vulnerable groups at speed.  JCVI has advised that whilst we should be prepared to give people the second dose, it is acceptable to give that within 12 weeks of the first dose.  This allows some much needed flexibility in a programme as big as this.”


Prof Paul Hunter, Professor in Medicine, The Norwich School of Medicine, University of East Anglia, said:

“In my view the evidence for delaying the second dose of vaccine to enable as many as people as possible to receive the first dose sooner this is clear.  The evidence for this clear from the published report of the Phase 3 trial of the Pfizer vaccine the rate of new cases occurring dropped markedly in the vaccine group compared to the control from 12 days after the first dose (Figure 3, though the quoted efficacy “After dose 1 to before dose 2” includes cases from the first 12 days when there was no apparent effect so under-estimates efficacy after 12 days post first dose)1.

“The evidence for the beneficial effect of a single dose for the Oxford vaccine is somewhat less clear at least from publicly available data.  Graphs of cumulative incidence of primary symptomatic COVID-19 contained in the appendix only start 14 days after the second dose.  So I cannot find data that could allow efficacy calculations before the second dose an graphs in the appendix2.  Nevertheless, what data there is does support extending the time to second dose.  For hospitalisation (a pretty reliable indicator for severe disease) there does appear to be benefit from a single dose (Table 5)2.  In the placebo group there were 6 hospitalisations in the control group and 2 in the vaccine group between 1 and 21 days after the first injection.  However, of the two hospitalisations in the vaccine group both were before day 12, though we do not know how many of the 6 control hospitalisations were also before day 12 so we cannot estimate the post day 12 efficacy for hospitalisations and with such small numbers any confidence intervals are likely to be wide.  But it is clear from table 3 that the ultimate protection of immunisation is not reduced if the second injection is postponed beyond 8 weeks.

“There is also evidence from animal experiments.  For example, Wu et al recently showed with another adenoviral vector vaccine (not the Oxford AstraZeneca one) that a single dose in ferrets did provide protection up to at least 8 weeks when the experiment was completed3.

“So I welcome the news that second doses will be delayed to enable more people to have their first dose sooner and with the rapidly spreading new variant, I have no doubt this decision will save many lives.  But everyone will still need a second dose eventually to ensure that the protective effects of these vaccines lasts.”

1. Polack FP, Thomas SJ, Kitchin N, Absalon J, Gurtman A, Lockhart S, Perez JL, Pérez Marc G, Moreira ED, Zerbini C, Bailey R. Safety and efficacy of the BNT162b2 mRNA Covid-19 vaccine. New England Journal of Medicine. 2020 Dec 10.

2. Voysey, M., Clemens, S.A.C., Madhi, S.A., Weckx, L.Y., Folegatti, P.M., Aley, P.K., Angus, B., Baillie, V.L., Barnabas, S.L., Bhorat, Q.E. and Bibi, S., 2020. Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK. The Lancet.

3. Wu S, Zhong G, Zhang J, Shuai L, Zhang Z, Wen Z, Wang B, Zhao Z, Song X, Chen Y, Liu R. A single dose of an adenovirus-vectored vaccine provides protection against SARS-CoV-2 challenge. Nature communications. 2020 Aug 14;11(1):1-7.


Prof Ian Jones, Professor of Virology, University of Reading, said:

“More glad tidings!  Anyone and everyone will be happy to know that the independent MHRA has found the updated data package provided in support of the Oxford-AstraZeneca vaccine sufficient to warrant approval.  A level of immunity sufficient to prevent severe disease can be generated after only one inoculation of this vaccine so the revised JCVI advice to prioritise giving those at risk their first dose is a sensible idea.  It will allow more people in this group to treated with initial supplies, reduce the threat of hospitalisation from Covid-19, and accelerate the return to normality.”


Prof Trudie Lang, Director, The Global Health Network, Nuffield Department of Medicine, University of Oxford, said:

“The approval of the University of Oxford / AstraZeneca vaccine is tremendous step forward in the collective global effort to get every nation beyond the devastating health and economic impact of COVID-19.

“Global equity in access to a safe and effective vaccine is a collective responsibility and many countries have signed up to achieving this through the COVAX initiative.  We now hope that approval of this vaccine in the UK is rapidly followed by regulatory authorities across the globe so that enacting these pledges now becomes reality.  This is more feasible because this vaccine can be stored and transported at normal refrigeration temperatures and is being manufactured in many sites across the world.

“Approval of another COVID-19 vaccine is a remarkable and incredible scientific achievement in such a short time.  This vaccine offers the real possibility of a route out of the catastrophic impact that this pandemic is having within the most vulnerable communities across the world, if collaboration and a global shared effort can ensure fair supply and uptake.”


Prof Chris Whitty, Chief Medical Office for England and co-lead of the National Institute for Health Research, said:

“It is very good news that the independent regulator has now authorised for use the Oxford/AstraZeneca vaccine.  There has been a considerable collective effort that has brought us to this point.  The dedication and hard work of scientists, regulators and those who funded the research, such as the National Institute for Health Research (NIHR), United Kingdom Research and Innovation (UKRI) and United Kingdom Vaccine Network (UKVN), and the willingness and selflessness of so many volunteers who took part in the vaccine trials were essential in delivering this safe and effective vaccine.  They deserve our recognition and thanks.”


Prof Daniel Altmann, Professor of Immunology, Imperial College London, said:

“This is the fruition of decades of ground-breaking vaccinology and hard graft by the team at the Jenner in Oxford.  It couldn’t be more timely and desperately needed.  At a time when we see the pandemic accelerating beyond our control, a rapid, efficient vaccination programme with good population coverage is our only way out.  This vaccine induces good levels of neutralising antibodies and T cells.  With two vaccines now in the roll-out and  very substantially more doses, it starts to look realistic that this could be achievable by the Spring or early Summer.”


Prof Lawrence Young, Professor of Molecular Oncology, Warwick Medical School, said:

“Approval of the Oxford-AstraZeneca COVID-19 vaccine provides a ray of hope at the end of a very challenging year.

“It also comes at a time when we have just recorded the largest daily increase in the number of infections in the UK and when the NHS is struggling with the number of hospitalisations.  And all this on the backdrop of a more infectious variant of the virus.

“So this approval by the MHRA for emergency use of the vaccine is great news and couldn’t come at a better time.  We await the latest advice from the Joint Committee on Vaccination and Immunisation (JCVI) on the priority for vaccination.  To maximise the number of at-risk groups receiving the vaccine, the first dose will be given to as many people as possible with the second dose being delayed for up to 12 weeks.  This will allow the 100 million vaccine doses ordered by the UK government to be rolled out to as many people as possible starting as soon as next week.”


Prof Ravindra Gupta, Professor of Clinical Microbiology, University of Cambridge, said:

“The news of emergency use authorisation for the Oxford vaccine could not have been more timely given the acceleration in transmission and the new variant of concern bearing multiple mutations.  The plan to give as many first doses as possible is sensible but NHS staff need to be prioritised because sickness in NHS staff will ultimately cost lives during this winter crisis.  We must also target vaccination to control transmission and bolster social restriction measures.  The efficacy of the vaccine should also be thoroughly tested by prospective study, in particular the protection offered against both the B1.1.7 variant and other circulating viruses.”


Prof Dame Ottoline Leyser, Chief Executive, UK Research and Innovation, which helped to fund the vaccine, said:

“MHRA approval for the Oxford vaccine is such good news on which to end the year.  This is a safe and affordable vaccine that is easily distributed at fridge temperature.  It has a key role to play in saving lives worldwide.

“This is the culmination of a year of dedicated hard work, but the work will continue to understand better the immunity the vaccine confers, the most effective dosage regimes, and to continue to track its safety, duration of effectiveness and impact on transmission.”


Prof Fiona Watt, Executive Chair of the Medical Research Council, which helped to fund the vaccine, said:

“By moving swiftly to approve the vaccine, the MHRA have ensured that a safe and effective route to halting the pandemic is available to the UK population.”



All our previous output on this subject can be seen at this weblink:



Declared interests

Prof Saad Shakir: “The Drug Safety Research Unit is an independent charity (No. 327206), which works in association with the University of Portsmouth.  It receives unconditional donations from pharmaceutical companies.  The companies have no control on the conduct or the publication of the studies conducted by the DSRU.

Saad Shakir is an employee of Drug Safety Research Unit, an independent charity (No. 327206), which works in association with the University of Portsmouth.  He has no conflicts of interest to declare.”

Dr Gillies O’Bryan-Tear: “No conflicts.  Former Head of Vaccine Clinical Development, GSK.  I am a pharmaceutical physician, semi-retired and have worked in a variety of fields, including oncology (cancer) drug development and vaccines development.  I have not been active in vaccine research for many years and have no current interests in or conflict with any of the Covid-19 vaccine research programmes.”

Dr Michael Head: “No conflicts of interest to declare.”

Dr Richard Hatchett: “CEPI’s partnership with University of Oxford and AstraZeneca:

In 2018, CEPI partnered with the University of Oxford and Janssen Vaccines to advance the development of vaccines against diseases of epidemic potential – MERS, Lassa fever and Nipah.

In March 2020, CEPI provided the University of Oxford with catalytic funding to support the manufacture of vaccine materials required for preclinical and Phase I testing of their COVID-19 vaccine candidate.

In June 2020, CEPI expanded its partnership with University of Oxford and AstraZeneca in June to manufacture doses for distribution through the COVAX Facility.

In Dec 2020, COVAX, co-led by CEPI, Gavi, and the WHO, announced a number of updates to the initiative, including the signing of an advance purchase agreement with AstraZeneca for 170 million doses of the Oxford/ AstraZeneca vaccine. This deal is in addition to existing agreements COVAX has with the Serum Institute of India (SII) for manufacture of 200 million doses – with options for up to 900 million doses more – of either the Oxford/AstraZeneca or Novavax vaccines, via an agreement between Gavi, the Serum Institute of India, and the Bill and Melinda Gates Foundation.”

Dr James Gill: “Nothing on vaccines but on Medical advisory board for Wiseprotec.”

Prof Helen Fletcher: “Trustee of the Jenner Vaccine Foundation, Director of International Development, UKRI.”

Prof Arne Akbar: “Receives funding form the Medical Research Council, The Leo Skin Foundation (Denmark), The British Skin Foundation and Dermatrust.”

Richard Torbett: “No conflicts of interest.  The ABPI is the trade body that represents research-based pharmaceutical companies in the UK, but it has no link to the development of any treatment or vaccine by any of its members.”

Prof Stephen Evans: “No conflicts of interest.  I am funded (one day per week) by LSHTM.  They get funding from various companies, including Astra Zeneca and GSK but I am not funded by them, I have no involvement in obtaining funding from them and I am not an investigator on any grants obtained from them.  I am the statistician to the ‘meta-Data Safety and Monitoring Board’ for CEPI.  I am paid for my attendance at those meetings and will be paid expenses for travel if that occurs.  I am a participant in the Oxford/Astra Zeneca trial, but am still “blind” to the vaccine received.”

Prof Robert Read: “I am a member of JCVI.  I have no conflicts.”

Prof Ian Jones: “No conflicts.”

Prof Trudie Lang: “I work at the University of Oxford, but in a different group to the Oxford Vaccine team.”

Prof Daniel Altmann: “None.”

Prof Lawrence Young: “No conflicts of interest.”

Prof Ravindra Gupta: “No disclosures.”

None others received.

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