New study into COVID-19 vaccine dose interval for pregnant women

  • New government-funded clinical trial investigating best COVID-19 vaccine dose interval for pregnant women launched in England
  • Research shows pregnant women more likely to become seriously ill from COVID-19 and 98% of those in hospital due to COVID-19 are unvaccinated

The UK’s largest clinical trial investigating the best gap between first and second COVID-19 vaccine doses for pregnant women is being launched in England today (Tuesday 3 August).

Following 130,000 pregnant women being vaccinated in the US and no safety concerns being raised, the Pfizer/BioNTech and Moderna vaccines were recommended by the independent experts at the Joint Committee on Vaccination and Immunisation (JCVI) for pregnant women in the UK.

Almost 52,000 pregnant women in England have now been vaccinated – again, with no safety concerns reported.

Data published last week by NHS England and the University of Oxford also shows no pregnant women who have had both doses of a vaccine have been admitted to hospital with COVID-19. Only three have been admitted after having their first dose, meaning 98% of those admitted to hospital have not received a jab.

The Preg-CoV study, backed by £7.5 million of government funding and led by St George’s, University of London, will provide vital clinical trial data on the immune response to vaccination at different dose intervals – either four to six weeks or eight to 12 weeks.

This data will help determine the best dosage interval and tell us more about how the vaccine works to protect pregnant mothers and their babies against COVID-19.

Minister for COVID-19 Vaccine Deployment Nadhim Zahawi said: “Pregnant women are more likely to get seriously ill from COVID-19 and we know that vaccines are safe for them and make a huge difference – in fact no pregnant woman with two jabs has required hospitalisation with COVID-19.

“This government-backed trial will provide more data about how we can best protect pregnant women and their babies, and we can use this evidence to inform future vaccination programmes. I encourage anyone who is pregnant and eligible to sign-up and contribute to research that will save lives for years to come.”

Vaccines have been given to pregnant women to protect them and their babies from diseases for years – including for whooping cough and flu.

The trial will involve over 600 pregnant women being vaccinated with either the Pfizer/BioNTech or the Moderna vaccine. They will be closely monitored by health professionals throughout their pregnancy and following the birth, with the safety of the women taking part in the trial the utmost priority.

The Preg-CoV participants will need to be between 18 and 44 years old, have no health conditions and be between 13 and 34 weeks pregnant on the day of vaccination. They will receive two doses of a COVID-19 vaccine – or one dose if they’ve already had their first – at either the shorter interval of four to six weeks, or the longer interval of eight to 12 weeks.

They will be scheduled to attend nine visits in total and will be required to complete an electronic diary between visits on any symptoms. They will also be given a 24-hour mobile number so they can contact one of the trial team at any time if they have concerns.

The scientists behind the trial will analyse blood samples from the participants and one blood sample from their newborn babies, alongside samples from breastmilk. They will use the samples to help understand more about how the vaccines are protecting these individuals from COVID-19, with initial results expected by the end of the year.

The study will open for applications from volunteers today via the study’s website, with vaccinations set to start from mid-August. Participants will also be recruited to the study by invites sent through the NHS COVID-19 Vaccine Research Registry, which allows research teams to speak to suitable volunteers who have signed up to be contacted about taking part in vaccine studies.

Chief Investigator and Professor of Paediatric Infectious Diseases at St George’s, University of London, Professor Paul Heath said: “Tens of thousands of pregnant women have now been vaccinated in both the US and the UK with no safety concerns reported, but we still lack robust, prospective clinical trial data on COVID-19 vaccines in pregnant women. This includes the best schedule to use to maximally protect them against COVID-19.

“We are extremely pleased to commence the Preg-CoV trial, which aims to fill these gaps in our knowledge and will ultimately inform policy recommendations on the optimal use of COVID-19 vaccines in pregnancy.

The trial will be run across 13 National Institute for Health Research (NIHR) sites in England – including in London, Liverpool and Leeds. All the trial sites are working on ways of including participants from a wide variety of backgrounds and individuals from ethnic minorities are encouraged to apply.

The vaccination programme continues its phenomenal progress towards vaccinating the adult population of the UK, with over 85,336,436 vaccines administered in total – 46,872,411 first doses (88.6%) and 38,464,025 second doses (72.7%).

Further analysis from PHE and the University of Cambridge also suggests vaccines have so far prevented over 52,600 hospitalisations, an estimated 22 million infections and more than 60,000 deaths in England alone.

Dr Pat O’Brien, Vice President of the Royal College of Obstetricians and Gynaecologists, said: “We now have robust data of nearly 200,000 women from across the US and the UK, who have received the COVID-19 vaccine with no safety concerns.

“This tells us that both the Moderna and Pfizer vaccines are safe in pregnancy. However, more research is needed to monitor and understand how pregnant women respond to the COVID-19 vaccine.

“We welcome this trial as the next step in further monitoring the protection provided by the vaccine, to understand the risk of any potential adverse side effects, and observe the immune response within those who are pregnant and their babies.

“We encourage all pregnant women to get vaccinated, as the protection that it provides against COVID-19 to both mother and baby outweigh the risks. We are seeing more pregnant women being admitted to hospital with COVID-19, and we know that the Delta variant is causing more pregnant women to have severe illness than previous strains of the virus.

“We hope that this research will help to gain the confidence of pregnant women that the recommendation of vaccination in pregnancy is based on robust evidence.”

Professor Nick Lemoine, Medical Director, NIHR Clinical Research Network, said: “The fact that every participant in this study receives an approved vaccine will give volunteers peace of mind that they are protected from the virus and that they can take confidence in the safety of these vaccines, and the monitoring involved in the study.

“Vaccine studies like this remain crucial for researchers to gain more information on the best intervals and methods to help protect the whole population against COVID-19.

“It is thanks to the continued dedication and commitment of volunteers that we are at this stage of research and the NIHR is very grateful for their efforts.

“The NHS COVID-19 Vaccine Research Registry continues to help us reach out to potential participants and recruit to additional studies as we keep moving forward, and we encourage interested members of the public to sign up to be contacted at nhs.uk/ResearchContact.”

Volunteers can sign up to the trial here

Study finds COVID-19 vaccines are ‘highly effective’ in most people in clinical risk groups

Those used in the UK as effective at preventing symptomatic disease in the majority of people with underlying health conditions as the rest of the population

The study from Public Health England (PHE) included more than 1 million people in at-risk groups.

Within these clinical risk groups, there will be people with more severe forms of illness – particularly in the immunosuppressed group – who may not respond as well to the vaccines, and we recommend they seek advice from their specialists.

The study found:

  • overall vaccine effectiveness against symptomatic disease in risk groups is approximately 60% after one dose of either AstraZeneca or Pfizer-BioNTech, with little variation by age
  • after 2 doses, vaccine effectiveness is 81% with AstraZeneca in people in risk groups aged 16 to 64. No data is available for Pfizer-BioNTech
  • in people in risk groups aged 65 and over, vaccine effectiveness with Pfizer-BioNTech is 89% and 80% with AstraZeneca
  • for those who are immunosuppressed, vaccine effectiveness after a second dose is 74%, with similar protection to those who are not in a risk group. This rises from 4% after a first dose

Although age is the greatest risk factor for adverse outcomes following coronavirus (COVID-19) infection, certain health conditions also increase the risk of severe disease.

Diabetes, severe asthma, chronic heart disease, chronic kidney disease, chronic liver disease, neurological disease, and diseases or therapies that weaken the immune system – such as blood cancer, HIV or chemotherapy – have all been linked to an increased risk of hospitalisation or death with COVID-19.

People with these conditions who are at highest risk were initially advised to shield during the peak of the pandemic and all risk groups were then prioritised for vaccination. The government announced the dose interval would be brought forward from 12 to 8 weeks for the clinically vulnerable on 14 May, and everyone in these groups should now have been offered a second dose.

Data on vaccine effectiveness among people in clinical risk groups was previously limited. Though more data is needed, protection against hospitalisation and death in risk groups is expected to be greater than protection against symptomatic disease, as has been seen in studies of the general population.

Dr Mary Ramsay, Head of Immunisation at PHE, said: “This real-world data shows for the first time that most people who are clinically vulnerable to COVID-19 still receive high levels of protection after 2 doses of vaccine.

“It is vital that anyone with an underlying condition gets both doses, especially people with weakened immune systems as they gain so much more benefit from the second dose.”

The Joint Committee on Vaccination and Immunisation (JCVI) advised that those living with immunosuppressed adults should be prioritised for vaccination to help limit the spread of the virus to people in this group.

If the planned booster programme goes ahead, the JCVI has recommended that immunosuppressed adults and their household contacts should also be among the first to be offered a third dose of vaccine in September.

PHE estimates that 30,300 deaths and 8,151,000 infections have been prevented as a result of the COVID-19 vaccination programme, up to 25 June. This is based on modelling analysis from PHE and Cambridge University’s MRC Biostatistics Unit.

PHE also estimates that 46,300 hospitalisations have been prevented in people aged 65 or older in England up to 27 June (approximately 7,000 admissions in those aged 65 to 74, 18,000 in those aged 75 to 84, and 21,300 in those aged 85 and over).

Strokes caused by Covid-19 under the spotlight in world’s largest research study

The Stroke Association is funding the world’s largest research study to investigate worrying reports that Covid-19 is causing life-threatening strokes.

As Covid-19 cases continue to rise across the globe, this critical research may help to prevent Covid-19-related death and disability. The study will build on the work of the British Heart Foundation (BHF) Data Science Centre at Health Data Research UK (HDR UK).   

Announced today, the study uses health data from nearly all UK adults. Having access to large amounts of data will allow the researchers to follow the health of Covid-19 patients. Data analysts will compare stroke in patients who have tested positive for Covid-19 with patients without the virus, to confirm if Covid-19 increases risk of stroke and by how much.

The researchers will also analyse stroke risk and characteristics including age, sex, ethnicity and geography to identify which Covid-19 patients may be most at risk of stroke. Stroke risk due to Covid-19 will be compared to increases in stroke risk due to other infections and cardiovascular conditions.

Dr Rubina Ahmed, Research Director, Stroke Association said: “Stroke already strikes every five minutes and we’re extremely concerned that Covid-19 may lead to more strokes, destroying more lives.

“Equally concerning are reports that stroke patients who have Covid-19 may be younger, and experience more severe effects of stroke, including death [3]. Severe illness due to Covid-19 is a challenge enough– but it’s worrying that a deadly stroke might also be on the way. This new research can help guide the development of new treatments that can prevent life-threatening strokes.”

This research forms part of the CVD-COVID-UK flagship project consortium, which is led by the BHF Data Science Centre at HDR UK. This project consortium aims to understand the relationship between Covid-19 and cardiovascular diseases such as heart attack and stroke in the UK population.

Dr William Whiteley, Reader in neurology at the University of Edinburgh and a lead on this research said: “Covid-19 may cause stroke in some patients.  So far studies of Covid and stroke have been small. More data will improve our understanding and give a better idea of the risks of stroke after Covid-19 infection.

“With the funding of the Stroke Association and access to the data and research community brought together by the BHF Data Science Centre, the team can use health information from nearly all adults in the UK.

“By working with information specialists, we’ll be able to accurately detect even the smallest increase in risk of stroke across different groups of people. We’re incredibly grateful to have the support of charities to help get this urgent research underway, so that we can better inform patients and health care professionals about Covid-19 and risk of stroke.”

Dr Rubina Ahmed continues: “We will be living with Covid-19 for the foreseeable future and we don’t want to see the pandemic leave more deadly strokes in its wake. Stroke is a leading cause of adult disability in the UK and the second biggest killer in the world.

“This research is crucial to our understanding of Covid-19 and strokes, but this is just the tip of the iceberg. The Covid-19 pandemic has had a devastating impact on our income and is threatening life-saving breakthroughs. Now more than ever, we need the public’s support. If you can, please help us find a way through the research funding crisis by donating today, so that we can fund more life-saving research.”  

Juliet Bouverie, Chief Executive of the Stroke said: “We’ve been supporting stroke survivors throughout the pandemic through our Helpline and our Stroke Association Connect and Here For You services.

“Strokes changes lives in an instant and stroke survivors need support to recover, cope and adapt and those with Covid-19 may have additional needs. We need to be prepared with new knowledge about links between Covid-19 and stroke to support people affected by stroke long into the future.”

Prof Cathie Sudlow, Director of the BHF Data Science Centre at Health Data Research UK said: “The BHF Data Science Centre is delighted to be providing the scientific and data access infrastructure to enable this important Stroke Association-funded research project.

“We look forward to working with and supporting Dr Whiteley and his research team as they generate insights to help people with stroke, their carers and health professionals understand the impact of Covid-19 on stroke risk, and make informed decisions about their treatment and care.”

Over the past 30 years the Stroke Association has played a crucial role in supporting stroke research in the UK. This year, as a result of the pandemic the charity has had to halve its budget for stroke research.

To find out more about research funded by the charity visit stroke.org.uk/research or to donate please go to: stroke.org.uk/donate-research