What Are The Coronavirus Vaccine Human Trials Actually Doing And What Is Involved?

Experts involved in the Oxford University Covid-19 vaccine trial – and a participant – explain how it works.

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The nation has been given a glimmer of hope in the fight against coronavirus with the news that up to 30 million doses of a Covid-19 vaccine will be made available to the UK by September – if human trials by Oxford University prove successful.

Business secretary Alok Sharma said earlier this week that Oxford was one of the world’s forerunners in the race for a vaccine and that clinical trials were “progressing well” with all phase one participants having received their vaccine doses on schedule.

But what exactly is the coronavirus vaccine trial, what are scientists trying to find out and what do participants have to do as part of their involvement in their involvement in the clinical study?

What is the purpose of the human trial of the coronavirus vaccine?

The aim is to test a new vaccine against Covid-19 in healthy volunteers.

The study will assess whether healthy people can be protected from coronavirus with this new vaccine called ChAdOx1 nCoV-19.

It will also provide valuable information on safety aspects of the vaccine and its ability to generate good immune responses against the virus.

Who can take part in the human trial of the vaccine?

Up to 1,102 participants have been recruited across multiple sites in Oxford, Southampton, London and Bristol.

Volunteers must be aged between 18 and 55 and cannot have tested positive for Covid-19. They must be in good health and be based in one of the recruiting areas.

They must not be pregnant, intending to become pregnant, or breastfeeding during the study.

Participants cannot have previously taken part in a trial with an adenoviral (relating to this particular group of viruses) vaccine or received any other coronavirus vaccines.

Jack Sommers, 34, who is taking part in the Covid-19 vaccine trial.
Jack Sommers, 34, who is taking part in the Covid-19 vaccine trial.
Jack Sommers

Jack Sommers, 34, who lives in south-west London, volunteered for the trial the day after discovering he was being made redundant from his job.

He told HuffPost UK he realised he was the perfect candidate for the study and wanted to do something useful.

“I am healthy, have had an uneventful medical history and have had no symptoms of coronavirus,” he said. “And as I live alone, there is no risk of me infecting vulnerable people or frontline workers.

“I also only live a 10-minute walk away from St George’s Hospital in Tooting which is one of the sites for the trial so I knew taking part would be relatively easy.

“For me to take part seemed a no-brainer and I knew how important it was.”

Why are human volunteers needed for the trial?

Until now, this Covid-19 vaccine has only been tested on laboratory mice and other animal species and this trial is the first time it has been given to humans.

The vaccine was developed in less than three months by a team at Oxford University and, although there has been pre-clinical research, it needs to be tested on humans and data needs to be evaluated.

Scientists need to demonstrate the vaccine actually works and stops people getting infected with coronavirus before it can be rolled out to the wider population.

“When my grandkids ask: ‘What did you do during the Great Coronavirus Lockdown Grandad?’ I’ll be able to say: ‘I did this.’ It makes me feel I am doing something worthwhile.”

- Jack Sommers

“Without people willing to take part, new vaccines wouldn’t be developed,” said Jack.

“I know there are some theoretical risks, but I have the greatest faith in the doctors and scientists and feel safe in their hands.”

Jack added: “In years to come when we all look back and talk about this time and my grandkids ask: ‘What did you do during the great coronavirus lockdown grandad?’ I’ll be able to say: ‘I did this.’ It makes me feel I am doing something worthwhile.”

How does the trial work and what do participants have to do?

Half the volunteers taking part in the trial will be injected with the prospective coronavirus vaccine while the other half will be given a meningitis vaccine that will be used as a control for comparison.

Volunteers will not know which vaccine they have received.

Jack said: “I completely understand there needs to be a placebo in clinical trials and, for this study, they wanted something stronger which is why they have used the meningitis vaccine.

“As far as I am concerned, I’m quids in. Whichever jab I have received, I’ve either been vaccinated against coronavirus or meningitis.”

After filling in paperwork, giving blood and urine samples for testing and watching a safety video, Jack was accepted on the trial.

He returned to hospital to receive an injection in his shoulder, which he described as “exactly like getting your holiday jabs”.

Jack Sommers, 34, who is taking part in the Covid-19 vaccine trial.
Jack Sommers, 34, who is taking part in the Covid-19 vaccine trial.
Jack Sommers

Jack and the other participants were sent home with a thermometer and a measuring tape to measure any potential swelling of the injection site.

Participants were also asked to fill in an e-diary to record any symptoms they experience in the first seven days after receiving the vaccine and to report if they feel unwell over the following three weeks.

Jack reported experiencing a very mild throat tickle the day after the injection and, the next day, he had a slightly raised temperature.

He is now in the second week following the vaccination and simply logs on to the e-diary every day and answers two straightforward questions on whether he has symptoms.

“I only have to give any details if I feel anything different, but I haven’t as yet,” he said.

Jack will return back to the trial site one month on from to have tests.

There will then be another visit and check-up six months on from the injection and an optional one a year on from the vaccination.

Jack said: “The symptoms for me have been very mild so I have barely suffered any inconvenience to my life at all.

“I had to input my temperature into the online diary for the first week, but now all I have to do is spend about five seconds putting: ‘No, I don’t have any symptoms.’”

At the start of the trial, a separate small group of 10 volunteers were also recruited to receive two doses of the Covid-19 vaccine four weeks apart.

This is to assess different reactions to a second dosage and establish both safety and how the immune response differs from those receiving a single dose.

A file image of a doctor filling a syringe with a vaccine.
A file image of a doctor filling a syringe with a vaccine.
Meyer & Meyer via Getty Images

What is the vaccine being tested?

The vaccine being tested in this research study is called ChAdOx1 nCoV-19.

It is made from a virus (ChAdOx1), which is a weakened version of a common cold virus (adenovirus) that causes infections in chimpanzees. It has been genetically changed so that it is impossible for it to grow in humans.

Scientists are hoping to make the body recognise and develop an immune response to the spike protein on the outside of the virus to stop it entering human cells and so prevent infection.

The main focus of the study is to find out if this vaccine is going to work against Covid-19, ensure it won’t cause unacceptable side effects, and see if it induces good immune responses.

What happens next?

There are a lot of complex stages in vaccine development according to Sarah Gilbert, professor of vaccinology at Oxford University’s Jenner Institute.

She says they will increasingly immunise more people to check for safety and immune response to the vaccine in older people as well as younger ones.

This is particularly important because it’s the older population that we really need to protect with a vaccine,” she said. “But with vaccines in general you often get a lower immune response as the immune system ages. So, we need to find out how well this vaccine works in older people compared to younger people by measuring the immune response to the vaccination.”

Sarah Gilbert, professor of vaccinology at the Jenner Institute at Oxford University.
Sarah Gilbert, professor of vaccinology at the Jenner Institute at Oxford University.
University of Oxford

She said the research team would also be checking if the vaccine actually protects people against Sars-CoV-2, the virus that causes Covid-19.

“People don’t know which vaccine they’re having and, over time, as people become infected or have symptoms of coronavirus, they’ll come to us to get tested.

“When enough people have become positive for the coronavirus, the statisticians will look at which groups those people are in, to find out whether they are in the group that had the coronavirus vaccine, or whether all positive cases are in the group that had the meningitis vaccine.

“We’re hoping for the infections to happen only in the meningitis vaccine group. And if that’s the case we will then be able to say that this vaccine works, at least in the age range we have vaccinated, and we can then start expanding the studies and we can start to apply for emergency use licensure so that the vaccine can be used more widely.”

Will people in the UK get access to the vaccine first if it is successful?

The UK will be first in line for 30m doses of Oxford University’s coronavirus vaccine by September if it passes trials, business secretary Alok Sharma has said.

He announced a deal had been struck between Oxford University and pharmaceutical giant AstraZeneca meaning that 30m doses would be made available by September for the UK as part of an agreement to deliver 100m doses in total, if ongoing trials succeed.

“The UK will be first to get access,” said Sharma. “Once a breakthrough is made, we need to be ready to manufacture a vaccine by the millions.”

He also announced a further £84m in funding to accelerate the work currently being done in vaccine trials at Oxford University and at Imperial College.

Is there a chance the vaccine won’t work?

Despite putting considerable investment into vaccine development, the government has cautioned that an effective coronavirus vaccine may never be found.

Gilbert agrees that, while she believes the prospects of developing a workable vaccine are good, nothing is certain.

“Nobody can be absolutely sure it’s possible to produce a successful vaccine, that’s why we have to do trials to find out.

“I think the prospects are very good but, clearly, it’s not completely certain.”


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