By Sian Bayley, Local Democracy Reporter

Throughout the pandemic researchers in South London have been hard at work testing out vaccines against coronavirus.

Based at St George’s University in Tooting, they have been carrying out trials of the Oxford vaccine, which is a step closer to being considered safe and effective.

Last week a paper published in medical journal The Lancet showed there were no early safety concerns and that the vaccine induces a strong immune response.

We caught up with the director of the university’s vaccine institute, Professor Paul Heath, to find out more about how the trials have been working and when we can expect to see a vaccine.

Starting trials at St George’s

“We were very much involved in the very early discussions around the Oxford Covid vaccine trial and the Oxford vaccine is by far the first vaccine to have come through and gone into humans, certainly in the UK,” said Professor Heath.

“This is because the Oxford team had experience of using similar vaccines against other infections such as the original SARS and MERS.

“We were expecting to be part of this upfront, but nonetheless a huge amount of rapid effort was required,” said Professor Heath.

“It was so frantic and, you know, at the same time we were all learning about, and continue to learn about, Covid disease itself.”

He added that many researchers were also sheltering, had sick relatives, or had developed Covid themselves and were recovering at home.

“So obviously Covid-19 itself was affecting the trial members as patients or as people too,” he said.

In the first phase of the trial, only the healthiest people were recruited to try out the vaccine.

This meant that a lot of people had to screen potential participants, both on the phone and in the clinics to make sure it was as safe as possible to try out the new vaccine on them.

“We were very dependent on other people helping us,” said Professor Heath.

“Our team was never big enough to do all of this work, so throughout the vaccine trial we’ve relied on staff who do not normally do vaccine trials, and many of whom do not normally do research.”

The Oxford vaccine study

When the first results came though last week, the team were “very pleased”.

“Of course we hadn’t ourselves seen any serious side effects among our participants, but we were only one centre, so it was entirely possible they would be occurring still,” said Professor Heath.

The team at St George’s also did not know if the vaccine was helping to produce an immune response until the latest results came through from the team at Oxford.

The next step in the trial, known as phase three, is designed to be more reflective of the population that ultimately will need to be vaccinated.

While the first phases only recruited healthy people, phase three will also use older age groups between 55 and 70, and people over the age of 70.

“That’s really important because we know that the risk of severe disease is higher in the older population. So it makes sense we now see whether this vaccine will protect them,” said Professor Heath.

“The second is the safety because it involves a much larger number of people, so we will get an even better understanding of the safety of the vaccine.

“Obviously with the early trial, even though it’s 1,000 subjects, very rare but serious adverse effects may not be seen with that number of people, but when it comes to 10,000 it may be that we start to see important and serious but rarer adverse effects, and that’s important for us to know.”

Deliberately infecting people with coronavirus

Many people have been left confused why the coronavirus vaccine trial does not deliberately give people coronavirus to test if vaccines work.

It is because there are various ethical issues, especially if someone gets really ill and there is no treatment, but it is not being ruled out completely.

Professor Heath said: “At this moment in time we are not there, but it remains an active discussion in the Covid-19 world.”

He explained that as the number of cases in the community declines because of social distancing, it is more difficult to see if the vaccine works, because trial participants are less likely to be exposed to the virus.

“On the one hand, we don’t want there to be much Covid disease, of course we want it to go away, but on the other hand we recognise that it is unlikely to go away, and therefore we do need a vaccine, and the only way of showing which vaccine can be used is to do this efficacy trial which relies on cases occurring.

“The human challenge concept is certainly one that’s being considered and the reasons for considering that will include that it is a much quicker way of working out whether a vaccine, or any treatment in fact, can work against Covid-19, because it’s all being done in a controlled setting, so you will know who has the disease and who won’t, and therefore can draw conclusions.”

However, “the obvious problem with Covid-19 is we don’t have yet have an effective treatment to give patients who get it, and potentially then might get severe disease,” said Professor Heath.

“It would be definitely preferred that challenge trials were only done when treatment can then be given to prevent severe disease happening in a recipient.”

But this may change as new treatments continue to be tested.

The Imperial vaccine study

In the meantime, a number of other coronavirus vaccines are being developed.

At St George’s, they are now getting ready to conduct phase one trials for the Imperial vaccine, involving healthy volunteers aged between 18 and 75.

Professor Heath explains that this vaccine works slightly differently from the Oxford one, as it uses a man-made chemical called mRNA, rather than another virus (known as an andenorvirus – like the common cold), which is used in the Oxford trial.

But both are designed to mimic the spike protein of Sars-Cov-2 virus – the virus that causes Covid-19.

When injected into people’s cells, it causes them to produce the spike protein and train their immune system to recognise it and produce antibodies to defend against it.

He says “it is a little hard to predict” when a vaccine may be ready to use, but he thinks we might hear more about the Oxford vaccine towards the end of this year or the beginning of next year, once the phase three trial finishes.

But trials in South Africa and Brazil, where there are many more cases, may show if the vaccine is effective or not at an earlier date.

There are also likely to be updates on how well the Imperial vaccine is working in the autumn when the results from phase one are published.

Next steps

“The ambition for the UK with Covid-vaccines is that there will be a number more Covid vaccine trials occurring, so we fully expect here at St George’s to be involved in at least several more,” said Professor Heath.

“They will be starting September time, so there will be plenty of trials occurring in South London, and plenty of potential for participants in Covid vaccine trials, and obviously we would welcome all-comers because we need lots of participants for all of these vaccines.”

Professor Heath added that it is important that the UK has large numbers of effective vaccines.

“Now whether that is one particular vaccine, or three, four or five different vaccines, it doesn’t matter. But we need to allow the opportunity to have as many vaccines as we can that are safe and effective.

“It may be that different vaccines are better in different populations, so it may be that there is a vaccine that is better for the elderly, and that’s the one chosen for that. There may be better ones for young people and so-on.

“It is a very exciting time and there is much work to be done.”

If you are interested in taking part in a vaccine trial, you can sign up on St George’s website at: https://vaccine.ac.uk/recruiting-studies/

You can also be notified of coronavirus vaccine studies near you on: https://bepartofresearch.nihr.ac.uk/vaccine-studies/

Pictured top: Researchers and clinicians in the St George’s Vaccine Institute.