When a coronavirus vaccine might be available after initial trial creates an immune reaction

The findings from a potential coronavirus vaccine trial have been celebrated, with Boris Johnson deeming it a ‘step in the right direction’. 

Scientists at the University of Oxford have revealed they are currently working on a vaccine that is safe and induces an immune reaction. 

Researchers around the world are racing to develop a vaccine against COVID-19 with the World Health Organisation following the development of over 140 candidate vaccines.

Professor Sarah Gilbert from Oxford said that after intensive research they were ‘more than happy with the first results’. 

She told the Guardian:  “We’re really pleased that it seems to be behaving just as we thought it would do. We have quite a lot of experience of using this technology to make other vaccines, so we knew what we expected to see, and that’s what we have seen.” 

While Boris Johnson explains this as ‘very positive news’ he added:  “There are no guarantees, we’re not there yet and further trials will be necessary – but this is an important step in the right direction.”

Matt Hancock said: “Very encouraging news. We have already ordered 100 million doses of this vaccine, should it succeed.”

Despite this, Professor Gilbert and her colleagues will not predict when the vaccine will be available, explaining ‘none of us have a crystal ball’. 

While the lockdown drastically reduced the circulation of COVID-19 and saved many lives it also made it very difficult to trial vaccines. 

The study released the results on Monday, which involved 1,000 healthy volunteers half of which were given the vaccine and half were given meningitis vaccine. 

The results were a ‘really important milestone’ according to Professor Andrew Pollard, lead author on the study. 

He added: “We are seeing exactly the sort of immune responses we were hoping for, including neutralising antibodies and T-cell responses, which, at least from what we’ve seen in the animal studies, seem to be those that are associated with protection.

“We just don’t know what level is needed if you meet this virus in the wild, to provide protection, so we need to do the clinical trials and to work that out.”

Pollard added that researches should be able to find out this from the vaccine trails which will help vaccine developers.

He explained: “We don’t know what high is. We’ve got immune responses that we can measure, we can see the virus being neutralised when the antibodies are tested in the laboratory, but we don’t know how much is needed. I mean it’s encouraging but it’s only the first milestone on this long path.”

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While some scientists are hopeful that a vaccine could be ready by autumn, others have avoided speculation over when it could be available at this early stage.

Pascal Soriot, the chief executive of AstraZeneca, which is the pharmaceutical company that developed the vaccine alongside the Oxford scientists, has said that if successful, the vaccine could be distributed as early as the end of 2020.

He told reporters: “We’re working as quickly as we can but of course there are things that we cannot control, in particular the infection rate in the community which influences the results. We’re basically starting the manufacturing process in parallel to running the clinical trials.

“Our hope is that we can actually start delivering the vaccine before the end of the year, and how early before the end of the year depends really on infection rates in the community.”

This was backed up by Kate Bingham, the UK Vaccine Taskforce’s chairwoman, who told BBC Radio 4’s Today programme ‘optimistically we will be vaccinating by the end of the year’, before adding that she wouldn’t ‘go to the bank on it yet’.

In an ideal world, the coronavirus vaccine will help fight any risk of infection however scientists have already accepted that instead, the vaccine will reduce the severity of the disease instead and in turn reduce the risk of death. 

A further question is how long any immune response will last and how regularly people will need booster shots. 

However, Gilbert explains that the work so far suggests this will not be a problem. The vaccine is delivered in an inactivated chimp adenovirus (similar to the common cold in humans) and there have been concerns that this might be recognised and rejected by the immune system. 

“We actually show in the paper that there are some antibodies that develop against the vaccine vector itself – against the adenovirus – it doesn’t stop the vaccine from boosting,” she said.

There are also other questions as to the success rate of the vaccine on older adults. Safety trials have already begun in two groups of adults, one in 56-69 and the other in over-70s, says Gilbert. 

“The immune system has two ways of finding and attacking pathogens – antibody and T-cell responses. This vaccine is intended to induce both, so it can attack the virus when it’s circulating in the body, as well as attacking infected cells,” said Pollard.

“We hope this means the immune system will remember the virus, so that our vaccine will protect people for an extended period. However, we need more research before we can confirm the vaccine effectively protects against Sars-CoV-2 infection, and for how long any protection lasts.”

Other scientists have cautiously welcomed the study in a similar response to a second paper published in Lancet which showed trials of Wuhan of a vaccine developed in China. This used a similar process, using a human adenovirus vector showed it was also safe and generated an immune response. 

Head of global policy and advocacy at the research charity Welcome Trust, Alex Harris said the Oxford University result was “just one crucial step but it’s very encouraging, and builds on the incredible global research effort during this crisis.

“To see promising results from several candidates in months is remarkable, but we must also be prepared for some candidates to fail in the later stages and be realistic about time frames for manufacturing and roll-out.”