A coronavirus vaccine developed by scientists at the University of Oxford is safe and triggers an immune response.
In trials involving over a thousand people, an injection of the potential vaccine produced antibodies and T-cells that can fight coronavirus.
While it is still too soon to know whether it will offer enough protection against the virus – with larger trials to follow – Boris Johnson welcomed the results, hailing it as “very positive news” and “an important step in the right direction”.
The vaccine – technically called ChAdOx1 nCoV-19 is made from a genetically engineered virus that causes the common cold in chimpanzees.
It has been heavily adapted so that it does not cause infections in people, and was made to resemble coronavirus by transferring the genetic instructions for the crucial ‘spike protein’ – which invades our cells – to the vaccine.
The result is that the vaccine ‘looks like’ coronavirus, meaning that the immune system can learn how to attack it.
Findings, published in The Lancet, showed that levels of T-cells peaked in participants 14 days after vaccination, and antibody levels peaked after 28 days. Neutralising antibodies were developed in 90 per cent of people after one dose.
‘A waiting game’
Prof Andrew Pollard, from the Oxford team, told the BBC: “We’re really pleased with the results published today as we’re seeing both neutralising antibodies and T-cells.
“They’re extremely promising and we believe the type of response that may be associated with protection.
“But the key question everyone wants to know is does the vaccine work, dose it offer protection… and we’re in a waiting game.”
There are some side-effects, however, with 70 per cent of people on the trial developing either a fever or headache. However researchers believe that this can be managed with paracetamol.
‘Still much work to be done’
Professor Sarah Gilbert, who is leading the Oxford team, said: “There is still much work to be done before we can confirm if our vaccine will help manage the Covid-19 pandemic, but these early results hold promise.
“As well as continuing to test our vaccine in phase-three trials, we need to learn more about the virus – for example, we still do not know how strong an immune response we need to provoke to effectively protect against Sars-Cov-2 infection.
“If our vaccine is effective, it is a promising option as these types of vaccine can be manufactured at large scale.
“A successful vaccine against Sars-Cov-2 could be used to prevent infection, disease and death in the whole population, with high-risk populations such as hospital workers and older adults prioritised to receive vaccination.”
The main purpose of this round of trials was to ensure that the vaccine is safe enough to give to people – it did not show whether it can prevent someone becoming ill.
More than 10,000 people will take part in the next stage of the trials in the UK, while it has also been expanded to other countries because levels of coronavirus here are low.
Some 30,000 people will be involved in the US, as well as 5,000 in Brazil and 2,000 in South Africa.
A similar Chinese vaccine, which has been undergoing trials, was also found to be safe, and produced an immune response. The US company Moderna has previously reached this stage with its proposed vaccine.