The Oxford coronavirus vaccine could still be ready by the end of this year or early next year, the company developing it has claimed, despite trials being paused this week.
Pascal Soriot, the CEO of drug giant AstraZeneca, told an online event he thought vaccine development remained ‘on track’ but they would have to wait for permission from an independent safety panel before resuming research.
Trials were paused on Wednesday after a British woman who received the vaccine reportedly suffered transverse myelitis, or a swelling of the spinal cord.
The company has denied these claims, and said more tests are needed before a final diagnosis can be made.
The Government’s chief scientist, Sir Patrick Vallance, warned yesterday that a coronavirus vaccine may not be ready until after Christmas.
Oxford’s vaccine is one of nine candidates in the world to have reached stage three clinical trials, and has been earmarked as most promising by the World Health Organisation.
Millions of doses have been ordered by nations around the world, should the vaccine prove effective and safe to use.
The CEO of AstraZeneca, Pascal Soriot (pictured), said he still thought the vaccine would be ready by the end of this year
CEO Soriot said once the volunteer’s illness was diagnosed it would be submitted to an independent safety committee for review, which would decide whether trials can continue.
Answering questions on why research had been paused he said it was ‘very common’ for this to happen during clinical trials.
But he added: ‘The difference with other vaccine trials is, the whole world is not watching them, of course. They stop, they study, and they restart.’
An AstraZeneca spokesman yesterday denied claims that a British woman in the trials had suffered transverse myelitis, stating.
‘We can also confirm that there was a brief trial pause in July while a safety review took place after one volunteer was confirmed to have an undiagnosed case of multiple sclerosis, which the independent panel concluded was unrelated to the vaccine.’
The vaccine, called AZD1222, is being trialled in up to 60,000 patients, which Soriot said was ‘typical’ for trials and large enough for spotting side effects.
‘With this you are going to pick up very rare events.’ he said adding that a planned staggered launch, prioritising at-risk groups, would provide further assurance for the masses that are set to be covered by government plans at a later stage.
Volunteers have been recruited in the UK, US, Brazil and other countries in South America to trial the vaccine.
It uses a weakened version of the common cold adenovirus which has been engineered to carry the protein found on the outside of the coronavirus SARS-CoV-2.
Once participants are exposed to this protein, it is hoped it primes the immune system to mount a successful response if they are later exposed to the real virus.
The director of UK scientific research charity the Wellcome Trust, Jeremy Farrar, said there were often pauses in vaccine trials.
He told BBC radio in an interview that it demonstrated the importance of conducting vaccine trials properly, with independent oversight and the involvement of the regulator.
‘In the end the public must have absolute trust that these vaccines are safe and of course effective, and in the end will hopefully bring the pandemic to a close,’ he added.
The Government’s chief scientist, Sir Patrick Vallance, told a Downing Street press briefing yesterday that a vaccine may still be at least four months away.
‘Vaccines are progressing, some will read out this year in terms of efficacy and safety,’ he said. ‘I think there’s a reasonable chance that therefore we can think about the possibility of vaccination next year some time at larger levels.’
The Health Secretary also warned that the vaccine would not be available this year on Monday, stating: ‘The best-case scenario is that (the vaccine’s roll out) happens this year.
‘I think more likely is the early part of next year – in the first few months of next year is the most likely.’
After it completes clinical trials the vaccine will need to be approved by the regulator, the Medicine and Healthcare products Regulatory Agency, before it is made available to the public.
As many as 100 million doses have already been secured for the UK, Hancock said, while a further 300 million have been ordered by the US.
The roll out will see the vaccine supplied to countries at the same time and in equal amounts to ensure a fair distribution.
AstraZeneca has the capacity to produce close to three billion doses of the vaccine should this be required. Production has already begun, in anticipation of it receiving the go-ahead for use.
He denied claims a volunteer had suffered transverse myelitis, or swelling of the spinal cord
Transverse myelitis cases after a vaccination have been documented before, but concrete links between the condition and vaccinations have not been established, experts said.
The US-based Mayo Clinic concludes that the association so far is not strong enough to warrant limiting any vaccine.
A 2009 review in the journal Lupus of nearly 40 years of English-language publications found 37 cases of transverse myelitis associated with hepatitis B vaccines, measles-mumps-rubella, diphtheria-tetanus-pertussis and others.
The vaccines remained on the market, said Stephen Evans, a professor of pharmacoepidemiology at the London School of Hygiene and Tropical Medicine.
He added that it was extremely hard to link such autoimmune response to a single factor, saying it is ‘terribly difficult to be sure’.
RBC Capital Markets analyst Bryan Abrahams cautioned the trial participant’s condition must be thoroughly investigated.
‘Even a single case could possibly imply a rate or association higher in the study than what is normally observed sporadically’ he wrote to investors, adding a one in 10,000 risk, if confirmed, would likely be unacceptable.