We’ve seen headlines this week about a possible vaccine that protects against the coronavirus becoming available within six months.
Several news outlets have run the story, based on expert evidence given to the House of Commons Science and Technology by Andrew Pollard, Professor of Paediatric Infection and Immunity at Oxford University.
You may also have seen the news that the first UK research team, also based at Oxford, is looking for volunteers to take part in trials of a possible vaccine.
But how long will it be before a working vaccine is widely available?
Professor Pollard told MPs: “I believe that six months is possible, but it needs a lot of things to fall in place in order for that to happen… there’s lots of reasons why it may be more difficult to get there in that time period.”
Other experts are more cautious about the timescale, and there are good reasons to think the process might take longer than the most optimistic forecasts.
How is the search for a vaccine going?
There are at least 44 candidates for a possible vaccine in various stages of development around the world, according to the World Health Organization.
Researchers in China and the US have already begun Phase 1 clinical trials. This means they are testing the vaccine on human volunteers to try to establish that it is safe and that it provokes a response from the immune system.
Many researchers are pioneering new kinds of vaccine design, and if a new coronavirus vaccine emerges, it may be the first of its kind to be used globally.
In the UK, scientists at Oxford University say they will begin testing a candidate vaccine on people within weeks.
They are using an adenovirus vaccine vector – a way of generating an immune response without giving people a form of the virus itself.
The basic structure has been studied extensively already, which has helped to cut development time, but vaccines made in this way are not widely used.
How long does it take to develop a vaccine normally?
Several years. Finding a candidate usually takes a lot of work in the laboratory, then what is called “pre-clinical” work, which sometimes involves testing on animals.
There are three phases of trials involving human subjects. Phase 1 trials tend to be quite small and the emphasis is on safety.
Phases 2 and 3 expand the number of test subjects. Scientists are looking for evidence that the trial vaccine is safe and effective against the target disease, as well as checking for possible side effects.
After the clinical trials are finished, regulatory bodies step in. In the UK the regulator is the Medicines and Healthcare products Regulatory Agency. It’s the MHRA’s job to look at all the data from the trials and approve the new vaccine for use if they believe it is safe and effective.
After sign-off from regulators, manufacturers need to actually produce the vaccine in sufficient quantities.
All of these different stages – clinical trials, regulation, manufacturing – can take years in normal conditions.
Can the process be accelerated?
Some bits of the development timeline can be speeded up. For example, regulators might drop everything else and divert all their resources towards a coronavirus vaccine in order to get to an approval decision quicker.
And manufacturers might begin to prepare to make large quantities of a certain drug before it is signed off – although this comes with considerable commercial risk for drug companies.
But there are other stages that cannot be rushed, for safety reasons. In the clinical trials, scientists are looking to see how volunteers respond to the vaccine and whether they develop side-effects. This obviously takes time.
The Oxford Vaccine Centre say they are beginning “vaccine manufacturing scale-up immediately” so that the vaccine can be available for NHS workers and vulnerable people immediately if the trials are successful.
But the Oxford researchers are also telling potential volunteers that the first trial alone will take six months, and that there is still work to be done before the trial begins.
Dr Doug Brown, Chief Executive of the British Society for Immunology, said: “This trial is without doubt a huge step forwards in our attempts to find a vaccine against SARS-CoV-2, but we should remember that we can only speed up the research effort by so much.
“This vaccine candidate still needs to go through many stages of testing to ensure that it is both safe and effective for wide-scale use. We need to be realistic about the timescale in which this can take place.”
Professor Adam Finn, Professor of Paediatrics at the University of Bristol, told FactCheck: “You can cut the bureaucracy and you can cut the red tape. You can put a lot of people on to it. You can even speed up the manufacturing. But in the end, there are things that will take a certain amount of time.”
Prof Finn also cautioned against assuming that even one successful vaccine will emerge from the dozens of potential candidates, pointing out that we still don’t have a vaccine for HIV after decades of research.
“It’s a bit like a horse race. It’s like setting off 35 horses in the Grand National, of which 32 are going to fall, and one or two or three are going to make it to the finishing line.
“There is the possibility that we are all sitting here a year from now and we still haven’t cracked it. I think we have just got to bear in mind that there are no certainties here.”