The British government says it may take part in a study that tries to deliberately infect volunteers who have been given an experimental vaccine against the coronavirus in an effort to more quickly determine if the vaccine works.
The approach, called a challenge study, is risky but proponents think it may produce results faster than typical studies, which wait to see if volunteers who have been given an experimental treatment or a dummy version get sick.
“We are working with partners to understand how we might collaborate on the potential development of a Covid-19 vaccine through human challenge studies,” the UK's Department for Business, Enterprise and Industrial Strategy said in a statement.
“These discussions are part of our work to research ways of treating, limiting and hopefully preventing the virus so we can end the pandemic sooner.”
Challenge studies are typically used to test vaccines against mild diseases to avoid exposing volunteers to a serious illness if the vaccine fails to work.
While coronavirus causes only mild or moderate symptoms in most people and seems to be especially mild in young, healthy people, the long-term effects of the disease are not well understood, and there have been reports of lingering problems in the heart and other organs even in those who do not feel sick.
In the US, the National Institute of Health (NIH) has downplayed the need for challenge studies given the speed with which vaccines are being developed, but said on Thursday it is taking some preliminary steps in case the more controversial approach eventually is required.
Those preliminary steps include examining the ethics of a challenge study, and funding research to create lab-grown virus strains that potentially could be used.
Tens of thousands of volunteers have already signed up around the world to test leading candidates and the coronavirus is still spreading widely enough in many locations that manufacturers are confident of answers by the end of the year.
In July, the NIH’s vaccine working group published a paper in The New England Journal of Medicine pointing out the risks of doing a challenge study with a virus that so far has no good treatment and is wildly unpredictable, occasionally killing even some young, otherwise healthy people.
“A single death or severe illness in an otherwise healthy volunteer would be unconscionable and would halt progress” toward a vaccine, the group warned.
The Financial Times newspaper says the move will be announced by the UK next week and will begin in January.
Dr Peter Horby, professor of emerging infectious diseases and global health at the University of Oxford, says he supports the idea.
The concept dates back to 1796, when scientist Edward Jenner found that exposing patients to cowpox disease protected them against future infections of smallpox, the first step in eradicating the deadly disease.
“It has real potential to advance science and get us to a better understanding of the disease and vaccines faster,” Dr Horby said.
On Thursday the UK recorded its highest ever number of daily new cases 6,634.
