Scientists at the University of Oxford say they should have at least a million doses of a coronavirus vaccine by September this year.
The UK government, which is backing the project, said there were “no guarantees” and it was not possible to put a date on a vaccine.
The first patients are expected to take part in the Oxford trials next week.
However, it is still too soon to know whether it will be either safe or effective.
Most experts still estimate it will take 12 to 18 months to develop and manufacture a vaccine.
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