A new trial has been announced that will look at whether a booster vaccine will protect against new variants.
All seven vaccines the UK has ordered will be tested on working-age people and over-75s as part of a randomised trial.
The findings will help vaccine advisers decide if re-vaccinating some people in the autumn is necessary.
The study, which costs £19.3 million, is being funded by the government and led by the University Hospital Southampton NHS Foundation Trust.
Speaking at Downing Street, the Health Secretary, Matt Hancock, said the trial would help to ensure “vaccines stay ahead of the virus.”