The UK is to assess how best to retain Covid-19 immunity over time after fully vaccinating almost a third of its population.
Britain’s government is launching a trial of seven vaccines to see which can generate a successful immune response as a booster dose for those who have received two shots.
This will help authorities to decide the most effective way to control the virus months after the country’s planned reopening on June 21.
“We will do everything we can to future-proof this country from pandemics and other threats to our health security,” Health Secretary Matt Hancock said.
Data from the trial will help to shape plans for Britain’s booster programme starting this year.
Volunteers may receive a different brand of vaccine for their booster than the one with which they were originally inoculated.
Those who received two doses developed by Pfizer and BioNTech, for instance, might receive a third from AstraZeneca or Valneva.
The other four vaccines being studied are from Moderna, Novavax, Johnson & Johnson and CureVac.
Those taking part will be given a booster at least 10 to 12 weeks after their second shot, and then be monitored for months after the trial to evaluate their immune response and any side-effects.
They may also be given a control shot or half-doses to assess how much is needed to maintain an immune response.
“We’re not expecting any of the vaccines to be detrimental,” said Prof Saul Faust of the University of Southampton, who is leading the trial.
“But some may have more problems with side-effects than others.”
The trial will include slightly fewer than 3,000 participants aged 30 and over, who will start receiving boosters in early June.
People in the UK who have had two vaccine doses can sign up for the trial from Wednesday evening.
It is being funded by the UK Vaccine Taskforce through the National Institute for Health Research.
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