The United Kingdom will hold a new trial to see whether or not using two different COVID-19 vaccines still works in preventing the novel coronavirus, according to CNBC.

  • The trial would use different COVID-19 vaccines for the first and second dose to see if they still are effective in preventing the coronavirus, CNBC reports.
  • So one version of the vaccine — say Pfizer’s version — would be used for the first dose. Another version — like Moderna’s — would be used for the second “booster” shot.
  • For this study, participants will get the AstraZeneca vaccine first followed by a shot from Pfizer for the second dose, per The Associated Press.
  • This would allow the United Kingdom to be more flexible in how it distributes the vaccines to its people.
  • The University of Oxford will lead the trial, which will be run by the National Immunisation Schedule Evaluation Consortium, according to CNBC.
Related
Pfizer-BioNTech vaccine can defeat the COVID-19 variant found in the UK

Key quote

  • “If we do show that these vaccines can be used interchangeably in the same schedule this will greatly increase the flexibility of vaccine delivery, and could provide clues as to how to increase the breadth of protection against new virus strains,” said Matthew Snape, chief investigator and associate professor in pediatrics and vaccinology at the University of Oxford, according to CNN.
Related
U.K. becomes first country in the world to approve Pfizer coronavirus vaccine
Will the COVID-19 vaccine stop the UK coronavirus variant?

Is it safe and legal?

Per The Associated Press, the U.K. and U.S. both have guidelines that say the vaccines aren’t interchangeable. However, the two vaccines can be mixed if the version used for the first dose isn’t available for the second dose, or if health officials are unsure which vaccine was used for the first dose.