Skip to main content
Premium Trial:

Request an Annual Quote

One, Then the Other

University of Oxford researchers are investigating whether mixing different COVID-19 vaccines provides the same or better protection than one type of vaccine alone, Business Insider reports.

With £7 million (US $9.5 million) in UK government funding, the researchers are conducting a trial of 820 people over the age of 50 who have yet to receive a COVID-19 vaccine, the Guardian adds. For their first dose, volunteers will receive either the AstraZeneca-Oxford University or the Pfizer-BioNTech vaccine. Then, for their second dose, some volunteers will receive the same vaccine they were previously given and others will receive the other.

When the UK floated this idea in December, Kate Bingham, outgoing chair of the UK's vaccine taskforce, told the Guardian the concept is known as a heterologous prime-boost. "It means mix and matching vaccines," she added.

The trial will also examine different timing — 28 days and 12 weeks — between vaccine doses.

"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," Oxford's Matthew Snape, the study's chief investigator, says in a statement.