Mix-and-match doses boosts immune response to AZ: study

In a Lancet preprint paper, Oxford University researchers say an AstraZeneca dose followed by Pfizer produced the best T-cell responses
Reuters Health

A mixed schedule of COVID-19 vaccines where a dose of Pfizer is given four weeks after an AstraZeneca dose will produce better immune responses than giving another dose of AstraZeneca, say UK researchers.

The pre-print study, called Com-COV, compared mixed two-dose schedules of Pfizer and AstraZeneca vaccines, and found that in any combination, they produced high concentrations of antibodies against the coronavirus spike protein.