Oxford University study finds mixing a first dose of the Pfizer or Astrazeneca vaccine with a second Moderna shot yields higher antibodies.

A major British study into mixing COVID-19 vaccines has found that people had a better immune response when they received a first dose of AstraZeneca or Pfizer-BioNTech shots followed by Moderna nine weeks later, according to the results.

If the AstraZeneca-Oxford vaccine is followed by a Moderna or Novavax shot, higher antibodies and T-cell responses were induced versus two doses of AstraZeneca-Oxford, according to researchers at the University of Oxford.

The study of 1,070 volunteers also found that a dose of the Pfizer-BioNTech vaccine followed by a Moderna shot was better than two doses of Pfizer-BioNTech.

The study also found that a first dose of the AstraZeneca-Oxford vaccine followed by any of the other candidates in the study generated a particularly robust response, consistent with findings in June.