Oxford’s Covid-19 vaccine has a better immune response when a two full-dose regime is used rather than a full-dose followed by a half-dose booster, the university said on Thursday. The details from the Phase I/II clinical trials released on Thursday made no reference to the half-dose/full-dose regime, which Oxford has said had been “unplanned” but approved by regulators, Reuters has reported. The vaccine “stimulates broad antibody and T cell functions,” it said after publishing further data from the Phase I/II clinical trials.