Oxford said on Thursday that its COVID-19 vaccine candidate has a better immune response when using a two full-dose regime rather than a full-dose followed by a half-dose booster.
The vaccine candidate, which has been licensed to AstraZeneca, has published preliminary results from late-stage studies showing greater efficacy when a half dose is followed by a full dose, compared to a two full-dose regime. However, more work is needed to affirm the result.
The Phase I/II clinical trials details were released on Thursday and they did not contain any reference to the half/full dose regime, which Oxford said was not planned but approved by regulators.
Oxford said it had studied two dosing regimes in early stage trials, a full-dose/full-dose regime and a full-dose/half-dose regime, which were being investigated as a possible “dose-sparing” strategy.
“The booster doses of the vaccine are both shown to induce stronger antibody responses than a single dose, the standard dose/standard dose inducing the best response,” the university said in a statement.
The vaccine “stimulates broad antibody and T cell functions,” it said after publishing further data from the Phase I/II clinical trials.