Coronavirus vaccine: Two doses of Oxford / AstraZeneca vaccine provoke a good immune response World News

LONDON: Oxford University’s Covid-19 vaccine candidate has a better immune response when using a two-dose, rather than a full-dose regimen, followed by a half-dose booster, the university said on Thursday, citing data from early studies.
The developers of the vaccine candidate, which was licensed by the pharmaceutical company AstraZeneca, have already published the results of studies in the next stage that show greater efficacy when half a dose is followed by a full dose compared to a two-dose regimen. However, more needs to be done to affirm this result.
The latest details from the Phase I and 2 clinical trials published on Thursday made no reference to the half-dose / full-dose regimen, which Oxford said was “unplanned” but approved by regulators.
Once seen as a leader in the development of a coronavirus vaccine, the British team was overtaken by the American doctor Pfizer, whose shots were launched in Great Britain and the United States this month.
Earlier data from the latest Phase 3 studies showed that the efficacy was 62% for study participants given two full doses, but 90% more robust for a smaller subgroup given first half, then a full dose.
In its statement Thursday, the university said it had explored two dosing regimens in early-stage studies, a full-dose / full-dose regimen and a full-dose / half-dose regimen, investigated as a possible dose”.
“It is shown that booster doses of the vaccine induce stronger antibody responses than a single dose, with the standard dose / standard dose inducing the best response,” the university said in a statement.
The vaccine stimulates the broad functions of antibodies and T cells, he said.