A third dose of AstraZeneca Plc’s Covid-19 vaccine significantly boosted neutralizing antibody levels against Omicron, according to lab studies at the University of Oxford.
The vaccine, created by Astra and Oxford, saw neutralizing antibodies increase to similar levels as those after two doses against the Delta variant with a booster shot, the drug company said in a statement Thursday. A third dose produced higher levels of neutralizing antibodies than those found in individuals who had recovered naturally from the alpha, beta and Delta strains, the company said.
The results are largely good news for the vaccine, which has been sidelined in the West as a booster after messenger RNA vaccines were shown to be more effective in various trials. The study looked at 41 people who had been given a third dose.
Astra shares rose 0.3% in early London trading.
Data from another lab study showed individuals vaccinated with two doses of Astra’s shot retained neutralizing activity against Omicron, although a 36-fold decrease was observed from the original virus strain.
Omicron’s rapid spread and its ability to initially reduce antibody protection in many vaccines led many countries to launch accelerated booster campaigns. The U.K. alone reported more than 100,000 new Covid cases Wednesday for the first time, heaping pressure on Prime Minister Boris Johnson, who has resisted imposing further restrictions before Christmas.
