Doubts surface over Oxford vaccine efficacy claims

An additional trial is being launched to clarify the optimum dosage for the viral vector vaccine

An additional, global trial of the Oxford COVID-19 vaccine will be conducted to quell doubts over the 90% efficacy interim finding reported in phase three trial results earlier this week, AstraZeneca says.

The company’s CEO, Pascal Soriot, says a new study will evaluate whether a half-dose regimen, which was mistakenly given to more than 2700 trial participants, outperforms two full doses of the vaccine across all ages and ethnicities.