AstraZeneca plans new Oxford vaccine trial to prove jab works on all ages
More volunteers will be recruited to test half-dose regimen as critics question latest results
A fresh global trial of the Oxford Covid-19 vaccine is being launched to clarify how effectively the jab protects older age groups - and banish doubts that have emerged since preliminary results were published on Monday.
“The company wants the new test to confirm the 90% efficacy rate that the shot showed in a portion of an existing trial,” Bloomberg reports.
That impressive rate was the result of an error, when a sub-group of about 2,700 trial subjects were given a half dose of the vaccine followed by a full booster dose, instead of the two full doses received by other participants.
People in the sub-group were found to be the least likely to fall ill with Covid - but were all under the age of 55, and therefore less vulnerable to the coronavirus, health officials have revealed.
In the US, however, questions have been asked about whether AstraZeneca’s interim data tells the whole story.
“The problems start with the fact that Monday’s announcement did not present results from a single, large-scale, Phase 3 clinical trial,” says Wired. Instead, it included results from two separate trials, one in the UK and one in Brazil, which makes it hard to be sure researchers haven’t “cherry-picked the data”, the magazine adds.
AstraZeneca has pledged to publish its full results in a peer-reviewed journal as soon as possible.
Despite the urgency created by the mounting Covid-19 death toll, many experts have “called for patience”, Politico reports. Most believe that the full data will confirm the effectiveness of the Oxford vaccine.
And while some questions must still be answered, the recent vaccine trial results are “very good news”, says Professor Peter Openshaw of Imperial College London.
He told the BBC: “It is remarkable that each of the trials that are now reporting shows protection, which we did not know was going to be possible.”