AstraZeneca says its vaccine needs ‘additional study’
The head of British drug manufacturer AstraZeneca said on Thursday further research was needed on its Covid-19 vaccine after questions emerged over the protection it offers, but the additional testing is unlikely to affect regulatory approval in Europe. AstraZeneca and its partner, the University of Oxford, announced on Monday that it was seeking regulatory approval for the vaccine after it showed an average 70-percent effectiveness.
That rate jumped to 90 percent when an initial half-dose then a full dose was given, similar to that in rival vaccines in development by Pfizer/BioNTech and Moderna. But US scientists have said the higher rate of effectiveness came during tests in people aged 55 and under, and was discovered by accident during the clinical trials.
