Newly published data shows 90% efficacy only in small group who got half-dose first
The Oxford AstraZeneca Covid vaccine has efficacy of 90% in a small group who got a half-dose first, but only 62% in the majority, full trial data newly published in the Lancet has confirmed.
The results may create a quandary for regulatory bodies, which will have to decide on how the vaccine should be used if they approve it.
