AstraZeneca and the University of Oxford have admitted a manufacturing error that has led to questions over the initial results of the Covid-19 experimental vaccine. In a statement on Wednesday, the mistake is explained.
A few days earlier the company and the university said that the experimental vaccine is highly effective. But it did not mention why some participants in the study were not given the same amount of vaccine in the first of the two doses of the vaccine as expected.
Surprisingly, the group of people who volunteered to participate in the study were given lower doses of the vaccine, seem to be better protected than the group who were given the full dose.
AstraZeneca said the vaccine appeared to be up to 90 percent effective in the low-dose group, while the group that was given the full two doses showed the vaccine to be up to 62 percent. Overall, the drugmaker said the vaccine appears to be up to 70 percent effective.
But the way in which the results have been reached and the companies have given information, the experts have raised questions. Partial results were announced on Monday, which are part of a larger study going on in Britain and Brazil. The best vaccine dose will be found out in it. Simultaneously the safety and effectiveness of the vaccine will also be tested.