Covid-19 vaccine: AstraZeneca will have to perform a new test, that’s why

CORONAVIRUS – The vaccine against the Covid-19 disease developed by the British laboratory AstraZeneca and the University of Oxford requires “an additional study,” the group’s director general said on Thursday, November 26 after the criticisms of reliability announced.

“Now that we’ve found what appears to be a better efficacy, we need to validate it, so we need to do more studies,” Pascal Soriot said in an interview with Bloomberg.

After Pfizer and Moderna, AstraZeneca was the third laboratory to release its vaccine, in collaboration with the British university. The laboratory announced an average efficiency rate of 70%, specifying that this result ranged from 90 to 62% efficiency, whether the patient received a full or half dose in the first injection.

Subsequently, the group’s general manager clarified this information: to everyone’s surprise, the results were more convincing on patients who received half a dose than in those who received a full dose. However, these results were criticized by the experts, who highlighted two problems in the methodology of the experiment.

Why an additional study?

First, the age of the participants who received a half dose (where the vaccine was most effective). As reported by the AP news agency, these volunteers were under the age of 55, which excludes “at-risk” groups over 60. The specialists therefore hypothesized that the excellent results obtained in this group could derive from this factor.

So they complained that the half dose injection was originally due to an error. As a result, only 3,000 patients followed this protocol, a number deemed insufficient to guarantee the reliability of the results. In a statement, the University of Oxford announced that it will resume half-dose trials on a larger scale. This is the whole purpose of the new study announced on Thursday.

Not necessarily late delivery

For the moment less compelling than Pfizer / BioNTech or Moderna, AstraZeneca’s vaccine has the advantage of using more traditional technology than these two competitors, which makes it less expensive and easier to store since ‘it can be stored in refrigerator and not at very low temperatures.

The results of this new international study “may be quicker” to come by, “because we know the effectiveness is high, so we need fewer patients,” he said. According to him, these procedures should not delay the approval of regulators in the European Union (which ordered 300 million doses in August) and the UK. However, the green light from the US authorities could take longer.

On Monday, AstraZeneca said it was rapidly advancing its planned production of 3 billion doses, which will be available in 2021. By comparison, Pfizer and its partner BioNTech have announced 1.3 billion doses by the end of 2021.

See also on The HuffPost: Covid: 90% effective vaccines, what it means … and above all not to say it