AstraZeneca and Oxford University have recently encountered a manufacturing error of their experimental COVID-19 vaccine, giving rise to questions about the preliminary trial results.

The manufacturing error was revealed following the announcement about the high effectiveness of their vaccine among participants. Moreover, the pharmaceutical company & the university failed to mention the reason why the candidates did not receive as much vaccine in 1^st of the 2 shots.

Unexpectedly, the group of volunteers who received a lower dose seemed to be more immunized than the volunteers who obtained 2 full doses. For the record, the vaccine showed 90% effectiveness among the low-dose group and only 62% effectiveness in the group that received 2 full doses. In combination, the drug makers revealed that the vaccine candidate appeared to be 70% effective.

Prior to conducting the research, scientists provide steps they are taking as well as the process of analyzing the results. A deviation from this protocol can put the trial results in question.

As per the statement made by Oxford University, a few vials adopted in the clinical trial did not have the right vaccine concentration, due to which some volunteers received only half the dose. Additionally, the university has cited that it had discussions about the issue with the regulators and agreed to complete its last stage of the study with the two groups.

It has also been revealed that none of the volunteers in the low-dose group were from the age group of over 55 years. Therefore, the high effectiveness of the vaccine in this group might be possible due to the fact that younger people tend to have a stronger immune response as compared to older people.

Details about the trial results will be published in the medical journals and shared with the UK regulators to decide on the authorization of its distribution. These reports will include demographic information of people in each group and the effectiveness of the vaccine.

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https://www.chicagotribune.com/coronavirus/ct-nw-astrazeneca-vaccine-study-results-20201125-pjhbl4k27zasxnrkygfwde2nzq-story.html