Friday November 27, 2020
How effective is Astrazeneca’s corona vaccine really? Previous study data promise 70 percent protection. But the methodology behind calculating this value raises questions. This now means that the British government needs to act.
The vaccine results from the pharmaceutical company Astrazeneca are being reviewed on behalf of the UK government. This is a “first important step in the approval of the vaccine if it meets the safety, efficacy and quality standards,” said the Ministry of Health in London. The test is to be carried out by the UK Medicines Regulatory Authority.
Previously, there were doubts about the design of the clinical trials and the high effectiveness of the vaccine. The Swedish-British group is therefore planning additional investigations. A spokeswoman for Astrazeneca in London announced that they should “supplement the data from existing studies,” without giving details.
According to the study data so far, the vaccine developed with the University of Oxford is said to offer an average of 70 percent protection against Covid-19. According to the group, the effectiveness could possibly be significantly higher with a special dosage. Data from a combined phase II / III study were taken into account, in which the test subjects first received half a dose of the vaccine and a month later another full dose. According to the information, the effectiveness here was 90 percent. On the other hand, the results of a phase III study were taken into account, in which test subjects received two full doses. The effectiveness calculated so far was 62 percent.
Taken together, according to the group, the effectiveness is 70 percent. Critics criticized the effectiveness calculations in this way, since different doses had been given. US researchers also complained that in the study, which led to a high vaccination success of 90 percent, no participant was older than 55 years. However, senior citizens are considered to be a particularly vulnerable group. A big advantage of the vaccine: According to the information it can be stored at refrigerator temperatures of two to eight degrees.
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“We have formally asked regulators to evaluate the vaccine (…), understand the data and determine whether it meets strict safety standards,” said Health Secretary Matt Hancock. “We are working tirelessly to be in the best possible position to deliver a vaccine once it is approved by the independent regulatory agency MHRA.”
Unlike the promising vaccines from the Mainz company Biontech and the pharmaceutical company Pfizer as well as the US company Moderna, the British-Swedish preparation does not belong to the mRNA vaccines. According to preliminary data, the effectiveness of the vaccines from Pfizer / Biontech and Moderna is around 95 percent for double vaccinations.
The active ingredient AZD1222 used by Astrazeneca is based on the weakened version of a cold virus from chimpanzees. It contains genetic material from a surface protein with which the Sars-CoV-2 pathogen docks onto human cells. The agent is said to promote the formation of specific antibodies as well as T cells – both are important for the immune system. In total, countries around the world have already ordered billions of cans from Astrazeneca.