AstraZeneca-Oxford’s COVID-19 vaccine up to 90% effective, no adverse health effects reported


Interim data analysis of the phase-3 trial of AstraZeneca-Oxford’s ChAdOx1 nCoV-2019 vaccine offers high efficiency in preventing COVID-19 disease, according to an Oxford University press release.

The results are based on 131 COVID-19 cases seen in the phase-3 trial. Two doses of the vaccine given in two different regimens showed different efficacies. In the case of the regimen where a halved dose was used as a prime followed by a standard dose of a booster, the efficacy was 90%. However, where full doses were used both prime and booster doses, the efficacy was only 62%. The combined analysis from both dosing regimens resulted in an average efficacy of 70%.

Like Pfizer-BioNTech and Moderna’s vaccine, Oxford’s vaccine also shows that it’s capable of preventing severe COVID-19 cases. No hospitalized or severe cases were seen in anyone who received the Oxford’s vaccine, the release says. Unlike Pfizer’s vaccine that requires -70 to -80°C ultra-cold storage, the Oxford vaccine can be stored at 2 to 8°C, which makes it easier for its distribution and storage. In addition, Pfizer-BioNTech and Moderna use mRNA technology for their vaccine which triggers killer and memory Lymphocytes. Oxford’s vaccine – ChAdOx1 nCoV-19 – is made from “adenovirus” which causes the common cold. It has been genetically modified and weakened so that it is impossible for it to grow in humans further.

The interim analysis was carried out on data collected as of November 4, when the trial had reached the predetermined target for the first interim analysis. The trial had enrolled over 24,000 participants from diverse racial and geographical groups in the U.K., Brazil, and South Africa. Due to the easy storage capability and low-cost vaccine of Oxford, many developing countries may benefit.

Unlike Pfizer’s vaccine which is expected to cost nearly $37, Oxford’s vaccine is expected to cost $13. “A key element of Oxford’s partnership with AstraZeneca is the joint commitment to provide the vaccine on a not-for-profit basis for the duration of the pandemic across the world, and in perpetuity to low and middle-income countries,” the release says.



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