Astra-Zeneca Covid vaccine trial explanation

In summary: The ChAdOx1 nCoV-19 vaccine (AZD1222) has demonstrated moderate efficacy against SARS-CoV-2. The interim analysis of four randomized controlled trials in Brazil, South Africa, and the UK found that the vaccine reduced the incidence of SARS-CoV-2 illness by 64% and 90%, respectively. However, more work is needed to confirm the vaccine's efficacy and safety.
  • #1
jim mcnamara
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Links for some of the science are included - this presentation is based on press releases. The peer reviewed data will be available shortly.



Some things to note - results show both 64% and 90% effective,the video explains this one
The tests looked for positive Covid tests in volunteers, not simply symptoms. This is different from Moderna, for example.

There are two aspects of vaccination -
1. reducing/preventing infection
2. reducing/preventing symptoms
 
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  • #2
jim mcnamara said:
The tests looked for positive Covid tests in volunteers, not simply symptoms.

While the trial involved frequent RT-qPCR testing of trial participants to detect asymptomatic COVID-19 cases, the published trial protocols specify that the primary endpoint of the trial is symptomatic COVID-19 illness, and the AstraZeneca press release is reporting efficacy based on the primary endpoint.

The actual data released in the press release appear to be somewhat of a mess, combining data from two separate studies, so it's hard to evaluate their claims without a more full reporting of the data:
The problems start with the fact that Monday’s announcement did not present results from a single, large-scale, Phase 3 clinical trial, as was the case for earlier bulletins about the BNT-Pfizer and Moderna vaccines. Instead, Oxford-AstraZeneca’s data came out of two separate studies: one in the UK that began in May, and another in Brazil, which got started at the end of June. These two studies were substantially different from one another: They didn’t have standardized dosing schemes across the trials, for one thing, nor did they provide the same “control” injections to volunteers who were not getting the experimental Covid vaccine. The fact that they may have had to combine data from two trials in order to get a strong enough result raises the first red flag.
https://www.wired.com/story/the-astrazeneca-covid-vaccine-data-isnt-up-to-snuff/

See my post here for more discussion: https://www.physicsforums.com/threads/coronovirus-vaccine-progress.992484/post-6421572
 
  • #3
@Ygggdrasil
thanks for the correction. :) See what you think of the statements in the video - it is not that long.
 
  • #4
The Oxford-AstraZeneca team has published the interim analysis of their Phase II/III trial in the peer-reviewed medical journal, The Lancet:

Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)32661-1/fulltext

Commentary from The Lancet: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)32623-4/fulltext
Popular press coverage:
https://www.statnews.com/2020/12/08...vid-19-vaccine-show-it-has-moderate-efficacy/
https://blogs.sciencemag.org/pipeli.../the-oxford-astrazeneca-vaccine-efficacy-data
 

Related to Astra-Zeneca Covid vaccine trial explanation

What is the Astra-Zeneca Covid vaccine trial?

The Astra-Zeneca Covid vaccine trial is a clinical trial conducted by the pharmaceutical company Astra-Zeneca to test the safety and effectiveness of their Covid-19 vaccine candidate. The trial involves giving the vaccine to a large number of participants and closely monitoring their health and immune response.

How is the Astra-Zeneca Covid vaccine being tested?

The Astra-Zeneca Covid vaccine is being tested through a series of clinical trials that follow strict scientific protocols. These trials involve giving the vaccine to different groups of people and comparing their outcomes to those who did not receive the vaccine. The trials also involve collecting and analyzing data on the participants' health and immune response.

What are the results of the Astra-Zeneca Covid vaccine trial?

The results of the Astra-Zeneca Covid vaccine trial have shown that the vaccine is safe and effective at preventing Covid-19. It has been found to have an efficacy rate of around 70% in protecting against the virus. However, further data is still being collected and analyzed to ensure the accuracy of these results.

How does the Astra-Zeneca Covid vaccine work?

The Astra-Zeneca Covid vaccine works by using a weakened version of a common cold virus (adenovirus) that has been modified to carry genetic material from the Covid-19 virus. This genetic material then triggers an immune response in the body, producing antibodies and T-cells that can recognize and fight off the actual Covid-19 virus if a person is exposed to it.

When will the Astra-Zeneca Covid vaccine be available for public use?

The Astra-Zeneca Covid vaccine has been approved for emergency use in several countries and is currently being rolled out for public use. The exact availability of the vaccine may vary depending on the country and its distribution plans. It is expected that the vaccine will be widely available to the public in the coming months.

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