Astra-Zeneca Covid vaccine trial explanation

[jim mcnamara]

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

 

[Ygggdrasil]

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

 

[jim mcnamara]

@Ygggdrasil
thanks for the correction. :) See what you think of the statements in the video - it is not that long.

 

[Ygggdrasil]

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