[magnus]

One other thing about the "half dose" theory... it was an accident.  As in, the company didn't mean to have an arm with a half-dose initial dose.

https://www.fiercebiotech.com/biotech/as...e-efficacy

Pangalos said the mistake became apparent when researchers noticed the side effects seen in some participants were milder than expected. An attempt to explain the mild side effects revealed “they had underpredicted the dose of the vaccine by half,” Pangalos said. The participants went on to take a full booster shot.

Because this was not a pre-specified analysis, it is correct for the company to lump in the 90% with the 62% efficacy of the full-dose.  In normal times, the FDA would ask the company to run a new trial with the half-dose first dose before it could make any claims about the 90% efficacy of a half-dose initial dose, because, as you mention it, because the 90% efficacy could have arisen by chance.  These are not normal times, though, and it is possible that they will allow the regimen with some post-marketing commitments to report on its efficacy.

BC

One of the more vocal scientific voices during this pandemic, Natalie Dean, is worried about the transparency and rigor of the AstroZen trials.  

[tweet] https://twitter.com/nataliexdean/status/...70400?s=20[/tweet]

She goes on to say that the protocols for this study seem to vary per country that the study is conducted in and she worries that the sample size is indeed too small to commit on.  She's not coming down against the vaccine. Just the methods with which this vaccine is being advanced.

[magnus]

One other thing about the "half dose" theory... it was an accident.  As in, the company didn't mean to have an arm with a half-dose initial dose.

https://www.fiercebiotech.com/biotech/as...e-efficacy

Pangalos said the mistake became apparent when researchers noticed the side effects seen in some participants were milder than expected. An attempt to explain the mild side effects revealed “they had underpredicted the dose of the vaccine by half,” Pangalos said. The participants went on to take a full booster shot.

Because this was not a pre-specified analysis, it is correct for the company to lump in the 90% with the 62% efficacy of the full-dose.  In normal times, the FDA would ask the company to run a new trial with the half-dose first dose before it could make any claims about the 90% efficacy of a half-dose initial dose, because, as you mention it, because the 90% efficacy could have arisen by chance.  These are not normal times, though, and it is possible that they will allow the regimen with some post-marketing commitments to report on its efficacy.

BC

One of the more vocal scientific voices during this pandemic, Natalie Dean, is worried about the transparency and rigor of the AstroZen trials.  

[tweet] https://twitter.com/nataliexdean/status/...70400?s=20[/tweet]

She goes on to say that the protocols for this study seem to vary per country that the study is conducted in and she worries that the sample size is indeed too small to commit on.  She's not coming down against the vaccine. Just the methods with which this vaccine is being advanced.