@pcmac41 @PaoloWalnuts I looked into this as I was very surprised and thought it could be quite dangerous to go against the trial design.

I learnt a lot while i was doing it! There are a lot of misunderstandings and quite a few counterintuitive bits as well.

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@PaoloWalnuts There's some obvious stuff like the fact that the JCVI is a longstanding body with a lot of very bright folks on it. Also, again stating the obvious, immunology and immune responses are really complex.

I've worked on a mAb and i will happily admit i didn't get the details! 1/

@PaoloWalnuts To digress a little, i think AZ have serendipitously learnt lots about adenovirus vaccines through the seeming unplanned hiccups in their study. This is all brand new tech and it wasn't entirely obvious beforehand that small initial dose and long interval would be good. 2/

@PaoloWalnuts It makes sense afterwards (for an adenovirus vx) and it also confirms why longer time between doses can be good. You let the vx get all the way through "teaching the body how to respond a little bit, and once it's developed its response it's way more efficient with the booster 3/

@PaoloWalnuts Which begs a critical question that really bothered me: why did pfizer go with a 21dy regime? We have to trust what they say don't we? 4/