Thread by @latikambourke

MORE good news!!!
AstraZeneca/Oxford vaccine is 70 per cent effective after first does and COULD be 90 per cent effective after second. And....it has a fridge temperature. ox.ac.uk/news/2020-11-2…

PM Boris Johnson: "Incredibly exciting news the Oxford vaccine has proved so effective in trials. There are still further safety checks ahead, but these are fantastic results."

https://twitter.com/BorisJohnson/status/1330779374988259328

Australia has an agreement to buy 3.8 million doses and produce 30 million locally, vaccinating 16.9 million people...But with less certainty about AstraZeneca's efficacy rate will people want Pzifer or Moderna's if they can get it/choose.

https://twitter.com/latikambourke/status/1328312858896175105?s=20

obvs typo 'dose*' apolz.

Professor Andrew Pollard, Chief investigator with the Oxford Vaccine Group on BBC: "70 per cent it better than the flu vaccine is in most years."

Prof Pollard says 70% comes after 2 FULL doses while the 90% result came after administering a HALF dose initially and then full dose for the second. He says this is 'intriguing' because it means potentially more vaccines available. 'We have to dig into [that] now.'

Prof Pollard: "We're not making comparisons [with Moderna/Pfizer]." "We are going to need all the vaccines, it's not a question of which one to take, I'd be personally happy to take any of these vaccines tomorrow."

Prof Pollard says the refrigeration temps for Oxford/AstraZeneca vaccine plus that its not-for-profit are two advantages, as it means it's affordable and easily distributable.

Briefing from the Oxford Vaccine Group/AstraZeneca now underway.

Prof Louise Richardson says they chose to partner commercially with @AstraZeneca because they didn't want their vaccine to be one for the wealthy countries or for it to be a profit exercise.

Prof Sarah Gilbert: Previous work developing a vaccine for MERS turned out to be relevant - we'd already made a vaccine and conducted a human trial with a coronavirus.

Prof Andrew Pollard: 'We've got a vaccine for the world.'
'Although the headline is 70 per cent protection we do have a sub-group where we saw 90 per cent protection'. (they took half dose FIRST and then full dose)

Prof Andrew Pollard: 'this is an incredibly exciting moment for human health.'

Pascal Soriot from @AstraZeneca: Importantly no severe cases were seen and there were no hospitalisations so it really is an effective vaccine.

Pascal Soriot says the half-dose option (which had 90 per cent efficacy) means they can vaccinate more people than previously thought.

Mene Pangalos from @AstraZeneca 'I have little doubt that this vaccine is going to have a big impact globally ... in terms of getting the pandemic under control.'

Questions - why does the half dose first produce the 90 per cent result?

Prof Pollard: We think that by giving a smaller first dose that we're priming the immune system differently, we're setting it up better to respond. What we don't know is whether that's the quality or quant.

Prof Gilbert answering how much the vaccine reduced transmission.

'We are seeing a difference partic with low dose candidate group, we're seeing a reduction ... but it looks like this vaccine is working against severe disease.'

Interesting response - no numbers given.

But Prof Glibert says it's good news all round because we are seeing a difference on transmission.

Prof Gilbert says the half dose producing better result may be the result of the dose behaving or more closely mimicking the actual virus.

Prof Pollard says the technique of priming the immune system (the half dose method) is known 'so it's not a total surprise'.
He says this is commonly seen when vaccinating babies. But he says what is different is seeing the result in adults. 'It is intriguing'.

Interesting - On 90% success rates of US rivals Moderna and Pfizer, Prof Pollard says comparisons may not be right to conduct rn because what is being measured is still unknown and not revealed in the press releases.

Prof Pollard: "in the end what we need to be able to do to get back to normal is to have people around the world vaccinated to stop them going into hospital and we need all of the vaccines in order to do that b/c we don't have enough supply for the whole of the planet."

Prof Sarah Gilbert says the first announcement of a vaccine a few weeks ago changed the world because it showed a coronavirus could be done.

This was in response to a question inviting her to put in a nutshell how important their announcement is.

Answer v. much Team Humanity

Pascal Soriot from @AstraZeneca applauding success of multiple vaccine candidates says the three vaccines announced still fall short of supplying the world: 'There's no competition really.'

I asked about whether the storage fridge temps was happy accident or deliberately designed this way - Prof Sarah Gilbert says this was already one of the 'plus points' from previous work on vaccines. 'You have to think about all the other characteristics as well.'

And also asked whether any indiciations of how long protection from vaccine might last, Prof Pollard 'it's something we're going to have to be looking out for ... at this moment there's no evidence of that [being like the flu jab b/c virus mutates each year].'

Prof Pollard: "We've got a little bit of optimism based on some of the previous studies with this type of vaccine that we might have immune responses that last at least a year. But all of this has to be studied, it's not something we have answers to at the moment." BRIEFING ENDS