This issue is, appropriately, contentious. As a vaccinologist - & citizen & relative of people in at-risk groups - I fully support the UK decision to increase dose intervals of both our Ox/AZ product and the Pfizer product. I'd happily receive either with a >8w gap. Here's why 🧵

For the Ox/AZ vaccine, it's fairly simple. The trial demonstrated efficacy at a range of dose intervals. Antibody responses after the boost were significantly stronger with longer intervals - see table 3.
https://t.co/10KPvahJ64
(so in response to @drmarkporter's point, higher immune responses with a longer interval is proven & now public. I haven't seen a similar analysis for efficacy against disease but the data exists and I suspect the regulators & JCVI committee have)
For Pfizer, there isn't direct evidence of efficacy with a >3wk interval. But as widely publicised, efficacy in the period from 14 days after first dose to 21 days is high.
Can we extrapolate from this to a longer interval? It's a judgment call. On one hand is evidence-based medicine's scepticism of anything not directly proven 'beyond reasonable doubt' in an RCT; on the other is a 'balance of probabilities' approach based upon the biology.
Based upon the biology, I'd eat my hat if the Pfizer vaccine is substantially less effective with a longer dose interval. Most vaccines induce stronger immune responses with longer intervals. A couple of examples below. There are more.
Regimes like the Ox/AZ use the same adenoviral vector to prime & boost so face 'anti-vector immunity' (immunity from the first dose to the viral 'postman' which must delivers the spike protein 'message' for the boost). This favours longer intervals specifically for Ad/Ad but...
...the above shows that longer intervals are better for regimes with different viral vectors, DNA priming, inactivated virus boosting - this isn't just an adeno effect. It's v rare for a 3wk interval to give stronger responses than 8+ wks (I can't think of examples, can you?)
Mechanistically, at 3w, the immune response to prime isn't complete- it hasn't yet produced all the memory B cells which give the best response to the boost. Once they are made, the memory cells last years! They won't forget how to respond to a boost in a few months.
I appreciate mechanistic arguments often prove to be wrong, and RCT evidence with Pfizer at longer intervals should definitely be produced ASAP... but as @zeynep has written in an excellent article today:
https://t.co/WrNVW5jRaW
There is a good debate:
@Bob_Wachter has written thoughtfully https://t.co/wZgvN937DV

@trishgreenhalgh @EricTopol @nataliexdean have all argued the other way from me - would welcome their thoughts on the above 🧵
I haven't yet seen a vaccine immunologist who has personally done experiments giving vaccines at different intervals and who is concerned about the longer interval... but I look forward to hearing that view too...

More from Government

This is a good piece on fissures within the GOP but I think it mischaracterizes the Trump presidency as “populist” & repeats a story about how conservatives & the GOP expelled the far-right in the mid-1960s that is actually far more complicated. /1

I don’t think the sharp opposition between “hard-edge populism” & “conservative orthodoxy” holds. Many of the Trump administration’s achievements were boilerplate conservatism. Its own website trumpets things like “massive deregulation,” tax cuts, etc. /2

https://t.co/N97v85Bb79


The claim that Buckley and “key GOP politicians banded together to marginalize anti-Communist extremism and conspiracy-mongering” of the JBS has been widely repeated lately but the history is more complicated. /3


This tweet by @ThePlumLineGS citing a paper by @sam_rosenfeld and @daschloz on the "porous" boundary between conservatives, the GOP and the far-right is relevant in this context.


This is a separate point but I find it interesting that Gaetz, like Roy Moore did In his failed Senate campaign, disses McConnell. What are their actual policy differences? MM supported taking health care away from millions, a tax cut for the rich, conservative judges, etc. /5

You May Also Like

Хајде да направимо мали осврт на случај Мика Алексић .

Алексић је жртва енглеске освете преко Оливере Иванчић .
Мика је одбио да снима филм о блаћењу Срба и мењању историје Срба , иза целокупног пројекта стоји дипломатски кор Британаца у Београду и Оливера Иванчић


Оливера Илинчић је иначе мајка једне од његових ученица .
Која је претила да ће се осветити .

Мика се налази у притвору због наводних оптужби глумице Милене Радуловић да ју је наводно силовао човек од 70 година , са три бајпаса и извађеном простатом пре пет година

Иста персона је и обезбедила финансије за филм преко Беча а филм је требао да се бави животом Десанке Максимовић .
А сетите се и ко је иницирао да се Десанка Максимовић избаци из уџбеника и школства у Србији .

И тако уместо романсиране верзије Десанке Максимовић утицај Британаца

У Србији стави на пиједестал и да се Британци у Србији позитивно афирмишу како би се на тај начин усмерила будућност али и мењао ток историје .
Зато Мика са гнушањем и поносно одбија да снима такав филм тада и почиње хајка и претње која потиче из британских дипломатских кругова

Најгоре од свега што је то Мика Алексић изговорио у присуству високих дипломатских представника , а одговор је био да се све неће на томе завршити и да ће га то скупо коштати .
Нашта им је Мика рекао да је он свој живот проживео и да могу да му раде шта хоће и силно их извређао