Source please?
I’m wondering how they have sufficient data as they’d have to measure COVID cases before the second dose and would like to know what the infection rate there is.
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I’m wondering how they have sufficient data as they’d have to measure COVID cases before the second dose and would like to know what the infection rate there is.
The advice will be to give as many people a possible their first dose as soon as possible - but not to rush to give the second dose at 4 weeks. They're still recommending a second booster dose but suggesting a delay of up to 12 weeks is ok.
That's actually consistent with the AZ report that a second dose at 8-12 weeks gives the best efficacy results.
Crucially it's being reported that a single dose will rapidly give people some immunity, and will reduce the number becoming seriously ill.
https://www.bbc.co.uk/news/health-55280671
That's actually consistent with the AZ report that a second dose at 8-12 weeks gives the best efficacy results.
Crucially it's being reported that a single dose will rapidly give people some immunity, and will reduce the number becoming seriously ill.
https://www.bbc.co.uk/news/health-55280671
It’d be nice to see the source data..
I think thats sound. Vaccinate as many people as possible and a lot of time to close the loop with the booster
wonder what the efficacy percentage is with the first dose (or rather first half-dose), as long as it prevents severe covid clinically across the age groups I’m more than happy with that
Do we know if the regime is a full dose or a half dose 1st?
AZ CEO says they can supply 2m doses a week to the UK no problem. Challenge will getting them rolled out. Should be a lot easier than the other vaccines though. Hancock refused to commit to a weekly number.
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Full dose I believe.
I'm hoping we'll see more detailed results that are acting as the basis for the advice from AZ or the MHRA today.
Based on article approval seems for 2 full doses.
Surely they havent been testing for 7-8 months to suggest 2 shots 3 months apart results in a long term immune response..
if their best set of results is from getting 2 full doses 3 months apart, are they saying a shot triggers an immune response that lasts about 3 months and you have to get another full shot after 3 months?
if their best set of results is from getting 2 full doses 3 months apart, are they saying a shot triggers an immune response that lasts about 3 months and you have to get another full shot after 3 months?
Based on the information in the publication, the time interval between first and second dose was fairly random. So they have no idea of the optimal timing of the second dose. It’s also possible that the highest efficacy was more down to timing than dose. The MHRA will have seen every possible cut of the data and there’s bound to still be gaps. The approach does make sense to me. Go with the full dose asap (because we saw a dose response in phase II) and give the second dose up to 12 weeks later.
There was a single dose cohort right? It’d be nice to see the severe case count in that arm. Like someone above said, I’d be happy to see the severe cases fall as a first step.
From memory, severe cases came down for all regimes. Might even have been no severe cases in any of the vaccine arms? Could be wrong though. Would need to check the paper again. It was badly written, which didn’t help. Might be more clearly laid out in MHRA submission. Which should be online somewhere.
I think it's more a case that the longevity is unknown. They can look at antibody levels and T cells etc, and they can see that there's still immunity there - which apparently there is. What they can't prove is how that affects real world efficacy.
In effect, they don't know for sure if they've trained the immune system to respond to the virus. Or if the vaccine provoked people to make antibodies to the vaccine itself - but not to remember how to make more of them when a real virus arrives.
There are technical reasons (people developing immunity to the adenovirus bit of the vaccine) to think that AZ can't be used over and over again, like an annual flu shot. Again not proven yet.
Just another part of the picture when it comes to looking at why we need to have multiple vaccines available. Also, part of the reason why there's a suggestion that a single AZ dose followed by a Sputnik (or other) vaccine might give the best results. That's going to be trialled as well.
Great news. Now let’s hope they don’t feck up the distribution & roll out.
If AZ can supply 2 millions vaccines a week, that’s how many people we should be vaccinating a week. If this pandemic has shown anything though, it’s that this Government don’t have a great record when it comes to logistics.
Shouldn't they already be rolled out if he government were so confident in getting it approved?
An important thing to note about this is it still takes a couple of weeks for the protection to kick in after the first dose.
In the case of the Pfizer vaccine, it looks to take around 12 days after the initial dose until the patient receives a protective effect of around 52% efficacy. Source: https://www.bmj.com/content/371/bmj.m4826
“Call in the Army” is always such a cringe expression but it’s the perfect example of when that should be used. The forces have amazing logistics for all their faults. The entire operation should be handed over and dealt with entirely between them and AZ.
In reality what will happen is Hancock will want to have a big hand in it, will delegate the logistics to a Tory peer’s shoe lace manufacturing firm which has no factories or warehouses and will only use the Army for administering. There will then be stories of the Army on standby but never getting a call to actually do any work as we deliver 500,000 doses a week and find out that the government has actually handed over 1.5m doses per week to the EU in exchange for 3m tonnes of Ling and Rock Salmon per year to add to the UK quotas.
I'm hoping that we'll see a campaign to vaccinate the people giving the jabs as well. The Pfizer apparently starts working fast - so that's probably the way to go. It'll be interesting to see how they propose to dispense the two vaccines. I'm guessing the Pfizer will be hospital dispensed and the AZ will be everywhere else.
The AZ really is a game changer. The timings and logistics are much simpler than those for Pfizer. Suddenly you can talk about giving a visiting nurse or doctor a bag of vaccines (and an EpiPen!) to take to a nursing home or even on home visits.
I also think we'll see the sports halls etc come into service. Personally I think we'll see what amount to drive through vaccination centres come into play very quickly.
That said, based on how slow/poor the online test booking system and the covid app etc were when they went into service - the initial appointment/recording system might be another flop. Fingers crossed that people actually don't end up getting missed or double booked by their GPs surgery and the bulk vaccination centres, and that centres are kept appropriately busy. Maybe they've already written/tested it all and will impress me by rolling it out at the weekend
Great news re Oxford/AZ Vaccine.
Interested to learn more about what doses will be given - or if they even know what they should be giving and when for the vaccine to have maximum impact.
Interested to learn more about what doses will be given - or if they even know what they should be giving and when for the vaccine to have maximum impact.
No single dose cohort in their phase II/III trials, the single dose was only tested among a much smaller sample size in phase I/II. Here's their phase III publication with the relevant segment:
This is what they said about the dosage back in July:
So we don't know what kind of protection the 1 dose offered because they just assessing its safety profile and immunogenecity at that point. We know it is safe but their conclusion was essentially that it didn't generate a satisfactory immune response. Hence why they changed three trials from a single dose to a double dose only after checking out this data, in such a haphazard way. They decided not to even leave one arm to test the one dose option. That haphazard response is another one of those "serendipitous" moments that does give us some insight into how long the optimal time is between doses. But again because that wasn't a tightly controlled variable in a perfectly designed experiment, a straight comparison between dosing time period A and dosing time period B won't tell you which is better because there will be other variables that are hard to control for in the analysis stage.
And for Pfizer, the first dose was almost half as effective (52%) before the second dose. If that was true for this one, and Oxford are only going with their 62% effective plan (the half dose is off the table until US trials), then 30% efficacy is right on the threshold of being deemed too ineffective for distribution.
https://www.bbc.co.uk/news/health-55280671
So they've gone for two full doses, so the effectiveness is 62% as we said.
I just post half speculative info here so that you can come in and correct me with awesome citations and relevant data.
I would correct you on the last point though. Pfizer measured the single dose efficacy from day 0 to get the 52 percent number. Their FDA submission had a single dose efficacy measure after day 14 when the vaccine kicks in fully, and it had a 90 percent efficacy. I will find the source for this later and provide it to you.
Yep, bingo. Really the Government should have already been planning all of this and have it ready to roll out next week. If we aren’t vaccinating people as quickly as AZ can supply the vaccines, it’s a failure in the rollout.
We should be doing whatever it takes. Using the army, pharmacists, creating large temporary
vaccination centres all across the country and training people to administer the vaccines.
If we can vaccinate 2 million a week instead of 1 million, the benefits are enormous. Huge boosts for public health, the NHS, the economy. We need to be ambitious.
I'd just read that comment from the science editor in the BBC here, but then I realised I still have the Pfizer doc open in one of my tabs. Here's their data:
So they weren't so specific in their summary analysis of when it gets to around 52%, they just said in the phase between dose 1 and dose 2, but around 14 days does seem to be the point where something happens in the chart!
In terms of the dosage timing, we know from this (page 12) that c. 1,500 of the 3,500 UK participants got it 12+ weeks after the first dose, so there is plenty of data on it. Not a lot of hopeful evidence in there that the first dose is all that effective given they only show the data starting from 14 days following the second dose (page 13), and even 24 days after dose 2 - in many cases, nearly 4 months after dose 1 - there isn't a whole lot separating the placebo and vaccine groups. 14 days after dose 2, there is nothing separating them - the vaccine group is marginally worse. It's the supplementary evidence from their Lancet publication.
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Good question. Anyone ?
Won't work as a treatment because it's just doing what your immune system is already doing at that point, and your immune system has a big head start. The indications are the Pfizer vaccines properly kick in for most people after 2 weeks, at which point the disease has already gotten to a critical level. AstraZeneca's seems to work a bit later, and even if Moderna's works a bit quicker, it will always be behind your immune system.
The vaccine just inserts the key antigen into your body without any of the elements of the virus that spread the disease, but if you already have the disease, you already have the exact same antigen and the immune system is already working away to fight it. It doesn't give your immune system any additional support, it just gives it an early heads up without any of the actual virus threat. The vaccines do generate a greater immune response than exposure to the virus in some cases, for some vaccines, but the time delay makes that kind of redundant.
What you want instead is the monoclonal antibodies. Instead of sparking your own immune system into action with the antigen, which eventually sends out the call for antibodies to attack it, monoclonal antibodies are extra antibodies injected into your body that get to work straight away to support the immune system. That's what Trump got. Very expensive so not a suitable treatment to turn the tide here.
There are two clinical trials of an AZ antibody cocktail underway in the UK at present.
The first a pre-infection mix that could do the job of a vaccine in people who vaccines are ineffective on (compromised immune systems)
https://www.nihr.ac.uk/news/uk-stud...razenecas-covid-19-antibody-combination/26275
The other a just-got-infected mix for people who've tested positive or who are at extremely high risk (vulnerable person in a household with someone who has tested positive) - but who aren't yet seriously ill (similar to the Trump situation)
https://news.sky.com/story/covid-19...nt-illness-in-those-recently-exposed-12172623
Trials of antibody mixes on people who are already seriously ill have basically stopped for now. Not enough evidence that they work - some suspicion that they might contribute to virus mutations in hospitalised patients.
Thanks. I suppose the treatment Trump got wouldn’t be available at scale to the general public, at least not for some time.
In the UK, the role for it that they're looking at would be very specific I think. Mostly people who can't take a vaccine, or who have no response to vaccines - that's particularly patients undergoing certain cancer treatments and some other subsets of people with compromised immune systems or auto-immune disease.
In the prophylactic form they would basically be used as a vaccine that needs topping up every few months.
In the post-infection form - the idea would be as soon as someone tests positive (or if someone in their household or care bubble does) you'd give them the antibody dose as a first response treatment.
On the face of it, it might take so long for them to complete statistically valid placebo controlled clinical trials of the treatment option that they are only use it on an emergency basis, assuming it does no harm and seems to do some good. They may get more data for the vaccine-alternative version, but again it might take them a long time to get the trial numbers/cases to actually make it a standard prescription.
Surely a massive game changer that. You can lift restrictions a month earlier if you're confident they'll be no major risk from covid from first dose rather than badly need a second dose before you can tick that person off the list.
Little bit more optimistic now we can have a relatively normal May-October (what's this sudden thing of naming parts of the year after namesake cruise ships all about?
) if the roll up is scaled up as promised by the government e.g. 1m + doses a week.https://www.gov.uk/government/publi...professionals-on-covid-19-vaccine-astrazeneca
The table at 5.1 is a bit unreadable..
The table at 5.1 is a bit unreadable..
Did I mishear Hancock just now? He said we have over half a million ready to go and million more in Feb. So is that meaning it's only 500k till then?
They’ll need time to train staff before deployment, difficult to do over a Christmas period.
Fingers crossed!
This sounds pretty good:
The immunogenicity data does look promising on both fronts. 15x the number of antibodies 28 days after dose 1 vs unvaccinated folks, and 3-8x more for the second dose depending on the dosing wait time (longer = higher). From memory that’s a very healthy amount after the first dose even vs. a couple of vaccines already approved in China and Russia.
https://assets.publishing.service.g...essionals_on_COVID-19_Vaccine_AstraZeneca.pdf
The PDF has a much better formatted table. See table 2.