Second vaccine dose timing

Agree with all that ?

Fair enough, I get your point. I shouldn't have used the word "data" in my post this afternoon, I can see what you mean. But there was a good reason for taking the route we did, and it wasn't just to get the government out of a hole or to to let them be able to show what a big number of jabs we've delivered. I think it's the right decision and now we're seeing other academics support it.

I've also seen a WHO person say it was the right decision too, but I haven't posted that because the WHO aren't so popular on here, especially the person who said it!

Alegrias1

I'm not being funny - I just know not to get into an argument I'd lose.

But I am heartily fed up of the notion that it was the government who made this decision in order to improve their ratings when there was a very good scientific rationale for doing it. And this paper seems to reinforce that decision, and its not UK based.

I’ve never thought that - I thought they did it because we were in a right mess and it was the least worst option. It doesn’t make it an evidence based decision but one based on necessity rooted in sound theory. If we start making data and theory interchangeable, why bother with research at all? Yes I know that’s a bit extreme but you know what I mean.....

I'm not being funny - I just know not to get into an argument I'd lose.

But I am heartily fed up of the notion that it was the government who made this decision in order to improve their ratings when there was a very good scientific rationale for doing it. And this paper seems to reinforce that decision, and its not UK based.

Alegrias1

I'm not even going to get into this conversation, because I know your background suzie and I expect you could run rings round me. But this shows that there are scientists in countries other that the UK who are saying that the longer dose with Pfizer is the right way to go.

So we can maybe put a halt to the idea that the government are doing it for Brownie points?

Don’t be like that - I accept the idea that a longer dosing interval has much merit and especially in a country where infection levels are still high. But I don’t accept this argument being wrapped up and presented as based on anything other than a theoretical derivation no matter how well founded.

I'm not even going to get into this conversation, because I know your background suzie and I expect you could run rings round me. But this shows that there are scientists in countries other that the UK who are saying that the longer dose with Pfizer is the right way to go.

So we can maybe put a halt to the idea that the government are doing it for Brownie points?

Alegrias1

Bringing an old thread back to life....

Researchers publish a paper in the New England Journal of Medicine with data that supports the longer dosing interval for the Pfizer vaccine and urging the US to adopt this to save thousands of COVID-19–related hospitalizations and deaths this winter in the United States

www.nejm.org/doi/full/10.1056/NEJMc2036242

I’m not getting this - where’s the data on a gap longer than 2/3 weeks as opposed to a theoretical derivation?

Bringing an old thread back to life....

Researchers publish a paper in the New England Journal of Medicine with data that supports the longer dosing interval for the Pfizer vaccine and urging the US to adopt this to save thousands of COVID-19–related hospitalizations and deaths this winter in the United States

www.nejm.org/doi/full/10.1056/NEJMc2036242

Here's an article that explains things quite well.

blogs.sciencemag.org/pipeline/archives/2020/11/23/oxford-az-vaccine-efficacy-data

The thing with the AZ vaccine and over 65s is a weird one. Not sure I entirely understand it, but I believe it was to do with second level research exploring dosage and dosage interval rather than the first level efficacy and safety research. For some reason they did not include over 65s in the study, therefore their findings weren't applied to that group - not because there is no evidence that it works, but because it would be unethical to pretend that group was included in the study. Equally, the results are generalisable to that group, so there is no evidence that they are adversely affected by dose/interval. I'll try to go back and find the evidence for that and post the link.

Rosie51 I note that you are a statistician so I have a bit of reluctance in putting this forward, but here goes anyway....

Let's assume that the figures are about right and you only get 50% protection with the first dose, even though as NellG says the figures are far from robust. Pfizer claim about 90% after 2 doses.

So say you have 10,000 people and 10,000 doses to distribute among them. The options are that everybody gets one dose and has to wait 12 weeks for the next, or 5,000 people get two doses within 3 weeks.

I don't know what the chance of getting Covid is for unvaccinated over 80s, but lets say 1% because its easy to calculate. Its probably much less than that.

Then with the one dose option 50 people get Covid within the 12 weeks. (10,000 people with 50% protection) With the two dose option 55 people get Covid within the next 12 weeks. (5000 people with 90% protection and 5000 with none at all.) That's a 10% increase and scales up to large numbers.

Now I know its more complicated than that and that more doses are coming available all the time, and the powers that be have better models than me with a spreadsheet, but I can understand why the decisions have been taken on public health grounds.

NellG, I do understand the limitations of the research, (background many, many years ago in statistics), but as there can be no harm in sticking to the timetable the manufacturers recorded their data from, and possibly harm from deviating wildly from this, I have to support shortening the 12 week gap, and not just on moral grounds. I note that much of Europe is stating there's not the scientific evidence to confirm the AZ vaccine is suitable for over 65s and some are saying younger than that. Our interpretation of the data seems to be at odds with theirs. Same science, different conclusions.

Rosie51 ( and anyone else)- I absolutely understand your concern, however the primary weakness of this research is the small sample size, and the use of the word median - half of the 23 subjects were under the age of 80.

This might sound like pedantry but what it means is that the result of this research is not generalisable to the whole population. The only thing this research tells us is that the topic needs more research before it can be deemed fact and that the major indicator is that vaccine developers will need to anticipate mutations and variants.

As a piece of quantitative research it's not robust enough to standalone and needs to be supported by further research. It really shouldn't be used as evidence of anything other than the need for more study with a larger sample and more attention to the variables.

I agree that the over 80's should have the full dose ASAP - my agreement is moral. There is just not enough science (yet) to support it on any other level.

Alegrias1 I still think they should do everything possible to protect the 50% of over 80s who won't have sufficient protection after one dose, when 100% of them did after the second dose. How many are going to add to our death toll quite unnecessarily?

Oops - cross-post Rosie51

Actually after re-reading I see I have got that wrong - its not just against the E484K mutation.

Always happy to admit when I make a mistake :-). Still don't think they should change the dosing schedule yet though.

Having had my first dose of the Pfizer vaccine two weeks ago, I do not intend to change my ultra-cautious behaviour until at least three weeks after my second dose, which I hope I will get within the next ten weeks as promised.

Although I was impressed with the efficient organisation of our vaccinations, no-one told me that.

I think that when waiting for fifteen minutes after vaccination we should be clearly instructed to keep vigilant until at least three weeks after the second dose. Although we may have some measure of protection from the first dose, we could put others at risk by taking risks ourselves, so we need to minimise contacts, keep our distance and wear a mask.

That's not how I'm reading it Alegrias the study was using the B.1.1.7 variant.

From the study which I linked to

“Of particular concern, though, is the emergence of the E484K mutation, which so far has only been seen in a relatively small number of individuals. Our work suggests the vaccine is likely to be less effective when dealing with this mutation.

I personally don't think it is a good reason to change anything right now Rosie51, and here's why.

The reduced efficacy is only shown with the E484K mutation which is currently not prevalent at all in the population of this country. Assuming that the results can be scaled up and the 50% still holds then of the people who have had the vaccine, 50% of them are protected against a mutation that is not prevalent and something like 90% of them are protected against the other variants.

The more people who get vaccinated with even one dose, the less chance there is of the virus killing people. The recommendation may change in the future, but right now I can understand why they don't want to change. Other people may have a different viewpoint.

I included the Times headline because it seemed to me that the press - again - are focussing on the negative when the whole story is actually positive. Like you say, they never tell the whole story.

Alegrias1

I know I said I'd step back but I'm just a glutton for punishment....

Headline from the Cambridge study: Pfizer BioNTech vaccine likely to be effective against B1.1.7 strain of SARS-CoV-2

Hooray!!

In their article, Cambridge says that scientists have shown that in in-vitro lab tests, just under 50% of the 15 over-eighties they tested developed enough neutralising antibodies for mutation E484K after one jab. Antibodies are only one way that the body fights infection. Six months ago we would have given our right arms for 50% protection.

Headline in today's times: Single dose of Pfizer-Biontech vaccine may not protect elderly from Covid-19 infection

Boo!!

www.cam.ac.uk/research/news/pfizer-biontech-vaccine-likely-to-be-effective-against-b117-strain-of-sars-cov-2

The seven individuals who were unable to neutralise the virus after the first dose were all aged over 80 years old. This accounts for almost half of the 15 individuals in this age group. However, at a follow-up visit after these individuals had received their second dose (given at three weeks), they were all able to neutralise the virus.

Dr Dami Collier, the main co-investigator on the studies, added: “Our data suggest that a significant proportion of people aged over eighty may not have developed protective neutralising antibodies against infection three weeks after their first dose of the vaccine. But it’s reassuring to see that after two doses, serum from every individual was able to neutralise the virus.”

I'd suggest this is a reason not to delay the second dose for 12 weeks, given it will be 15 weeks in total before the vaccine is fully effective. At the very least over 80s should be given the second dose at the 3 week mark. Maybe other age cohorts could have a slightly longer gap?

Haven't seen the Times article, but that headline is not untrue, although not telling the whole story, but when did headlines ever do so.

I know I said I'd step back but I'm just a glutton for punishment....

Headline from the Cambridge study: Pfizer BioNTech vaccine likely to be effective against B1.1.7 strain of SARS-CoV-2

Hooray!!

In their article, Cambridge says that scientists have shown that in in-vitro lab tests, just under 50% of the 15 over-eighties they tested developed enough neutralising antibodies for mutation E484K after one jab. Antibodies are only one way that the body fights infection. Six months ago we would have given our right arms for 50% protection.

Headline in today's times: Single dose of Pfizer-Biontech vaccine may not protect elderly from Covid-19 infection

Boo!!

sillydevil

Alegrias1

It's not reckless and it is good science.

I feel for these people. Trying to do their best and so much animosity comes their way. The Moderna vaccine is an mRNA vaccine, just like the Pfizer one, and it shows that you have 94% protection after 2 months and there is no theoretical reason that the immunity will fall off a cliff. His actual words. The interviewer brings up the 33% figure again - he has no no idea what that means, clearly. Or that its been debunked a few weeks ago.

Here's the guy you think is being reckless.

www.phc.ox.ac.uk/team/anthony-harnden

This makes me so angry.

Yes, I believe the JVCI and the Government are reckless gamblers. If it's good science where was the evidence or proof that contradicts the makers published data? The "there is no theoretical reason that the immunity will fall off a cliff", is there a theoretical reason it shouldn't or fade even? Why should data from Moderna be applied to Pfizer, many products have similar designs, but they don't perform in the same way. I miss the point about Professor Harnden, is it because he has many qualifications he can't be reckless? I was stating the Government and JCV1, in my opinion, are taking a reckless gamble. There are other scientists who have opposing views to those taken by the JCVI. One headline today - "Public Health England is investigating cases of coronavirus with 'worrying' new genetic changes that have been found in some regions of the UK". This fits with an excerpt from a BMJ Article 6th January - Paul Bieniasz, a retrovirologist from Rockefeller University who is studying how the virus can acquire mutations, has warned that the UK was taking a gamble that risked fostering vaccine resistant forms of the virus. He told the news site STAT, “My concern, as a virologist, is that if you wanted to make a vaccine-resistant strain, what you would do is to build a cohort of partially immunised individuals in the teeth of a highly prevalent viral infection.” As previously stated I hope their gamble pays off and I pray it does, but it is wait and see.

I think the worrying new genetic change is B1351, aka the South Africa variant. Lab tests have shown that there has been a mutation in one of the spike proteins, which reduces the immune response. In the case of the so-called Brazil variant, this is on top of the mutation already identified in the "Kent" variant. Some scientists are concerned that one dose will just not work with the new variants, so it's vital that people continue to follow non-medical precautions.

It's also why testing has been ordered for the areas where the new variant has already been identified.

Thank you Garnet25 for you accurate, concise post

Alegrias1

It's not reckless and it is good science.

I feel for these people. Trying to do their best and so much animosity comes their way. The Moderna vaccine is an mRNA vaccine, just like the Pfizer one, and it shows that you have 94% protection after 2 months and there is no theoretical reason that the immunity will fall off a cliff. His actual words. The interviewer brings up the 33% figure again - he has no no idea what that means, clearly. Or that its been debunked a few weeks ago.

Here's the guy you think is being reckless.

www.phc.ox.ac.uk/team/anthony-harnden

This makes me so angry.

Yes, I believe the JVCI and the Government are reckless gamblers. If it's good science where was the evidence or proof that contradicts the makers published data? The "there is no theoretical reason that the immunity will fall off a cliff", is there a theoretical reason it shouldn't or fade even? Why should data from Moderna be applied to Pfizer, many products have similar designs, but they don't perform in the same way. I miss the point about Professor Harnden, is it because he has many qualifications he can't be reckless? I was stating the Government and JCV1, in my opinion, are taking a reckless gamble. There are other scientists who have opposing views to those taken by the JCVI. One headline today - "Public Health England is investigating cases of coronavirus with 'worrying' new genetic changes that have been found in some regions of the UK". This fits with an excerpt from a BMJ Article 6th January - Paul Bieniasz, a retrovirologist from Rockefeller University who is studying how the virus can acquire mutations, has warned that the UK was taking a gamble that risked fostering vaccine resistant forms of the virus. He told the news site STAT, “My concern, as a virologist, is that if you wanted to make a vaccine-resistant strain, what you would do is to build a cohort of partially immunised individuals in the teeth of a highly prevalent viral infection.” As previously stated I hope their gamble pays off and I pray it does, but it is wait and see.

Urmstongran ????