Getting Both AZ & Pfizer

[Chalkie]

Despite the claims from some on this thread to the contrary there are studies that show that Pfizer and Moderna outlast AZ in the real world.

Perhaps you could provide some citations for those studies. And do they address surface antibody vs longer term T-cell protection?

For the benefit of everyone, here's a list of the studies on heterologous prime boosting (aka mixing vaccines). These studies suggest that heterologous dosing is as, or potentially more, effective than homologous dosing. None of the studies identified any safety signals. Mixing AZ + Pfizer (or AZ + Moderna) is a highly effective and protective approach, and on the basis of the British Columbia study below, better than Pfizer alone and on par with Moderna alone.

Most recently, from British Columbia using real world data (Skowronski DM, Setayeshgar S, Zou M et al. Two-dose vaccine effectiveness against SARS-CoV-2 infection and hospitalization, including Delta variant: a test-negative design in British Columbia, Canada (BC real world study)) in a sample size of 246,565 people showed that AZ+mRNA was the most effective combination in relation to all and Delta hospitalisations, and on par with Pfizer for all and Delta infections, and a percent or two behind Moderna (which had the best outcomes on all measures) for all and Delta infections:



To virtually identical effect from Quebec: Efficacité de deux doses de vaccin contre la COVID-19 chez les adultes québécois vivant dans la communauté | INSPQ.

And these are the prior studies on heterologous prime boosting.

Study	Population	Product	Schedule	Primary Endpoint	Results
(Borobia, Carcas et al. 2021)	676 COVID naïve people 18-60 years of age randomised to two vaccine doses or a single vaccine dose from 5 hospitals in Spain	ChAdOx1 BNT162b2	ChAdOx1 (day 0) BNT162b2 (8-12 weeks)	Antibody levels at 14 days post second dose	37-fold increase in Binding Antibody Units per mL after second dose compared to single dose.
(Dimeglio, Herin et al. 2021) PREPRINT	66 HCW in France given the choice of homologous or heterologous vaccination with ChAdOx1 or BNT162b2	ChAdOx1 BNT162b2	Not recorded but either ChAdOx1/ChAdOx1 BNT162b2/BNT162b2 ChAdOx1/BNT162b2	Neutralising antibody titres on live virus assay 1 month after vaccination	ChAdOx1/BNT162b2 produced a higher proportion of subjects with >2 fold increase in antibody titres 1 month after vaccination (95.4%) compared to either homologous dose, ChAdOx1 63.6% and BNT162b2 68.2% respectively
(Hammerschmidt, Bosnjak et al. 2021)	Plasma from 85 individuals who had either received ChAdOx1/ChAdOx1 or ChAdOx1/BNT162b2	ChAdOx1 BNT162b2	Not recorded	Neutralising antibody titre against Delta strain at a mean of 17 days after second vaccine dose	Heterologous dosing resulted in a significantly higher neutralising titre than homologous ChAdOx1 dosing, but similar to homologous BNT162b2 dosing
(Hillus, Schwarz et al. 2021)	340 HCW vaccinated at a university hospital in Germany	ChAdOx1 BNT162b2	BNT162b2/BNT162b2 day 0 and 21 ChAdOx1/BNT162b2 day 0 and Week 8-12	IgG seroconversion and neutralising antibodies is COVID S1 protein three weeks after second dose	Neutralising antibodies were present in 100% of homologous and 99% of heterologous dose recipients
(Liu, Shaw et al. 2021)	Randomised phase 2 trial in 830 COVID naïve patients >50 years of age in UK	ChAdOx1 BNT162b2	ChAdOx1/ChAdOx1 ChAdOx1/BNT162b2 BNT162b2/ChAdOx1 BNT162b2/BTN162b2 All Day 0 and Day 28	Serum anti-spike IgG concentration 28 days after second dose	ChAdOx1/BNT162b2 was statistically superior to ChAdOx1/ChAdOx1. The two BNT162b2/ChAdOx1 was inferior to BNT162b2/BNT162b2.
(Tenbusch, Schumacher et al. 2021)	Plasma from 480 individuals who had received either homologous or heterologous vaccination	ChAdOx1 BNT162b2	ChAdOx1/ChAdOx1 ChAdOx1/BNT162b2 BNT162b2/BTN162b2 Interval not recorded	Neutralising antibodies	Heterologous ChAdOx1/BNT162b2 produced higher antibody levels than either homologous schedule, and similar to homologous BNT162b2 (at a shorter interval of 21 days)
(Normark, Vikstrom et al. 2021)	Correspondence regarding analysis of plasma from 88 HCW who had received either homologous or heterologous vaccination recruited from ongoing trial.	ChAdOx1 mRNA-1273	ChAdOx1/ChAdOx1 ChAdOx1/mRNA-1273 Day 0 and week 9-12.	Neutralising antibodies on live virus assay 1 month after second dose	Data not numerically presented. Both homologous and heterologous schedules induced neutralising antibodies but the heterologous dose had higher levels. ChAdOx1/ChAdOx1 did not produce neutralising antibodies against Beta strain, while the heterologous schedule did
(Yorsaeng, Vichaiwattana et al. 2021) PREPRINT	234 HCW who opportunistically received homologous or heterologous doses depending on vaccine availability in Thailand	ChAdOx1 Coronavac	ChAdOx1/ChAdOx1 (n=80) Day 0 and Week 10 Coronavac/Coronavac (n=80) Day 0 and Week 3 Coronavac/ChAdOx1 (n=54) Day 0 and 4 weeks	Serum anti-spike antibodies compared to COVID convalescent serum	The GMT of antibodies after Coronavac/Coronavac was 96.4U/mL and not not significantly different from convalescent serum. The GMT of antibodies after heterologous dosing was 797U/mL and similar to 2 doses of ChAdOx1 (818U/mL)

 

[drron]

Thanks @Chalkie

 

[Pushka]

I'm booked in for Pfizer at the 6th month mark after second AZ. In early December.

 

[Lynda2475]

I have previously posted links to study re long term effectiveness of mrna vaccines. Your can search the forums.

MRNA are the preferred booster technology, including in the study you posted. And mrna boosters are what our government has ordered and most people will get. The AZ fans here trying to scare people off mrna are doing damage.

There have been zero deaths from mrna vaccines in Australia and the majority of doses given have been mrna. We would still be facing months of lockdown if AZ was the only option used, as far fewer people would be fully vaccinated.

 

[Chalkie]

MRNA are the preferred booster technology, including in the study you posted. And mrna boosters are what our government has ordered and most people will get. The AZ fans here trying to scare people off mrna are doing damage.

The studies show that the combination of AZ + mRNA in a heterologous two dose regimen produces a more effective immunological outcome. The heterologous dosing studies say nothing about mRNA being a preferred booster. If you have any studies which address mRNA vaccines being the preferred booster in all circumstances for existing dosing regimens, feel free to share them.

No one is trying to scare people off mRNA vaccines, and giving people access to all of the studies so they can read them for themselves does no damage, save to the extent that it undermines any agendas, that are without scientific basis, to prefer in all circumstances mRNA vaccines over AZ. AZ is a safe and effective vaccine (as has been demonstrated over and over again), and the studies I've cited demonstrate that a combination of AZ + mRNA in a two dose regimen produces an immunological outcome that is at least effective as mRNA alone and in the case of the British Columbia study, more effective than Pfizer alone in a two dose regimen.

 

[DC3]

… No one is trying to scare people off mRNA vaccines, and giving people access to all of the studies so they can read them for themselves does no damage, save to the extent that it undermines any agendas, that are without scientific basis, to prefer in all circumstances mRNA vaccines over AZ …

Exactly. Thank you.

 

[OATEK]

The AZ fans here trying to scare people off mrna are doing damage.

I have no doubt that people have died because of the AZ scare campaign - to say that people are trying to do the same thing with mRNA simply by stating that a mix of AZ & PZ might give the best long term protection is at best laughable.

Family friend and GP has already said to us (both 2jab AZ) that she has AZ in the fridge that will have to be thrown out in Feb, and that we should duck in before then for a booster prior to the trip to the UK in March. As I am in 1B then I will probably have access to an mRNA booster before the trip, but perhaps will get the AZ instead rather than see it wasted given I see no real advantage as yet to mixing the AZ/PZ. I certainly won't head off overseas without a booster though, as I said on another thread the UK will be coming off their winter and there will likely be lots of Covid about.

 

[Pushka]

I have no doubt that people have died because of the AZ scare campaign - to say that people are trying to do the same thing with mRNA simply by stating that a mix of AZ & PZ might give the best long term protection is at best laughable.

Family friend and GP has already said to us (both 2jab AZ) that she has AZ in the fridge that will have to be thrown out in Feb, and that we should duck in before then for a booster prior to the trip to the UK in March. As I am in 1B then I will probably have access to an mRNA booster before the trip, but perhaps will get the AZ instead rather than see it wasted given I see no real advantage as yet to mixing the AZ/PZ. I certainly won't head off overseas without a booster though, as I said on another thread the UK will be coming off their winter and there will likely be lots of Covid about.

It doesnt seem like we have a choice in SA, and my GP clinic never provided Covid vaccinations so I've had to go to a Hub as I cant be bothered setting up with another GP. Also in 1B.

 

[DC3]

When my opportunity to get the booster arrives, I’ll take whatever I can get.

 

[coriander]

I think I may be getting the quadrella: I've had 2xAZ vaccines (May&Aug), third dose of Moderna in early October ('cos I'm immunocompromised) and then will probably get booster of PF in April 2022.

 

[Lynda2475]

the studies I've cited demonstrate that a combination of AZ + mRNA in a two dose regimen produces an immunological outcome that is at least effective as mRNA alone and in the case of the British Columbia study, more effective than Pfizer alone in a two dose regimen.

You have not provided data re doses of an MRNA followed up by a 6 month MRNA booster which is what most Australians will actually receive.

Using AZ as a booster for those double vaxed with an MRNA is not standard practice anywhere.

 

[drron]

Actually at the moment boosters are not the standard practice in most countries.Both the CDC and the UK authorities say for the majority of citizens may have a booster.Not recommended or should.

 

[Lynda2475]

UK is allowing boosters for anyone over the age of 50. In US anyone over 60 can get one + anyone who is imuno compromised or works in a job where they may be exposed (a low bar to meet).

A friend got her 3rd Moderna yesterday in the USA and only had to state her job was public facing (as most jobs are), no drama at all - yet by your reckoning that isn't recommended. Whereas in reality pretty much anyone who wants one can get one in the US right now.

Friends working in USA in medical field (including a radiographer and a EMT) got their boosters in September (9 months post dose 2) before any FDA announcement.

 

[OATEK]

Actually at the moment boosters are not the standard practice in most countries.Both the CDC and the UK authorities say for the majority of citizens may have a booster.Not recommended or should.

UK is allowing boosters for anyone over the age of 50. In US anyone over 60 can get one + anyone who is imuno compromised or works in a job where they may be exposed (a low bar to meet).

A friend got her 3rd Moderna yesterday in the USA and only had to show her job was public facing, no drama at all. Friends working in USA in medical field (including a radiographer and a EMT) got their boosters in September (9 months post dose 2).

Thanks for confirming Drrons statement, that boosters are not recommended for the majority of citizens. We will have a booster knowing that we will go from a low Covid environment to a high incidence location.

 

[Lynda2475]

That's not what I did, my post shows how wide the eligibility already is, especially in the USA where if you state your job exposes you to covid (which is almost every job) because covid is everywhere, but whatever.

Sensibly we are able to get a booster at 6 months and I will be doing so every 6 months so I can travel with confidence.

 

[drron]

That's not what I did, my post shows how wide the eligibility already is, especially in the USA where tif you state your job exposes you to covid (which is almost every job) because covid is everywhere, but whatever.

Sensiblt we are able to get a booster at 6 months and I will be doing so every 6 months so I can travel with confidence.

But you ignore the fact that boosters aren't recommended for the majority of the population.
Allowing people to have them is a very different thing.but then you really do like to have the last word even if it is totally irrelevant.

Oh and by the way I am treating a fellow who has just had his second episode of Plasmapheresis for his Guillain Barre developed 3 days post first Pfizer jab.

 

[jakeseven7]

Perhaps you could provide some citations for those studies. And do they address surface antibody vs longer term T-cell protection?

For the benefit of everyone, here's a list of the studies on heterologous prime boosting (aka mixing vaccines). These studies suggest that heterologous dosing is as, or potentially more, effective than homologous dosing. None of the studies identified any safety signals. Mixing AZ + Pfizer (or AZ + Moderna) is a highly effective and protective approach, and on the basis of the British Columbia study below, better than Pfizer alone and on par with Moderna alone.

Most recently, from British Columbia using real world data (Skowronski DM, Setayeshgar S, Zou M et al. Two-dose vaccine effectiveness against SARS-CoV-2 infection and hospitalization, including Delta variant: a test-negative design in British Columbia, Canada (BC real world study)) in a sample size of 246,565 people showed that AZ+mRNA was the most effective combination in relation to all and Delta hospitalisations, and on par with Pfizer for all and Delta infections, and a percent or two behind Moderna (which had the best outcomes on all measures) for all and Delta infections:
View attachment 263318
View attachment 263319

To virtually identical effect from Quebec: Efficacité de deux doses de vaccin contre la COVID-19 chez les adultes québécois vivant dans la communauté | INSPQ.

And these are the prior studies on heterologous prime boosting.

Study	Population	Product	Schedule	Primary Endpoint	Results
(Borobia, Carcas et al. 2021)	676 COVID naïve people 18-60 years of age randomised to two vaccine doses or a single vaccine dose from 5 hospitals in Spain	ChAdOx1 BNT162b2	ChAdOx1 (day 0) BNT162b2 (8-12 weeks)	Antibody levels at 14 days post second dose	37-fold increase in Binding Antibody Units per mL after second dose compared to single dose.
(Dimeglio, Herin et al. 2021) PREPRINT	66 HCW in France given the choice of homologous or heterologous vaccination with ChAdOx1 or BNT162b2	ChAdOx1 BNT162b2	Not recorded but either ChAdOx1/ChAdOx1 BNT162b2/BNT162b2 ChAdOx1/BNT162b2	Neutralising antibody titres on live virus assay 1 month after vaccination	ChAdOx1/BNT162b2 produced a higher proportion of subjects with >2 fold increase in antibody titres 1 month after vaccination (95.4%) compared to either homologous dose, ChAdOx1 63.6% and BNT162b2 68.2% respectively
(Hammerschmidt, Bosnjak et al. 2021)	Plasma from 85 individuals who had either received ChAdOx1/ChAdOx1 or ChAdOx1/BNT162b2	ChAdOx1 BNT162b2	Not recorded	Neutralising antibody titre against Delta strain at a mean of 17 days after second vaccine dose	Heterologous dosing resulted in a significantly higher neutralising titre than homologous ChAdOx1 dosing, but similar to homologous BNT162b2 dosing
(Hillus, Schwarz et al. 2021)	340 HCW vaccinated at a university hospital in Germany	ChAdOx1 BNT162b2	BNT162b2/BNT162b2 day 0 and 21 ChAdOx1/BNT162b2 day 0 and Week 8-12	IgG seroconversion and neutralising antibodies is COVID S1 protein three weeks after second dose	Neutralising antibodies were present in 100% of homologous and 99% of heterologous dose recipients
(Liu, Shaw et al. 2021)	Randomised phase 2 trial in 830 COVID naïve patients >50 years of age in UK	ChAdOx1 BNT162b2	ChAdOx1/ChAdOx1 ChAdOx1/BNT162b2 BNT162b2/ChAdOx1 BNT162b2/BTN162b2 All Day 0 and Day 28	Serum anti-spike IgG concentration 28 days after second dose	ChAdOx1/BNT162b2 was statistically superior to ChAdOx1/ChAdOx1. The two BNT162b2/ChAdOx1 was inferior to BNT162b2/BNT162b2.
(Tenbusch, Schumacher et al. 2021)	Plasma from 480 individuals who had received either homologous or heterologous vaccination	ChAdOx1 BNT162b2	ChAdOx1/ChAdOx1 ChAdOx1/BNT162b2 BNT162b2/BTN162b2 Interval not recorded	Neutralising antibodies	Heterologous ChAdOx1/BNT162b2 produced higher antibody levels than either homologous schedule, and similar to homologous BNT162b2 (at a shorter interval of 21 days)
(Normark, Vikstrom et al. 2021)	Correspondence regarding analysis of plasma from 88 HCW who had received either homologous or heterologous vaccination recruited from ongoing trial.	ChAdOx1 mRNA-1273	ChAdOx1/ChAdOx1 ChAdOx1/mRNA-1273 Day 0 and week 9-12.	Neutralising antibodies on live virus assay 1 month after second dose	Data not numerically presented. Both homologous and heterologous schedules induced neutralising antibodies but the heterologous dose had higher levels. ChAdOx1/ChAdOx1 did not produce neutralising antibodies against Beta strain, while the heterologous schedule did
(Yorsaeng, Vichaiwattana et al. 2021) PREPRINT	234 HCW who opportunistically received homologous or heterologous doses depending on vaccine availability in Thailand	ChAdOx1 Coronavac	ChAdOx1/ChAdOx1 (n=80) Day 0 and Week 10 Coronavac/Coronavac (n=80) Day 0 and Week 3 Coronavac/ChAdOx1 (n=54) Day 0 and 4 weeks	Serum anti-spike antibodies compared to COVID convalescent serum	The GMT of antibodies after Coronavac/Coronavac was 96.4U/mL and not not significantly different from convalescent serum. The GMT of antibodies after heterologous dosing was 797U/mL and similar to 2 doses of ChAdOx1 (818U/mL)

But you ignore the fact that boosters aren't recommended for the majority of the population.
Allowing people to have them is a very different thing.but then you really do like to have the last word even if it is totally irrelevant.

Oh and by the way I am treating a fellow who has just had his second episode of Plasmapheresis for his Guillain Barre developed 3 days post first Pfizer jab.

Don’t even bother…. I think to myself this every time false and misleading information is posted… but then I worry other forum members might actually believe the poster so have to correct… decisions decisions

 

[Chalkie]

You have not provided data re doses of an MRNA followed up by a 6 month MRNA booster which is what most Australians will actually receive.

Using AZ as a booster for those double vaxed with an MRNA is not standard practice anywhere.

And I didn't provide data showing that two doses of AZ followed by a six month mRNA booster produces an effective immunological outcome. So what? But on the basis of the one dose AZ + mRNA studies, there's nothing in terms of safety signals or immunological outcomes to suggest that won't be an appropriate regimen.

Pfizer has announced the results of its trials using its own vaccine as a booster shot. Unsurprisingly, it showed excellent efficacy (which you will know from your studies of these matters is quite different from effectiveness). The US FDA authorised the use of Moderna as a booster by reviewing the original clinical trial data which included 149 people (yes, only 149 people) who had booster shots, and that also, completely unsurprisingly, showed excellent efficacy. Again, as you know from your studies of these matters, efficacy is not the be-it-and-end-all. Effectiveness in the real world is equally, if not more, important.

And apropos the effectiveness of using a different vaccination mechanism, given the soundness of the scientific basis for heterologous prime boosting, the US FDA on 20 October 2021 authorised using an adenovirus vector vaccine (like AZ) as a booster shot for double mRNA vaccinated persons. In the US, that will be the Johnson & Johnson/Janssen vaccine, which like AZ uses an adenovirus vector. So that effective combination is able to be used, at least in the US, as "standard practice".

 

[Chalkie]

That's not what I did, my post shows how wide the eligibility already is, especially in the USA where tif you state your job exposes you to covid (which is almost every job) because covid is everywhere, but whatever.

Sensiblt we are able to get a booster at 6 months and I will be doing so every 6 months so I can travel with confidence.

Why don't you post the actual FDA booster eligibility criteria for which EUA has been granted? Because they are not what you or your anecdotes about booster shots in the US say they are.

 

[Chalkie]

Don’t even bother…. I think to myself this every time false and misleading information is posted… but then I worry other forum members might actually believe the poster so have to correct… decisions decisions

False and misleading information, at least in relation to Covid-19 vaccines, is very easily corrected, and it is worthwhile correcting it so people have access to useful information on which they can make informed decisions.