[james4beach]

Speaking on the phone with family members today, I found that they have misconceptions about "comparing" Covid vaccines. The same issue has come up on CMF and I think many people have the wrong idea about these efficacy numbers.

These efficacy % numbers we hear in the media are not a useful way to compare Pfizer / Moderna / AstraZeneca:

• different trials can use different criteria / definitions
• very different demographics; different ages
• trials happened at different times in the pandemic
• and in different countries!
• variants may be present at those different times/countries

There's a great Vox video here, which I'm also pasting below. I took a graph out of the video, and added AstraZeneca's clinical trial to it. Notice how the Pfizer clinical trial was during a very different stage of the pandemic; it was an easier / lower risk environment, and few variants were present.

The AstraZeneca US clinical trial, however, occurred during the worst phase of the pandemic as shown below. It also included participants in Latin American countries, so the numbers can't be compared directly to Pfizer's trial.

Here's a good video explaining why you can't compare the vaccines

 

[newfoundlander61]

Best approach is take which ever one you can and ignore the names of them. I am 59 and had my first shot a week and a half ago.

 

[OptsyEagle]

Thanks J4B. The graph above does a lot better job explaining the conflicts involved, within the different clinical trials, then anything I was able to do. The other thing involved, that plays a huge roll, in which vaccine's "get lucky" and end up with the higher efficacy numbers is human covid intervention precautions. They played a huge roll in adjusting the numbers up and down. Those covid precautions were implemented at different times and at significantly different levels in different parts of the world. The good news is that most covid precautions should adjust the efficacy numbers lower in the trials, so in the real world without precautions the vaccines should provide equal or better efficacy results.

All the clinical trials can really do is confirm they are safe, which is the primary purpose and secondary that they are effective. Only the real world will confirm efficacy rates and so far we have had 100s of millions of people vaccinated and I have not heard of many being rushed to the hospital or dying from Covid-19.

 

[newfoundlander61]

Sometime to keep in mind, the annual Flu shot we get each year has been 40% effective, meaning it's prevented illness 40% of the time. So with that in mind the current COVID-19 Vaccines are all very good.

 

[sags]

I think the comparisons are getting ahead of the science.

The clinical trial process for the AZ has not been concluded yet.

They still need to be peer reviewed and approved by the FDA.

 

[sags]

An article from a month ago on what the FDA requires for approval.

The main question for regulators and governments today is the low efficacy rate for AZ against the virus variants, particularly against the SA variant. That is why some countries have already decided they will not use the vaccine.

This new study does not improve the efficacy rate against the variants.

The "need" for a vaccine due to shortage of the other vaccines, may prompt the FDA to approve the AZ......but if the other vaccines are sufficient to provide supply.......they may not.

We shall see.

FDA could reject AstraZeneca's COVID-19 vaccine on efficacy and manufacturing shortfalls: analyst

It was bad enough when a study released last week concluded that AstraZeneca’s COVID-19 vaccine was largely ineffective against the aggressive B.1.351 variant that recently emerged in South Africa. | It's not just the worrisome data showing AstraZeneca’s COVID-19 vaccine was largely ineffective...

www.fiercepharma.com

 

[sags]

Another article on the FDA approval from yesterday.

FDA, CDC advisers say to expect a lot of questions about AstraZeneca Covid-19 vaccine | CNN

AstraZeneca is expected to apply in the next few weeks for emergency use authorization for its Covid-19 vaccine in the US, and if and when it does, advisers to the US Food and Drug Administration and the US Centers for Disease Control and Prevention will likely have questions.

www.cnn.com

 

[MrMatt]

I think the comparisons are getting ahead of the science.

The clinical trials for the AZ have not been concluded yet.

They still need to be peer reviewed and approved by the FDA.

Again more anti-vaxxer lies/exagerations/misrepresentations.

The AZ vaccine has completed the required trials and is approved for use in Canada.

There is no requirement for FDA approval.
There is no "peer review" at all. I honestly think you don't know the meaning of the words you use.
Do you even know what "peer review" means?

 

[Eclectic12]

With the talk of requiring FDA approval, maybe sags is telegraphing a move to the US?


Cheers

 

[Eclectic12]

As for "peer review", having published the study and/or having it indpendently reviewed certainly gives more confidence.
At the end of the day, the FDA or Health Canada or whatever the regulatory group in play does their own review that is going to count more for the decision being made.

IOW, it's not a requirement.


Cheers

 

[MrMatt]

As for "peer review", having published the study and/or having it indpendently reviewed certainly gives more confidence.
At the end of the day, the FDA or Health Canada or whatever the regulatory group in play does their own review that is going to count more for the decision being made.

IOW, it's not a requirement.


Cheers

I know what a peer review is, my point is that sags just vomits out words without knowing what they mean.

I know it's not a requirement, it isn't even normal for clinical approval trials. The reviewer is the agency that grants approval, and they are not a "peer".

I just want to make it abudantly clear to as many as possible, that they should be very skeptical of anything antivaxxers like sags are claiming. It should be obvious that they don't know what they're talking about.

 

[sags]

You don't have a clue.

The FDA relies on advisors from the CDC and experts from all over the world.

Who do you think does the analysis.........a bunch of computer geeks in the FDA office ?

 

[MrMatt]

You don't have a clue.

The FDA relies on advisors from the CDC and experts from all over the world.

Who do you think does the analysis.........a bunch of computer geeks in the FDA office ?

What don't I have a clue about?
I know that the FDA, CDC, and actually all the global organizations work together.
Who does the analysis? the reviewers.

My point was much simpler.
You said the clinical trials were not concluded.
I pointed out that the required clinical trials have been completed and the AZ vaccine is approved.

You falsely claimed FDA approval is required. This is not true. It simply isn't, and you have refused to provide any support that such an approval is required.
Canada has approved the AZ vaccine, and there is no requirement that we wait for the approval of a foreign agency to approve this (or any) vaccine.

You are making false statements, you are actively spreading COVID19 disinformation.

The AZ vaccine is approved for use in Canada.

 

[sags]

The FDA has to approve the clinical trials throughout the multi-levels and conclusion.

The clinical trials continue after FDA approval and under their direction to study side effects and efficacy.

Canada didn't conduct any AZ clinical trials. We have relied on the clinical trials and approvals in other countries.

The Canadian regulator says it is monitoring the US trials and certainly will be interested in FDA approval.

 

[MrMatt]

The FDA has to approve the clinical trials throughout the multi-levels and conclusion.

Canada didn't conduct any clinical trials. We have relied on the clinical trials and approvals in other countries.

The Canadian regulator says it is monitoring the US trials and certainly will be interested in FDA approval.

You just keep doubling down.
FDA approval is not required.
We all know this, yet you keep saying that the FDA has to approve it.
I'd actually prefer they hold off approving it for as long as possible.

Canada has approved the AZ vaccine, the trials required for that approval have been completed.
This is the approval that matters for Canadian use.

https://www.cbc.ca/news/politics/astrazeneca-approved-1.5929050

Of course they're monitoring the US trials, they should be monitoring everything.

 

[cainvest]

The AstraZeneca US clinical trial, however, occurred during the worst phase of the pandemic as shown below. It also included participants in Latin American countries, so the numbers can't be compared directly to Pfizer's trial.

Timing obviously does play a role ...

So far, studies suggest that the vaccines currently in use can recognize the emerging variants — but they don’t provide as much protection against these new strains. The variant from South Africa, for example, reduced Pfizer-BioNTech’s antibody protection by two-thirds, according to a February study. Moderna’s neutralizing antibodies dropped six-fold with the South Africa variant.

As pointed out in the video, any vaccine that eliminates severe outcomes (both short and long term) should be considered a worthwhile vaccine to get.

 

[Eclectic12]

... The FDA relies on advisors from the CDC and experts from all over the world.
Who do you think does the analysis.........a bunch of computer geeks in the FDA office ?
... The FDA has to approve the clinical trials throughout the multi-levels and conclusion ...

This makes no sense to me .... why would the FDA relay on people outside the US to review data from a clinical trial for AZ being run in the US?
It makes it sound like you think the FDA has outsourced it's evaluation parts of the approval process.

Not to mention that there are past examples where other countries approved a drug and the FDA refused to approve it as they didn't like the data or lack of it from other countries.

... Canada didn't conduct any AZ clinical trials. We have relied on the clinical trials and approvals in other countries.

And that's any different than the FDA saying they will accept foreign clinical study results as part of the application for approval in the US?

... The Canadian regulator says it is monitoring the US trials and certainly will be interested in FDA approval.

It gives more confidence when multiple countries review the clinical studies held in multiple countries all agree the benefits outweigh the risk. It does not stop individual countries from coming to different conclusions for approval/not approved ... as has happened in the past.


Cheers

 

[Eclectic12]

You just keep doubling down.
FDA approval is not required.
We all know this, yet you keep saying that the FDA has to approve it ..

It seems like this version has all other gov't health agencies as a subsidiary of the FDA!!

That's despite the FDA being the odd agency out with many others having granted approval, which has happened in the past.


Cheers

 

[james4beach]

Again more anti-vaxxer lies/exagerations/misrepresentations.

sags is correct that the AZ clinical trial result has not yet been published or peer reviewed.

But what you say is also correct, that FDA approval is not required to use the vaccine in Canada.

 

[ian]

Does it matter? Do people have a choice? Just take what you can get and be thankful for it.