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Brazil Rejects the Gamaleya Vaccine

blogs.sciencemag.org

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Re: Brazil Rejects the Gamaleya Vaccine

#61

Post by sudosysgen »

sanxiyn wrote: post #50
sudosysgen wrote: post #34

Earlier quoted context omitted.

The vaccines delivered to Brazil also have a replication deficient Ad5 vector, Anvisa says that among the vast majority of replication deficient vectors some replication-able viruses were present. There is pretty much no chance at all that this affects efficacy.

> Anvisa says that among the vast majority of replication deficient vectors some replication-able viruses were present. Do you have the source for this claim? Linked Anvisa slides page 6 says "todos os lotes" (all lots) had replicating virus. I agree this is about quality control and it is extremely unlikely to affect vaccine efficacy. (If anything, it would improve vaccine efficacy.)

I will try to find the source again, however I would read todos os lotes as saying that there are detectable replicant viruses.

Replicant viruses do not carry the spike protein, they don't contribute to antigen protection.

Re: Brazil Rejects the Gamaleya Vaccine

#62

Post by Exmoor »

exmadscientist wrote: post #42

If the vector is replicating, does that explain some piece of why Sputnik V is significantly more effective than the other adenovirus vector vaccines? (If that's even true, of course, since it may well not be!) Or is it simply a more effective preparation of a vaccine, due to things like the Ad5/Ad26 combination?

Unlikely, because the part of the adenovirus they delete that allows it to replicate is what they replace with the portion that generates the spike protein antigen. So if some of the adenovirus is replicating it's inherently not doing what you want it to do to produce an immune response.

Re: Brazil Rejects the Gamaleya Vaccine

#63

Post by Exmoor »

627467 wrote: post #24
ummonk wrote: post #12

Earlier quoted context omitted.

Intuitively speaking, using a viral vector has inherent risks that aren’t present with mRNA or protein subunit vaccines. To the extent that the latter technologies prove effective for vaccines against various viruses, I would think viral vectors should not be a preferred technology going forward for vaccine development.

Intuitively, the risks of viral vector vaccines are well known because they have been used for at least a decade while mRNA are being used in large scale for the first time only now.

Perhaps previously, but at this point hundreds of millions of people have been injected with mRNA vaccines and the safety profile and efficacy seem much better than any other vaccine technology.

Re: Brazil Rejects the Gamaleya Vaccine

#64

Post by Exmoor »

perardi wrote: post #43
hardtke wrote: post #2

I wonder how much we are seeing general problems with adenovirus vector vaccines (e.g. blood clotting and this manufacturing issue) only because we've never rolled a vaccine out to a large population so quickly. Regulatory agencies are likely afraid to approve any at this point, which does not bode well for other vaccines using the same technology.

My intuition, given the absolute (small) magnitude of blood clots, is that it’s not a huge issue. Except that it is , because it has people spooked. Humans, myself included, are just terrible at gauging relative risk, and it doesn’t really matter that you are way more likely to die in your car driving to get the vaccine than from any vaccine complication. You are putting this in your arm, and people find it scary whe…

It's not considering the disease it's protecting against and the currently likelihood of getting it, but if we were talking a flu shot or a vaccine for some much less common disease that math would change.

Re: Brazil Rejects the Gamaleya Vaccine

#65

Post by wbl »

sudosysgen wrote: post #58
wbl wrote: post #49

Earlier quoted context omitted.

You don't know that this is the same vaccine as what was injected before.

Why is there any reason to think it wasn't? Replicant viruses are very easily explained by a QA failure, and Brazil doesn't claim that non-replicant viruses aren't there anymore.

That QA failure means the vaccine injected is different: they tested without reproduction competent in the trials. What else could they have missed along with this?

Re: Brazil Rejects the Gamaleya Vaccine

#66

Post by randomsquared »

SpaceRaccoon wrote: post #11

A reminder that "U.S. officials pushed Brazil to reject Russia’s coronavirus vaccine" [0] for political reasons. > Under a section titled “Combating malign influences in the Americas,” the HHS report states that countries including Russia “are working to increase their influence in the region to the detriment of US safety and security.” The global affairs office coordinated with other U.S. government agencies “to dis…

This is not mutually exclusive with the findings of the Brazilian investigators. More than likely this will spur other investigations which should find the same thing if the Brazilian investigators were correct.

Re: Brazil Rejects the Gamaleya Vaccine

#67

Post by randomsquared »

marcodiego wrote: post #41

Covid19 has been extremely politicized in Brazil. President's supporters were mostly against vaccine until coronvac (sinovac vaccines) was approved by anvisa, Brazil's equivalent to FDA. In Brazil this pandemic took ridiculous proportions. In the beginning, it was said that it wouldn't kill even 800 people[0]. It was said that it would be no more than a little flu and that children should not skip schools[1]. After t…

That is not mutually exclusive to investigators finding problems with Sputnik V.

Re: Brazil Rejects the Gamaleya Vaccine

#68

Post by riffraff »

Exmoor wrote: post #63
627467 wrote: post #24

Earlier quoted context omitted.

Intuitively, the risks of viral vector vaccines are well known because they have been used for at least a decade while mRNA are being used in large scale for the first time only now.

Perhaps previously, but at this point hundreds of millions of people have been injected with mRNA vaccines and the safety profile and efficacy seem much better than any other vaccine technology.

But we haven't seen long term effects of mRNA vaccines.

I am not expecting a "children of men" distopy, and I'd rather have an mRNA vaccine than any other, but it is possible there might be some unexpected issues in the long run.

Re: Brazil Rejects the Gamaleya Vaccine

#69

Post by marcodiego »

randomsquared wrote: post #67
marcodiego wrote: post #41

Covid19 has been extremely politicized in Brazil. President's supporters were mostly against vaccine until coronvac (sinovac vaccines) was approved by anvisa, Brazil's equivalent to FDA. In Brazil this pandemic took ridiculous proportions. In the beginning, it was said that it wouldn't kill even 800 people[0]. It was said that it would be no more than a little flu and that children should not skip schools[1]. After t…

That is not mutually exclusive to investigators finding problems with Sputnik V.

And...?

Re: Brazil Rejects the Gamaleya Vaccine

#70

Post by rbanffy »

marcosdumay wrote: post #48
major505 wrote: post #22

Earlier quoted context omitted.

To me Gamaleya is turning a thecnical decision in a political one. Thanks to mistakes and possible crimes commit by the Brazilian goverment, when rejecting other vacines, they are now being pressured in accepting this vaccine no matter what. I don't think this is how a sanitary inspection agency should act, approving things based in pure pressure.

> Thanks to mistakes and possible crimes commit by the Brazilian goverment, when rejecting other vacines Well, that's the first COVID-19 vaccine the Brazilian government has rejected.

Bolsonaro actively campaigned against the vaccine that is responsible for about 98% of the doses administered to Brazilians because it was seen as sponsored by a political adversary.
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