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Brazil Rejects the Gamaleya Vaccine

blogs.sciencemag.org

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Re: Brazil Rejects the Gamaleya Vaccine

#101

Post by rbanffy »

randomsquared wrote: post #74
rbanffy wrote: post #72

Earlier quoted context omitted.

It’s being said they didn’t actually test it.

"Being said"... Let me guess, Sputnik News? https://www.ndtv.com/world-news/scientists-back-brazil-over-... > According to a slideshow uploaded online, scientists at Anvisa, Brazil's regulator, said they *tested* samples of the booster shot and found it was "replication competent" -- meaning that once inside the body, the adenovirus can continue to multiply.

No.

https://www.google.ie/amp/s/super.abril.com.br/blog/bruno-ga...

“Nível de RCAs, principal argumento usado para vetar o imunizante russo, não foi medido pela agência - que afirma ter se baseado em documento do próprio Instituto Gamaleya”

Re: Brazil Rejects the Gamaleya Vaccine

#102

Post by ArgyleSound »

gnfargbl wrote: post #92
pixelkritzel wrote: post #30

Virologist Dr. Angela Rasmussen about the ability of the vector virus to replicate https://mobile.twitter.com/angie_rasmussen/status/1387397186...

In the linked Twitter thread, Dr Rasmussen says that a consequence of the Ad5 vector becoming replication competent is that the E1 gene might have replaced the spike protein, rendering the vaccine ineffective. Are there any other consequences to the Ad5 vector virus being able to replicate? Is the virus harmful to humans in any way, or does it have the potential to become harmful?

Typically Ad5 causes upper respiratory tract infections which may manifest as a cold if you’re lucky or lead to pneumonia if you’re not, although things like conjunctivitis and gastroenteritis are not unheard of. Obviously we don’t know how applicable this knowledge is to the Sputnik Ad5.

Re: Brazil Rejects the Gamaleya Vaccine

#103

Post by ummonk »

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.

Weren’t the first viral vector vaccines (for Ebola virus) only recently approved?

As to track record, the first viral vector vaccines in widespread use (i.e. the COVID vaccines) will have killed hundreds (possibly even thousands) of people via blood clots. That’s a worthwhile trade off for a disease as deadly as COVID. But it would be less acceptable against less dangerous diseases, particularly if safer vaccine technologies are available.

Re: Brazil Rejects the Gamaleya Vaccine

#104

Post by sam_lowry_ »

petre wrote: post #88
Clewza313 wrote: post #71

Earlier quoted context omitted.

I'm not sure what you're even trying to say here. Whoever wrote that response is quite clearly authorized speak on behalf of Gamaleya and the Sputnik V vaccine team, and while I'm sure there are plenty of conscientious scientists at Gamaleya, as Derek says this really is the worst possible public response. Tackle the problem seriously, sort out the manufacturing process, and the world will have one more weapon in the…

It's the post-Soviet Russian way of doing things, comrade. First claim fake news, then quietly fix the vaccine and deny accountability. Some vaccine scientists are due to accidentally fall off their apratment windows while doing Easter cleaning, with a helping hand from the FSB.

As laughable as it sounds, this is the sad truth.

Re: Brazil Rejects the Gamaleya Vaccine

#105

Post by weinzierl »

fsh wrote: post #100
weinzierl wrote: post #97

I'm a complete layman but reading about the replication prevention I wonder: Could it be that they left E1 intact deliberately? I suppose (naively) that a virus that replicates should cause a stronger immune system response and therefore increase efficacy. Being an adenovirus the worst thing that could happen is that you get a common cold. Common cold once vs potential death is not the worst trade-off imaginable, if…

This is addressed in the article: Now, there have been debates over the years about whether you’d get a more effective vaccine that way, with a “replication-competent” adenovirus, but generally it’s believed that you can do fine with the “replication-incompetent” ones, which let you *not* give your patients a new viral infection at the same time.

Thanks, that takes away the premise of my question.

Re: Brazil Rejects the Gamaleya Vaccine

#106

Post by weinzierl »

sanxiyn wrote: post #99
weinzierl wrote: post #97

I'm a complete layman but reading about the replication prevention I wonder: Could it be that they left E1 intact deliberately? I suppose (naively) that a virus that replicates should cause a stronger immune system response and therefore increase efficacy. Being an adenovirus the worst thing that could happen is that you get a common cold. Common cold once vs potential death is not the worst trade-off imaginable, if…

Gamaleya themselves says they removed E1. There is no reason to doubt it.

Thanks, that makes sense.

Re: Brazil Rejects the Gamaleya Vaccine

#107

Post by d1sxeyes »

weinzierl wrote: post #97

I'm a complete layman but reading about the replication prevention I wonder: Could it be that they left E1 intact deliberately? I suppose (naively) that a virus that replicates should cause a stronger immune system response and therefore increase efficacy. Being an adenovirus the worst thing that could happen is that you get a common cold. Common cold once vs potential death is not the worst trade-off imaginable, if…

Also, would this be transmissible? Could vaccinated person A infect unvaccinated person B, leading to community transmission of immunity?

I'm not an expert in this field, but it sounds logical at least, and provides a motive for the discrepancy.

Re: Brazil Rejects the Gamaleya Vaccine

#108

Post by nottorp »

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…

> My intuition, given the absolute (small) magnitude of blood clots, is that it’s not a huge issue.

Except there are two other vaccines with no risk of bloot clots. So if you can choose, why not choose the ones that aren't linked to that?

Ofc, that mostly goes for the US and EU who have secured supply.

Re: Brazil Rejects the Gamaleya Vaccine

#109

Post by gus_massa »

ummonk wrote: post #103
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.

Weren’t the first viral vector vaccines (for Ebola virus) only recently approved? As to track record, the first viral vector vaccines in widespread use (i.e. the COVID vaccines) will have killed hundreds (possibly even thousands) of people via blood clots. That’s a worthwhile trade off for a disease as deadly as COVID. But it would be less acceptable against less dangerous diseases, particularly if safer vaccine tech…

The MMR vaccine contains "live" weakened virus. The kid sometimes get some small red points in the skin that disappear in a few days.

The oral polio vaccine "Sabin" has "live" virus. It's stronger than the injectable polio vaccine, but there is a small risk that the virus can escape and mutate and after a year or so cause polio to another person. So countries without polio cases, only use the injectable version "Salk" that does not contain "live" virus.

The first smallpox vaccine was just a similar virus for cows. The latest smallpox vaccine also used a "live" virus.

Re: Brazil Rejects the Gamaleya Vaccine

#110

Post by zgcarvalho »

I would like to add information that I believe is very relevant.

During the pandemic, the congress approved a law (Article 16, Law No. 14.124/2021)[1] that defines a limit period of 30 days for Anvisa to approve or disapprove the vaccine. If, after 30 days, Anvisa does not issue its final recommendation, the vaccine is automatically approved. I think this law is absurdly stupid, but let's get back to the facts.

Days before denying Sputinik's authorization to use, Anvisa asked the Federal Supreme Court (STF) to suspend the 30-day period alleging that the data received were incomplete and information was missing.

A supreme court judge denied, on March 26th, the suspension of the deadline saying that this possibility was not manifested in the law. And he added that Anvisa's decision must be technically based, "not admitting the mere allegation of insufficient documentation or the simple allusion to potential risks". And if Anvisa does not decide on import and distribution authorization requests within 30 days, the interested parts are automatically authorized to import and distribute Sputnik V [2].

One day after the judge denied the suspension of the term and one day before the deadline, Anvisa denied the request.

[1] https://www.in.gov.br/en/web/dou/-/lei-n-14.124-de-10-de-mar... [pt]

[2] https://agenciabrasil.ebc.com.br/saude/noticia/2021-04/lewan... [pt]

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