São Paulo CoV vaccination

[Riobard]

São Paulo state may get the jump on vaccination.

CoronaVac, launched by Sinovac in China, shows 78% efficacy for its Phase 3 trial results thus far in São Paulo and will likely be approved for emergency authorization. Moderate to severe infection was nil for the vaccination arm, with mild cases where breakthrough infection occurred. 

In the real world, it could be that minimally 1 in 4 vaccinated can catch and transmit CoV. 

Only the data for Brazil will be the basis of seeking the green light from Anvisa, although research findings were more promising in Turkey but for interim data for a trial one-tenth the size of São Paulo’s and analysis for only 29 cases of infection. There were 200 or so cases among São Paulo study volunteers, most or all health care workers.

2 shots, at least 85 million individual doses for the state, production will take some time, other parts of Brazil did not enter into any contract with Sinovac. Ongoing tension between Bolsonaro and Gov Doria.

Edited January 7, 2021 by Riobard
Corrections

[Riobard]

The figures in more detail below. My mistake ... São Paulo was among a number of states with study locations.

A lot of doses may be available for distribution before the inventory of syringes necessary to administer the vaccine can be acquired. 

Edited January 7, 2021 by Riobard

[Riobard]

Apparently some of the political conflict has been put aside and the Brazil federal government has now just contracted for 100,000 doses of CoronaVac vaccine. I believe São Paulo will be a manufacturing hub. 

[Riobard]

The feds have also applied for authorization for the AstraZeneca vaccine. 

[scott456]

I want to get the better vaccine: Pfizer or Merdena.

[Riobard]

 

On 1/9/2021 at 4:03 PM, scott456 said:

I want to get the better vaccine: Pfizer or Merdena.

Neither will likely launch in hot Latin American counties due to cold chain requirements. 

Since both are messenger ribonucleic acid formats with similar study efficacy (translating to real world effectiveness) I don’t see much difference. Contrary to what is being considered in some places, I personally would not want a mix-and-match of the 2 doses, unless backed to the wall over a delay of inventory for the follow-up booster dose. I would want both injections of the Pfizer or of the Moderna rather than a substitution of one for the other.

For comparison, the more relevant question is one vaccine model against another vaccine model. Not so much the candidates within the approximately half a dozen models or types being investigated.

If you are not in a priority group for vaccination, for example, I am a senior but not likely to be offered government-issued vaccination until this Fall or later, there will likely be more products on the table than the Pfizer or Moderna. 

[Riobard]

Oh, the plot thickens and it’s a fucking mess in Brazil. The data for CoronaVac were reviewed and submitted to Anvisa, with a corrected efficacy of 50%, that is, 2:1 infection ratio placebo:vaccine.

However, I calculated the infection incidence against the backdrop of epidemiological data of new cases over the exact same dates. The infection rate over the 4 months of the study for the vaccinated group is 2.0%, no better than the general population proportion that were reported to be new cases over the same time period ... 1.9% !!!

Edited January 12, 2021 by Riobard
Corrections

[Riobard]

For comparison, other recent vaccine arms in research showed much lower breakthrough CoV infection over similar study duration compared to the 2.0% rate for CoronaVac:

Pfizer/BioNTech .044%

Moderna             .036%

AstraZeneca        .52%

Additionally, even if the CoronaVac data submitted by Butantan to Anvisa are to be believed, the 50.4% efficacy, coincidentally the metric just placed at the threshold for consideration for approval [hmmmm], would nevertheless have a 95% confidence interval whose lower bracket would be well below 50%. 

[Riobard]

Unfortunately, the standard of releasing to the public domain the detailed briefing of study results, such as what Pfizer and Moderna did leading up to FDA review, is not apparently done in Brazil.

We need to see Brazil’s Butantan Institute and the CoronaVac research sponsor, China -based Sinovac, transparently revealing the exact infection numerators and subsample denominators to yield efficacy metrics.

It is more and more apparent that they are mining the data and stratifying disease severity in such a way as to spin the data in the best possible light. When researchers try to quickly analyze results with an agenda, mistakes are made in the manipulation. There have already been glaring errors and this has naturally resulted in distrust by the public that is already quite pronounced. 

Butantan had initially focused on the vaccine trial results suggesting a prevention of severe COVID cases. When pressed to equivalize the analysis with the conventional inclusion of all bona fide cases of infection, they seem to be scrambling to reach and exceed the 50% efficacy standard to no less than 50.1%, thinking that the crisis of community infection rates will help put the application ‘in the bag’, hoping that the reality of poor vaccine performance overall doing little to stem the tide of transmission will be overlooked.

Sinovac is also pushing to jab the deltoids of Turks and Indonesians with CoronaVac based on their large sample Brazilian study results along with efficacy data that appear promising in those two countries but that have very small sample sizes reducing statistical analytical power. 

Edited January 13, 2021 by Riobard

[Riobard]

I forgot to also mention that the CoronaVac researchers removed 26% of the overall study sample to report the comprehensive analysis of 50% efficacy that they think Anvisa would be foolish to reject.

Quelle horseshit. Why would they think nobody would notice. It is easy to track these inconsistencies as media releases roll out.

Red flags all round. 

[Riobard]

I want to try to be fair and unbiased in my critique. As an afterthought, it may be that the infection rates among all study participants exceeded national general population background figures because the study cohort would have been followed systematically ... less missed diagnoses.

The trial results generally suggest that individuals vaccinated with CoronaVac have reduced infection probability to about one-third relative to the case incidence norm. In contrast, Pfizer and Moderna reduce probability to between one-tenth and one-twentieth of non-vaccination.

The 95% probability of CoronaVac efficacy (confidence interval bounds) is about 35% to 62%. The lower interval bounds of other approved vaccines is much higher than the upper bound for CoronaVac. 

The Butantan presenter indicated a theoretical projection, based on an ascertainment correction for the typical rate of undetected cases, that about 12% people of those vaccinated with CoronaVac would be expected in absolute terms to nevertheless acquire SARS-CoV-2. 
——-

And now I am off in the cold for a blood draw three days following my first dose of experimental vaccine (or placebo). 

Edited January 14, 2021 by Riobard

[Riobard]

As Anvisa meets this weekend to begin to decide the near-term fate of the vaccines CoronaVac and Covishield, the state of Amazonas is in crisis with an apparent very worrisome coronavirus variant that may be more infectious and may have mutations that ‘escape’ previous natural immunity as well as current vaccine candidates.

As patients from Manaus are desperately transferred to other regions due to lack of ICU & oxygen capacity, with gravediggers on alert for an upswing of tasking, the new variant might be expected to spread nationally. 

I don’t know how up to speed the genetic sequencing is. Britain has shut down travel from South America, including Brazilian transit through Portugal. There seem to be actually two variants of concern out of Brazil. One might expect travellers/visitors that are In Brazil, or their flights, to be restricted from returning to their countries of origin in spite of negative PCR tests. If a variant in Brazil is truly a superbug, the rest of the world will want to fortify boundaries.

Edited January 15, 2021 by Riobard
Correction

[Riobard]

Non-Bolsominions’ pots’n’pans ... 

[Riobard]

Today, Anvisa adjudicated the applications submitted for both the CoronaVac and Covishield vaccines, authorizing both products for emergency use.

Regarding CoronaVac, studied there in a large scale research trial, there was a lot of political pressure to roll out something quickly as better than nothing ... it may offset 1 case of every 3 cases that would have otherwise occurred. 

Personally, I would favour AstraZeneca’s Covishield that will eventually transport in from Serum production facilities in India. I think that it will also be more likely to be diligently tweaked for efficacy wrt the growing array of coronavirus variants. 

Edited January 17, 2021 by Riobard

[wncdemcub]

If Gov Doria can get Sao Paulo state vaccinated quicker than others in Brazil...it may be his ticket to beating Bolsonaro in the 2022 elections.

[Riobard]

34 minutes ago, wncdemcub said:

If Gov Doria can get Sao Paulo state vaccinated quicker than others in Brazil...it may be his ticket to beating Bolsonaro in the 2022 elections.

Too soon.

It would mean he is hoarding preferentially, and there are 25 other states with ballot boxes. The fed courts may order equitable CoronaVac distribution. The public has thrown off most of its contrarian vaccine hesitancy. Funny what headlines of infected suffocating people drowning above the water table does. 

Whoever can facilitate a supply of desperately needed oxygen, for example in a state with ironically the highest atmospheric O2 globally, may see an upswing in popularity. 

If São Paulo structural pandemic mitigation is relaxed by two-thirds as folks get cocky, and with state border permeability, the net yield of a vaccine such as CoronaVac where  the odds of infection relative to pre-vaxx baseline are reduced only to one-third, all in the context of escalating case reproduction numbers, might not be very pronounced.

And the aggressive mutation strain that is evident in Amazonas, with a 1.6+ per/person reproduction ... 10-fold case numbers within 5 transmission cycles ... is bound to creep across all regions. 

Not a good time to be a politician there, let alone a brasileiro.