Biden gettin 'er done

New evidence that the P.1 escapes vaccines (a small - but well done - study using plasma from 8 individuals vaccinated with the CoronaVac, and like I said - and the authors also highlight - there is still cellular immunity). Still not peer-reviewed, submitted to The Lancet.

https://static.poder360.com.br/2021...riante-manaus-coronavac-lancet-1-mar-2021.pdf

"Here, we described a loss of neutralization capacity of at least 6-fold in plasma from COVID-19 convalescent patients against isolates of P.1"
"these results suggest that P.1 virus might escape from neutralizing antibodies induced by an inactivated 304 SARS-CoV-2 vaccine (i.e., CoronaVac)"
"Moreover, five months after booster immunization with CoronaVac, plasma from vaccinated individuals failed to efficiently neutralize P.1 lineage isolates."

They used both convalescent plasma, and plasma from vaccinated individuals. Observe that five months might be pushing the limit of response. Still, a 6-fold antibody drop exceeds the 4-fold threshold usually utilized to indicate that a flu vaccine needs to be updated to new strains. It is becoming clearer that as expected, variants-updated boosters will be needed. Again, we are involved in a race vaccines vs. mutations.

This study does have limitations, the biggest one being that the neutralization was small for both the P.1 and the B (ancestral) variants and near the detection limit of the VNT50 assay used in the study (1:20). So, the P.1 fell below the threshold (<20) and the B hovered above it (25) but there was insufficient statistical power given the low number of samples (.

Also let's not forget that the CoronaVac has demonstrated weaker immunogenicity than the BNT162b2 (the Pfizer/BioNTech vaccine) so we can't assume that these lousy CoronaVac results indicate that the Pfizer will be just as lousy.

Still, limitations or not, I find these results concerning, especially because for now, in Brazil, all that they have is a limited quantity of CoronaVac and AstraZeneca (the latter has also demonstrated low efficacy against new strains). And they have a huge outbreak there. It doesn't bode well for their capacity to contain it, and we know that the more out of control an outbreak is, the more it generates mutations and even newer variants. Brazil has finally made a deal with Pfizer and they are making another one with Moderna, but deliveries will be months ahead since by now the production capacity of these companies is spoken for, to honor earlier contracts with other countries.

So I'm afraid that the Brazilian outbreak will come back to bite other countries.

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On another news, regulators from the UK, Australia, Canada, Singapore, and New Zealand have indicated that they will fast-track variants-updated boosters manufactured by the makers of currently approved vaccines, a smart move. To expedite the battle against the new variants, we need updated vaccines as soon as possible.

 

Excellent post. Agreed. Just an apart: there are not 2 but 4 approved Chinese vaccines, made by the companies Sinovac (CoronaVac), Sinopharm Beijing, Sinopharm Wuhan, and Cansino - and they have a fifth one still in development, made by Anhui Zhifei Longcom. To date there are 12 vaccines approved somewhere (approved in at least one country; most of them in multiple countries) and two more are imminent (Novavax, Curevac/GSK). There are countless others in various stages of development/testing. So, yes, there is competition for the international market, and no, these vaccine makers are not interested in holding back production to starve the market.

Another factor is that if they were to withhold production, they'd risk seeing their vaccines having no takers if the virus evolves too much and escapes them consistently. They'd need updated versions and would have to throw away the batches of the older vaccines. So, no, all companies are trying to produce as much as they can.

 

Thanks for the info. I struggle to keep up with what is happening in China.

I can't think of an event like this in the history of modern vaccines. Any company that can make a working vaccine is going to make money.