BioNTech/Pfizer vaccine is less potent against South African variant

[Mitz]

Covid-19 jab still works but produces only a third of the antibodies it did for original virus, study finds.

The BioNTech/Pfizer Covid-19 vaccine appears to be significantly less effective against the virus variant that emerged in South Africa, according to a study published on Wednesday.

The vaccine still works against the strain known as 501Y.V2, but the shot produced only a third of the antibodies that it did for the original virus in a lab study using an engineered virus.

The partners said there was “no clinical evidence” that people vaccinated with their Covid-19 shot lacked protection against the variant. It is hard to draw firm conclusions from lab experiments on how the vaccines will work on the variants in humans.

But they said they were making investments and talking to regulators so they could seek authorisation for an updated vaccine or a booster shot “once a strain that significantly reduces protection from the vaccine is identified”.

The vaccine from BioNTech/Pfizer was the first to receive emergency approval in many countries, including the US and the UK. The pair expect to make up to 2bn doses this year.

The paper, published in The New England Journal of Medicine, is based on experiments using the blood of 20 vaccine trial participants. The scientists from Pfizer, BioNTech and the University of Texas Medical Branch tested three different genetically engineered viruses, one with all the mutations of 501Y.V2, and two with subsets of the changes.

The scientists had previously found that the vaccine was likely to be effective against B.1.1.7, which first emerged in the UK.

But many other vaccine makers have found their shots are far less effective against the South African variant. South Africa halted the rollout of the Oxford/AstraZeneca vaccine after preliminary data showed it failed to protect against mild and moderate forms of Covid-19 caused by the new strain.

In clinical trials with sites in South Africa, both Johnson & Johnson and Novavax found their vaccines were less effective against the variant. In a lab study, Moderna found its vaccine only produced one-sixth of the antibodies in response to the 501Y.V2 variant than it did to the original virus.

Some vaccine makers, including Novavax and Moderna, are already preparing for clinical trials of a reformulated vaccine or a booster shot.

BioNTech/Pfizer’s vaccine — like Moderna’s — is based on messengerRNA technology that can be quickly adapted to new variants. The companies said they were evaluating the vaccine against other strains, including one that first emerged in Brazil, and were conducting studies to monitor the vaccine’s effectiveness outside of the laboratory.

https://amp.ft.com/content/2eb05859-54c1-45b5-9058-fa50fa6ca7da

 

[Vapaneezer Scrooge]

Bugger, that's the one I'm getting today, I doubt they will appreciate me doing a......

Still early days but hopefully all the vaccines will at least lessen the severity should you catch it.

 

[Mitz]

Same topic but from a different news source....

https://www.mlive.com/politics/2021...ork-against-new-variants-new-studies-say.html

Pfizer and Moderna vaccines work against new variants, new studies say

New reports suggest the Pfizer and Moderna vaccines for COVID-19 can protect people against new coronavirus variants, including one first seen in South Africa called B.1.351.

The reports were published Wednesday in the New England Journal of Medicine.

For the Pfizer vaccine, researchers at Pfizer and the University of Texas Medical Branch genetically engineered the virus to carry some of the mutations found in B.1.351 and tested them against blood samples taken from 15 people who had received two doses of the Pfizer vaccine.


While the blood serum samples produced less antibody activity, it was still enough to neutralize the virus, they wrote in a letter to the journal.

Separately, a team at the National Institutes of Health and Moderna published a letter in NEJM outlining details from an experiment that found a similar results: The Moderna vaccine produced an antibody response to the variants. In the case of the B.1.351 variant, the response was less robust but not enough of a reduction to make the vaccine work any less, researchers said.

“Despite this reduction, neutralizing titer levels with (the variant discovered in South Africa) remain above levels that are expected to be protective,” the company said in a statement.

With both the Pfizer and Moderna vaccines, no reduction in vaccine efficacy was found for the B.1.1.7 variant first seen in the U.K., researchers said.

However, many questions still exist around the degree to which the vaccines offer protection against the variants, Stephen Morrissey, the New England Journal of Medicine executive managing editor, said in a podcast posted Wednesday on the NEJM website.


While the current research shows that the vaccines can produce neutralizing antibodies against the variants, “they don’t actually inform us directly as to protection or medical activity, and we have to be careful about what we think the current level of protection is,” Morrissey said.

Both the Moderna and Pfizer research to date involving the variants involved testing blood samples to see if the vaccines produce antibodies. But it’s likely that immunity against COVID-19 also involves a cellular response, which the research hasn’t addressed so far.

Morrissey said there needs to be more “human studies to better define what protection means, and then how to optimize the vaccine.”

Morrissey noted reports involving people who previously had coronavirus and are now getting re-infected by a variant, suggesting that natural immunity has limitations against coronavirus.

“And some of those patients have developed severe disease, which is concerning,” he said.

No question, “there remain a huge number of unanswered questions,” said Jeremy J. Farrar, a British medical researcher, said in the podcast.


That includes the role of antibodies versus cellular responses in preventing coronavirus; how long vaccines can provide protection, and whether the vaccines impact transmission of the virus or simply prevent people from getting severely ill.

“There’s a lot more research that has to be done over the course of the next year of two,” Farrar said. “We need to get answers to these questions, as they will be critical questions for the long term.”