Monday, 25 January 2021

Moderna admits South African COVID variant reduces its vaccine antibody levels SIX-FOLD as it works on 'booster' to make shot more 'effective'

 Moderna's coronavirus vaccine is six times less effective against the South African variant, the firm admitted on Monday. 

It is now working on a tweaked version of its booster shot that would specifically target the South African variant. 

However, the current shot is still 'protective' against variants from both the UK and South Africa - but that protection may fade faster against the South African form. 

Dr Anthony Fauci said last week that South Africa's variant is the most concerning one that has emerged because it may render vaccines less effective and has already spread to at least 20 other countries.     

And President Biden banned travelers arriving from South Africa as of Monday, adding the nation to the 'restricted list' alongside the UK, Ireland, Brazil and 26 countries in Europe. 

Lab tests of its coronavirus vaccine against new variants from the UK and South Africa showed that the shot is still protective against both. But its potency is reduced by six-fold against the South African variant - so the firm is testing a booster shot developed specifically to fight the evasive variant (pictured: Moderna scientists work on COVID-19 vaccines in the lab)

Lab tests of its coronavirus vaccine against new variants from the UK and South Africa showed that the shot is still protective against both. But its potency is reduced by six-fold against the South African variant - so the firm is testing a booster shot developed specifically to fight the evasive variant (pictured: Moderna scientists work on COVID-19 vaccines in the lab) 

'We are adding South Africa to the restricted list because of the concerning variant present that has already spread beyond South Africa,' said Dr Anne Schuchat, the CDC’s principal deputy director, in a Reuters interview Sunday.  

It comes after former President Trump lifted travel restrictions, only to have them reinstated by the new administration in an eleventh hour bid to prevent the importation of new variant. 

So far, no cases of the South African variant have been reported in the US, but even Dr Fauci admitted that it could easily go undetected because the US has done poor surveillance for new variants. 

'Thus far, it does not appear at all that the South African strain is in the US,' Dr Fauci said during a White House press briefing last Thursday. 

'That said, the level of sequence surveillance is not at the level we would like it to be, but given the information we have today, it doesn't appear that it's here.'


On Monday, he also admitted that the UK variant may be more deadly than older forms, and that the South African one could mean vaccines need to be tweaked. 

Fauci on Monday also said the US might need to 'upgrade' its vaccines to work against the South African variant - but then insisted the vaccines are still effective against it and that it only makes them less effective by a 'very slight' amount. 

Moderna's vaccine is more than 94 percent effective against the older 'wild-type' coronavirus variants that account for most US cases. 

The firm's new research put the vaccine to the test against new variants by combining the blood plasma of someone who had been vaccinated with samples of the new virus variants in the lab. 

Against the UK variant, they saw 'no significant impact' on the levels of neutralizing antibodies that bind to the virus and block it from infecting human cells. 

That's both promising and expected. 

The UK variant is thought to be about 70 percent more infectious than older forms, but has shown few signs that it would render vaccines less effective.   

However, UK scientists announced Friday they believe it may be 30 to 40 percent more deadly than other forms.   

Already the UK variant has spread to 60 countries, including the US, where there are at least 159 cases in 22 states.  

 Just 24 hours before the UK officials' alarming announcement, Dr Fauci had assured Americans the UK variant was not more deadly. 

But as of Monday, he has changed his tune. 

'The data has not come out officially but taking a look at the preliminary data that the UK scientists have analyzed, I'm pretty convinced that there is a degree of increase in seriousness of the actual infection which we really have to keep an eye on,' he told Today.   

If vaccines are equally effective against it, this concern will soon ebb, though. 

That's why Dr Fauci remains more worried about South Africa's variant - and Moderna's disturbing data only deepens concerns. 

'We are more concerned about the South African strain right now. When you do studies in the test tube, in vitro studies, it shows that the ability of monoclonal antibodies that have been used as therapies, that is really impaired in the presence of these particular variants.

'They don't work as well as treatment. There is a very slight , modest diminution in the efficacy of a vaccine against it but there's enough cushion with the vaccines that we have that we still consider them to be effective against both the UK strain and the South African strain. 

So far, at least 77 cases of the South African variant have been found in the UK and it has spread to at least 20 countries. 

It has not been detected in the US, but former FDA Commissioner Dr Scott Gottlieb said Monday it has likely already arrived.  

Brazil's variant has been detected in Japan, Germany and France, but has not been found in the UK or the US.  


While there was a six-fold reduction in neutralising antibodies produced against the South African variant, the levels remained above those that are expected to be protective, Moderna said.

Stephane Bancel, chief executive officer of Moderna, said: 'As we seek to defeat the Covid-19 virus, which has created a worldwide pandemic, we believe it is imperative to be proactive as the virus evolves.

'We are encouraged by these new data, which reinforce our confidence that the Moderna Covid-19 vaccine should be protective against these newly-detected variants.'

The UK Government has purchased 17 million doses of the Moderna vaccine – enough to vaccinate 8.5 million people, but the first doses are not expected to arrive in the country until the spring.

The biotech company is also launching a clinical trial to test an additional booster dose of its vaccine (mRNA-1273) to study the ability to further increase antibodies against emerging strains beyond the existing primary vaccination series.

The company is also advancing an emerging variant booster candidate (mRNA-1273.351) against the variant first identified in South Africa.


Mr Bancel added: 'Out of an abundance of caution and leveraging the flexibility of our mRNA platform, we are advancing an emerging variant booster candidate against the variant first identified in the Republic of South Africa into the clinic to determine if it will be more effective to boost titers (antibodies) against this and potentially future variants.'

It is unclear whether the firm is developing similar booster candidates for the variant that emerged in Brazil - and has a similar profile to South Africa's - or any others, including the four homegrown variants discovered by US scientists.  

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