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The vaccine battle against variants is on as Omicron spreads

Omicron looks to be milder than that of the Delta variant, but the reduction in severity could be canceled out by the rate at which Omicron is spreading

The alarming way Omicron is spreading is giving impetus for pharma to find solutions for it The WRAIR team used a new vaccine technology called Self-assembling Protein Nanoparticle The US Food and Drug Administration recently authorized Merck's antiviral pill, molnupiravir

Omicron looks to be milder than that of the Delta variant, with those infected being 40% to 70% less likely to be admitted to hospital, according to recent studies.

But the reduction in severity could be canceled out by the rate at which Omicron is spreading, as the number of daily infections soared past 100,000 in the UK for the first time since the pandemic began.

Omicron is now the dominant version of the coronavirus in the US, accounting for 73% of new infections last week, federal health officials said.

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Image source: Statista.com

The Centers for Disease Control (CDC) numbers showed nearly a six-fold increase in Omicron’s share of infections in only 1 week.

The alarming way Omicron is spreading is giving impetus for pharma to find solutions for it. But one US government-led effort may have beat them all.

Variant killer

A novel vaccine against COVID-19 developed by the researchers at the Walter Reed Army Institute of Research (WRAIR), a US biomedical research facility led by the US Department of Defence, can not only evoke a good immune response but also protect against its variants as well as other COVID variants, a U.S. Army press release said. 

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Image source: Statista.com

Vaccine makers are racing against time to develop a variant-specific booster should previously administered vaccines fail against the mix of Omicron mutations.   

The WRAIR team used a new vaccine technology called Self-assembling Protein Nanoparticle, Business Insider elaborated. It consists of a small particle with multiple faces, each capable of carrying a part of a spike protein that the host’s immune system can latch onto and prepare against. Scientists attached spike proteins from multiple coronavirus strains on the Spike Ferritin Nanoparticle (SpFN) creating a pan-SARS vaccine candidate. 

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Results from WRAIR’s preclinical studies in non-human primates published in Science Translation Medicine showed that the SpFN when administered in two doses 28 days apart offered protection from the COVID-19 virus, its variants of concern such as Alpha, Beta, Gamma, and Delta variants as well as SARS-CoV-1 that caused an outbreak in 2002 and 2003, the press release said.

A new COVID vaccine pill

The US Food and Drug Administration recently authorized Merck’s antiviral pill, molnupiravir, “for the treatment of mild-to-moderate coronavirus disease (COVID-19) in adults with positive results of direct SARS-CoV-2 viral testing, and who are at high risk for progression to severe COVID-19, and for whom alternative COVID-19 treatment options authorized by the FDA are not accessible or clinically appropriate.”

This is the second Covid-19 antiviral pill authorized for ill people to take at home before they get sick enough to be hospitalized. Merck has an agreement with the US government for the company to supply 3.1 million courses of molnupiravir upon this authorization.

Data showed it cut the risk of hospitalization or death by 30% among high-risk adults and the treatment could work against the Omicron variant.

The FDA had also recently authorized Pfizer’s antiviral pill, Paxlovid, to treat COVID-19, the first antiviral pill authorized in the US for ill people to take at home before they get sick enough to be hospitalized.  

Paxlovid combines a new antiviral drug named nirmatrelvir and an older one called ritonavir and is administered as three pills given twice a day for five days.

Pfizer released updated results that showed the treatment cut the risk of hospitalization or death by 89% if given to high-risk adults within a few days of their first symptoms

In November, the Biden administration announced that it would purchase 10 million treatment courses for $5.3 billion.

The FDA emphasized in a statement that Paxlovid is not a substitute for vaccination in individuals for whom COVID-19 vaccination and a booster dose are recommended.

Understanding Omicron

Omicron is now confirmed in more than 20 countries but there is so little understanding of it.

Omicron’s success in southern Africa might be due largely to its capacity to infect people who recovered from COVID-19 caused by Delta and other variants, as well as those who’ve been vaccinated.  

Researchers want to measure Omicron’s ability to evade immune responses and the protection they offer.

Previous studies of Omicron’s spike mutations suggest that the variant will blunt the potency of neutralizing antibodies.  

If Omicron can dodge neutralizing antibodies, it does not mean that immune responses triggered by vaccination and prior infection will offer no protection against the variant. Immunity studies suggest that modest levels of neutralizing antibodies may protect people from severe forms of COVID-19, says Miles Davenport, an immunologist at the University of New South Wales in Sydney, Australia.

The threat of Omicron has prompted some rich countries, such as the UK, to accelerate and broaden the roll-out of COVID vaccine booster doses. But it’s not yet clear how effective these doses will be against this variant.

Third doses supercharge neutralizing-antibody levels, and it’s likely that this will provide a bulwark against Omicron’s ability to evade these antibodies.

More countries are detecting the Omicron variant, but the capacity to rapidly sequence viruses from positive COVID-19 tests is concentrated in wealthy countries, meaning that early data on Omicron’s spread will be skewed.