Moderna chief predicts existing vaccines will struggle with Omicron

The chief executive of Moderna has predicted that existing vaccines will be much less effective at tackling Omicron than earlier strains of coronavirus and warned it would take months before pharmaceutical companies could manufacture new variant-specific jabs at scale.

Stéphane Bancel said the high number of Omicron mutations on the spike protein, which the virus uses to infect human cells, and the rapid spread of the variant in South Africa suggested that the current crop of vaccines may need to be modified next year.

“There is no world, I think, where [the effectiveness] is the same level . . . we had with [the] Delta [variant],” Bancel told the Financial Times in an interview at the company’s headquarters in Cambridge, Massachusetts.

He added: “I think it’s going to be a material drop. I just don’t know how much because we need to wait for the data. But all the scientists I’ve talked to . . . are like, ‘This is not going to be good’.”

The Moderna chief executive’s comments come as public health experts and politicians have tried to strike a more upbeat tone about existing vaccines’ capacity to confer protection against Omicron.

On Monday, Scott Gottlieb, a director of Pfizer and former commissioner of the US Food and Drug Administration, told CNBC: “There’s a reasonable degree of confidence in vaccine circles that [with] at least three doses . . . the patient is going to have fairly good protection against this variant.”

Joe Biden, US president, subsequently said Omicron was “a cause for concern, not a cause for panic,” adding that the government’s medical experts “believe that the vaccines will continue to provide a degree of protection against severe disease”.

However, Bancel said scientists were worried because 32 of the 50 mutations in the Omicron variant are on the spike protein, which current vaccines focus on to boost the human body’s immune system to combat Covid.

Most experts thought such a highly mutated variant would not emerge for another year or two, Bancel added.

The Moderna chief’s predictions rattled investors in Europe and Asia on Tuesday, with equities and crude prices dropping. The European Stoxx 600 share index fell around 1.3 per cent with the UK’s FTSE 100, Germany’s Dax and France’s Cac 40 all down by around the same margin. Hong Kong’s Hang Seng index was 2.3 per cent lower.

Mansoor Mohi-uddin, chief economist at the Bank of Singapore, said that while investors were not pricing in a more serious disruption to the global economy from Omicron, it could take weeks for a clearer picture to emerge. “The view is still that it’s going to be a temporary hit, rather like [the Delta variant] turned out to be.”

Moderna and Pfizer have become the vaccine suppliers of choice for most of the developed world due to the high effectiveness of their jabs, which are based on messenger RNA (mRNA) technology.

In August, Moderna announced that people vaccinated with two doses of its jab “maintained antibodies through six months, including against variants of concern such as the Delta variant”.

But studies suggested that the company’s vaccine was less effective at preventing outbreaks of Delta than earlier strains of the virus.

A Stanford University study of a Delta outbreak at a California prison published last month found that Moderna’s jab was 56.6 per cent effective against infection — substantially lower than the level in studies conducted before the emergence of the variant, the researchers said.

Moderna and Pfizer are now working on new vaccines to target the Omicron variant, which the World Health Organization has said poses a “very high risk”.

Bancel said data indicating how existing vaccines performed against the Omicron variant, and whether it caused severe disease, should become available within two weeks.

But he said it would take several months before an Omicron-specific vaccine could be produced at scale, and suggested there might be a case for giving more potent boosters to the elderly or people with compromised immune systems in the meantime.

“[Moderna] and Pfizer cannot get a billion doses next week. The maths doesn’t work. But could we get the billion doses out by the summer? Sure,” said Bancel, who predicted Moderna could make a total of 2bn-3bn doses in 2022.

But he said it would be risky to shift Moderna’s entire production capacity to an Omicron-targeted jab at a time when other variants were still in circulation.

Bancel also hit out at critics who have accused vaccine makers of not doing enough to support rollouts in developing countries such as South Africa, where only a quarter of the population is fully inoculated, according to Johns Hopkins University.

“This was mostly a policy decision by the rich countries. In the US, we were told we had no choice but to give 60 per cent of our output to the US government. That was not a Moderna decision, that was a US government decision,” he said.

Bancel also said there was a surplus of jabs earmarked for Africa and that 70m Moderna vaccines were sitting in warehouses because Covax, an international body tasked with supplying low-income nations, or individual governments had not taken delivery of them.

“We are running out of space,” he said. “It’s because either they don’t have customs documents, or they don’t have fridge space, or because the ability to get doses in arms is a challenge.”

Additional reporting by Hudson Lockett in Hong Kong

Why vaccines are ‘not a silver bullet’

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New research examines the risk of household transmission of the Delta variant, despite vaccination. Christopher Furlong/Getty Images
  • The COVID-19 vaccine effectively prevents severe illness and death.
  • The Delta (B.1.617.2) variant of SARS-CoV-2 is spreading globally in populations with high vaccination rates.
  • 1 in 4 fully vaccinated people who have exposure to the Delta variant in the home are likely to get the infection.
  • The peak viral load of the Delta virus does not differ between fully vaccinated and nonvaccinated individuals.
  • The elimination of the Delta strain of the virus takes place more quickly in vaccinated individuals.

The SARS-CoV-2 Delta variant is the most widely spread variation of the virus, accounting for about 99.8{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809} of cases in the United Kingdom. The highly transmissible Delta variant is spreading globally, including in populations with high vaccination rates.

Several studies have shown the effectiveness of the COVID-19 vaccines in protecting from severe disease and death. Research has also confirmed that fully vaccinated individuals have a lower risk of infection with both the Alpha (B.1.1.7) and Delta variants compared with unvaccinated people.

However, to date, vaccination has not limited the spread of the Delta variant. A new study, which appears in The Lancet Infectious Diseases, has found that vaccination alone is not enough to stop the household transmission of the Delta variant.

Researchers from Imperial College London, the UK Health Security Agency, and the Manchester Foundation NHS Trust collaborated to carry out this “real life” study of household transmission in the U.K.

The researchers recruited 621 people over 12 months from Sept 2020. Of these individuals, 163 (26{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809}) had a SARS-CoV-2 infection. The team used genome sequencing to identify the variant:

  • 71 participants had a Delta variant infection
  • 42 had an Alpha variant infection
  • 50 had a pre-Alpha variant infection

The scientists used the secondary attack rate (SAR) to study the spread of the SARS-CoV-2 virus in households. The SAR for exposed household contacts for the Delta variant was 26{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809}, regardless of vaccination status. However, the researchers found that 25{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809} of vaccinated household contacts tested positive for the SARS-CoV-2 Delta virus compared with roughly 38{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809} of unvaccinated household contacts.

Dr. Simon Clarke, who is an associate professor in cellular microbiology at the University of Reading and was not involved in the study, says:

“These findings show that the vaccines remain an effective way to drive down [SARS-CoV-2] infection, but they are not a silver bullet. Infection in the wider community can still be amplified by transmission at home.”

The ability of the vaccine to prevent infection with the Delta variant in the household was roughly 34{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809}.

Interestingly, the study found vaccination status to have no effect on the maximum amount of the SARS-CoV-2 Delta virus present, known as the peak viral load. Other studies have found similar viral loads in nasal swabs, irrespective of vaccine status.

“These similar peak viral loads in vaccine breakthrough infections may explain why infected vaccinated people were just as likely to pass on infection as infected unvaccinated people,” says Prof. Peter Openshaw, professor of experimental medicine at Imperial College London.

Despite no difference in viral load, the body reduced the amount of SARS-CoV-2 Delta in the airways more quickly in vaccinated people than in unvaccinated people.

Speaking with Medical News Today, Dr. Sarah Pitt, principal lecturer at the School of Applied Sciences, University of Brighton, explained: “What is interesting about this study is because they followed people up for 3 weeks, they could see how much virus they were shedding and for how long […]. This could be a useful finding, as it might provide new information about how long people should self-isolate for once they have tested positive.”

The researchers noted that the time between the completion of vaccination and study recruitment was longer for PCR-positive contacts than for PCR-negative contacts. This is an important finding according to Prof. Penny Ward, independent pharmaceutical physician, visiting professor in pharmaceutical medicine at King’s College London.

She says that this may indicate that “waning individual protection may occur from 3 months rather than the 6 months currently scheduled for booster doses.”

The researchers note that they only included the contacts of symptomatic individuals in this study. Despite each of these people being the first member of their household to have a PCR-positive test, it is possible that another household member may already have had the infection.

According to Professor Emeritus Keith Neal of the University of Nottingham, this study helps with “understanding why Delta is now the predominant variant worldwide. Delta is able to spread between vaccinated people in a way previous variants did not.”

The research shows that the Delta variant of the SARS-CoV-2 virus can transmit from fully vaccinated people, who can have similar amounts of it in their airways as someone who is unvaccinated.

However, the amount of the virus in the airways of a fully vaccinated individual clears more quickly, suggesting that the risk of transmission lasts for less time than it would if they were not vaccinated.

Dr. Clarke says: “[T]he fact that a vaccine reduces someone’s chance of getting [the infection] in the first place means that while the vaccines don’t provide complete protection against transmission, they are not completely ineffective.”

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Neurological complications: COVID-19 vs. COVID-19 vaccines

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A health worker administers the AstraZeneca COVID-19 vaccine at a mass vaccination center at Holm View Leisure Centre on March 2, 2021, in Barry, Wales. Matthew Horwood/Getty Images
  • Vaccines are proving effective at reducing SARS-CoV-2 infections, hospitalizations, and deaths.
  • All approved vaccines have been through randomized clinical trials to test their quality, safety, and efficacy.
  • However, the rapid development of the COVID-19 vaccines means that these trials were not large enough to detect very rare adverse events.
  • A recent study found that the risk of neurological complications was higher in people with a positive COVID-19 test than in those who had received COVID vaccines.

COVID-19 vaccines undergo testing in large randomized clinical trials before being licensed for use.

The Oxford-AstraZeneca (ChAdOx1 nCoV-19) vaccine underwent testing in more than 11,000 people from across the United Kingdom and Brazil. Additionally, over 43,000 individuals engaged in testing for the Pfizer-BioNTech (BNT162b2) vaccine trial.

Despite the large size of these studies, they were not able to detect very rare adverse events — those that occur in fewer than 1 person out of 10,000.

As more of the world’s population becomes vaccinated against SARS-CoV-2, the risk–benefit evaluations of these vaccines are increasingly important.

Identifying rare adverse events associated with the vaccines is now a global scientific priority.

An increased risk of cerebral venous sinus thrombosis following the Oxford vaccine is one example of a rare adverse event associated with the vaccines. Some countries have limited the use of this vaccine in low-risk individuals until researchers have collected further information.

Scientists in the U.K. recently completed a large, population-based study. They compared the risk of neurological complications in people with a SARS-CoV-2 infection with individuals who had recently received a first dose of either the Oxford-AstraZeneca or Pfizer-BioNTech vaccines.

Their results appear in Nature Medicine.

Although SARS-CoV-2 predominantly affects the respiratory system, there is evidence that coronaviruses can attack the nervous system. This may result in various complications.

Very rare neurological events also have links with COVID-19 vaccines, including transverse myelitis, Guillain-Barré syndrome, and Bell’s palsy.

Researchers at the University of Oxford, U.K., led the recent study to investigate these very rare events by taking real-world data from over 32 million healthcare records of vaccinated people in England.

This data included 2 million individuals with a positive SARS-CoV-2 test — of these, about 90{cfdf3f5372635aeb15fd3e2aecc7cb5d7150695e02bd72e0a44f1581164ad809} tested positive before vaccination.

The scientists calculated the risk of developing neurological complications within 28 days of a first dose of either the Oxford-AstraZeneca or Pfizer-BioNTech vaccines or within 28 days of a positive SARS-CoV-2 PCR test.

The results indicated an increased but low risk of Guillain–Barré syndrome and Bell’s palsy following a first dose of the Oxford–AstraZeneca vaccine. There was also an increased but low risk of hemorrhagic stroke following a first dose of the Pfizer–BioNTech vaccine.

The authors estimated 60 excess cases of hemorrhagic stroke per 10 million people who had received the Pfizer-BioNTech vaccine and 123 extra events of encephalitis meningitis and myelitis per 10 million people with a SARS-CoV-2 infection.

They also estimated 38 excess cases of Guillain–Barré syndrome per 10 million people receiving the Oxford-AstraZeneca vaccine and 145 excess cases per 10 million individuals after a positive SARS-CoV-2 test.

Using a set of data from Scotland, the authors were able to replicate the key finding that the Oxford-AstraZeneca vaccine was associated with an increased risk of subsequent Guillain–Barré syndrome.

These results suggest a greater risk of developing neurological complications following a SAR-CoV-2 infection than following either vaccine.

Prof. Carol Coupland from the University of Nottingham in the U.K. — one of the authors of the paper — says, “this analysis provides important information about which neurological conditions could be linked with COVID-19 vaccination or infection.”

“Overall, the findings from this study show that the risks of hospital admission with nervous system complications associated with COVID-19 infection are greater than the risks associated with COVID-19 vaccinations; highlighting the benefits of the ongoing vaccination programs.”

– Prof. Coupland

The authors of the paper note there were limitations to this study, which need acknowledging:

  • The data came only from England, although there was some data from Scotland in the secondary analysis. Therefore, rates of complications might vary between populations.
  • The analysis only looked at hospital admissions and mortality, meaning it may not have included anyone with milder neurological conditions. Therefore, the scientists could have underestimated the overall rates of neurological adverse events from vaccination and infection.
  • Due to data limitations, the researchers could only examine risks associated with the first vaccine dose.

Scientists will need to monitor these rare events continually as younger people are vaccinated. Although rare, these events can cause lifelong problems, including disabilities, which may require long-term care.

The study authors say that further work is necessary to investigate the link between the Oxford-Astrazeneca vaccine and Guillain-Barré syndrome. They suggest antibodies against the vaccine may react with components of the peripheral nerves.

The authors hope this study provides information that may help with earlier diagnosis and planning the allocation of healthcare resources. Understanding these events will also help establish clinical practice moving forward with a vaccinated population.

Dr. Martina Patone, a medical statistician at the Nuffield Department of Primary Care Health Sciences at the University of Oxford, and co-lead author, tweeted:

“Due to limited sample size, clinical trials cannot detect very rare adverse events [rarer than 1 in 10,000]. Therefore, vaccine surveillance continues after the vaccine is in use. Understanding the adverse events of each vaccine may change or update recommendations and assure their safety.”

Medical News Today spoke with Prof. Saad Shakir, Director of the Drug Safety Research Unit in Southampton, U.K., who was not involved in the study. For him, the take-home message is that “COVID-19 vaccines have been remarkably safe. [And] there has been only a small number of very rare adverse reactions.”

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