Development of Omicron-specific vaccines is under way
The variant B.1.1.529, also named Omicron, was reported by South Africa to the World Health Organization on Wednesday (Nov 24); before being classed as a variant of concern by the organization on Friday (Nov 26).
The emergence of the new variant has been pre-empted by vaccine developers: who are now spurring their response strategies into action. The two pressing questions are how effective current vaccines will be against the new variant; and how long it will take to create a new vaccine if required.
Moderna's three-point plant
On Friday, Moderna announced its three-point plan to tackle Omicron, in the event that its current vaccine regiment plus 50 μg booster shot proves insufficient to protect against the variant.
“Since early 2021, Moderna has advanced a comprehensive strategy to anticipate new variants of concern,” it announced.
“The recently described Omicron variant includes mutations seen in the Delta variant that are believed to increase transmissibility and mutations seen in the Beta and Delta variants that are believed to promote immune escape. The combination of mutations represents a significant potential risk to accelerate the waning of natural and vaccine-induced immunity.”
Firstly, the company is assessing a higher booster dose at 100 μg. The company has already completed dosing of 306 participants in a safety and immunogenicity study. Moderna will now start testing sera from these recipients to see if it provides superior protection against Omicron than the 50 μg shot.
Secondly, the company has taken two of its multi-valent booster candidates – already designed to anticipate such mutations and in clinical studies – and started to test these against Omicron.
“The first candidate (mRNA-1273.211) includes several mutations present in the Omicron variant that were also present in the Beta variant of concern. The company has completed dosing in a potentially pivotal safety and immunogenicity study of mRNA-1273.211 at the 50 μg (N=300) and 100 μg (N=584) dose levels.
“A second multi-valent candidate (mRNA-1273.213) includes many of the mutations present in the Omicron variant that were also present in the Beta and Delta variants. The company has completed dosing at the 100 μg (N=584) dose level and also plans to explore the 50 μg dose level in approximately 584 participants.
“Moderna will rapidly expand testing of sera from completed and ongoing multi-valent booster studies to determine if these multi-valent candidates are able to provide superior neutralizing protection against Omicron.”
Thirdly, Moderna will ‘rapidly advance’ an Omicron-specific booster candidate (mRNA-1273.529): a process that it has already been through with beta and delta specific boosters. "The company has repeatedly demonstrated the ability to advance new candidates to clinical testing in 60-90 days," it says.
Omicron: The challenges
The Omicron variant contains more than 30 changes to the spike protein, which is commonly used by vaccines to train the body to recognise the virus.
“Omicron has a large number of mutations, some of which are concerning,” noted the WHO.
It adds that it is not yet clear whether Omicron is more transmissible compared to other variants; or whether infection with Omicron causes more severe disease.
Preliminary evidence suggests there may be an increased risk of reinfection with Omicron, but information is limited.
Vaccines: the WHO is working with technical partners to understand the potential impact of this variant on vaccines and other countermeasures.
Tests: PCR tests can be used to detect Omicron infections. Studies are ongoing to determine whether there is any impact on other types of tests, including rapid antigen detection tests.
Treatments: Corticosteroids and IL6 Receptor Blockers will still be effective for managing patients with severe COVID-19. Other treatments will be assessed to see if they are still as effective given the changes to parts of the virus in the Omicron variant.
Johnson & Johnson: 'We will not be complacent'
In a statement this morning, Johnson & Johnson said it had started testing blood serum from participants in booster studies to look for neutralizing activity against the Omicron variant.
It also confirmed it is working on an Omicron-specific vaccine and ‘will progress it as needed’.
“The new Omicron variant highlights the importance of continued surveillance, testing and vaccination to prevent hospitalizations and deaths from COVID-19. We remain confident in the robust humoral and cell-mediated immune responses elicited by the Johnson & Johnson COVID-19 vaccine demonstrated by the durability and breadth of protection against variants to date in clinical studies,” said Mathai Mammen, M.D., Ph.D., Global Head, Janssen Research & Development LLC., Johnson & Johnson.
“We will not be complacent. Building on our long-term collaboration with scientists on the ground in South Africa and the ongoing real world effectiveness studies being conducted with the Johnson & Johnson COVID-19 vaccine, we will work together to generate new data on Omicron. In parallel, we have begun work to design and develop a new vaccine against Omicron and will rapidly progress it into clinical studies if needed.”
Pfizer/BioNTech: aiming for 100 day vaccine development
BioNTech announced it has started work on a vaccine tailored to Omicron; saying it could take around six weeks to adapt the mRNA vaccine and 100 days to start shipping batches.
On Friday, it stated it will take it around 2 weeks to identify if its existing authorized vaccine provides sufficient protection or if a new vaccine against the variant will be required.