Story at a glance
- As the COVID-19 spike protein shows signs of mutating, Moderna is developing an extra booster shot to help fight the variant emerging from South Africa.
- Two new strains seen in the U.K. and South Africa show structural differences that could make them more contagious.
Drugmaker Moderna announced on Monday that while it’s current COVID-19 vaccine proved to neutralize antibodies from new strains of COVID-19 emerging in countries like South Africa and England, the company is launching fresh clinical trials to test a booster dose to support immunity against the evolving virus.
The booster candidate in development, dubbed mRNA-1273.351, will feature the same messenger RNA technology the company’s approved two-dose vaccine uses but target the specific spike proteins found in the South African COVID-19 variant.
Phase 1 studies will commence in the U.S. to see if it bolsters the immunity effects of the current vaccine.
“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,” Stéphane Bancel, Moderna's CEO, said in the statement.
Recent mutations seen in the COVID-19 spike protein have alarmed public health officials due to the more contagious structure of the cell. Both strains found in the United Kingdom and South Africa showcase mutations on the spike protein’s binding receptors, which appear to make it more transmissible.
The South Africa strain in particular also shows changes in the original COVID-19’s viral genome, or the part of the virus that contains its DNA or RNA.
Emerging data from Moderna’s additional vaccine trials suggest that it produced an immune response to both strains; it was more effective against the U.K. variant than the South African mutation.
The lower antibody count found when testing the vaccine against the South Africa variant “may suggest a potential risk of earlier waning of immunity” regarding emerging variants connected to the South Africa strain.
Bancel added in the statement that Moderna will focus its booster candidate to fight the South Africa variant more efficiently.
“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 against this and potentially future variants,” he said.
Early studies offer evidence that the current approved vaccines, which consist of Moderna and Pfizer and BioNTech’s vaccines, will provide protection against new COVID-19 strains — though many await peer review.
Speaking on NBC News today, Anthony Fauci, the leading White House coronavirus advisor, said that public health experts still regard approved vaccines to be effective against the U.K. and South African variants, but pharmaceutical companies will need to be ready to augment existing formulas.
“I don't want people to think that the vaccines are not effective against them - they are,” Fauci said. “However, we really need to make sure that we begin, and we already have, to prepare, if it's necessary, to upgrade the vaccines.”