A healthcare volunteer primes a syringe with the Moderna Covid-19 vaccine in Lincoln, Neb. | Kenneth Ferriera/Lincoln Journal Star via AP
Moderna will develop a Covid-19 booster shot designed to be more effective against emerging strains of the coronavirus, the Massachusetts manufacturer announced Monday.
New strains of the coronavirus have emerged in the United Kingdom, South Africa and Brazil, along with concerns that they could make vaccines less effective, and be more transmissible or deadly.
Moderna’s announcement comes days after the U.S. government’s top infectious disease expert, Anthony Fauci, said that the Biden administration is “paying very close attention” to the variants. “There are alternative plans if we ever have to modify the vaccine,” said Fauci, director of the National Institute of Allergy and Infectious Disease, at a White House briefing Thursday.
Moderna is testing two booster-shot options — one specifically aimed at the South African variant and another to broadly fight new mutations. Laboratory research using blood from people and monkeys who had received the company’s vaccine found that the U.K. variant did not appear to reduce the production of neutralizing antibodies. But the South African variant showed a sixfold reduction, the company said.
Other research has suggested the U.K. variant is more transmissible than previous versions of the virus. On Friday, a U.K. government science advisory board said there “is a realistic possibility” that the U.K. variant is also more deadly.
Moderna said the development of the booster is a precaution because its already-authorized two-dose regimen still offered substantial protection against the U.K. and South African strains in the lab study.
“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,” Moderna CEO Stéphane Bancel said in a statement. The company is starting human trials for the South African booster shot “out of abundance of caution,” he added.
Moderna conducted the laboratory study in collaboration with NIAID, and has published the research online in bioRxiv ahead of peer review. The company said it will submit the study to a peer-reviewed journal.