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 showed that antibodies produced by
the Moderna vaccine were six times less effective against the South
African variant.
The U.K. variant did not appear to reduce the potency of the
antibodies, but other research has suggested it 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.
