Moderna making booster shot to fight Covid-19 variants

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.