Moderna says its vaccine protects against new COVID-19 variants

Moderna’s vaccine is effective against new variants of the coronavirus that have emerged in Britain and South Africa. The company made the announcement on Monday.

However, it said the vaccine is less effective against the variant discovered in South Africa, so it is developing a new form of the vaccine that could be used as a booster shot against that virus.

“We’re doing it today to be ahead of the curve should we need to,” Dr. Tal Zaks, Moderna’s chief medical officer, told the New York Times in an interview. “I think of it as an insurance policy.”

He added, “I don’t know if we need it, and I hope we don’t.”

Moderna’s findings from a study that used blood samples from eight people who had received two doses of the vaccine, and two monkeys that had also been immunized.

The British variant had no impact on the levels of neutralizing antibodies — the type that can disable the virus — produced after vaccination. But with the South African form, there was a sixfold reduction in those levels.

Even so, the company said, those antibodies “remain above levels that are expected to be protective.”

But the results have not been published or peer-reviewed yet, but have been submitted to bioRxiv, which posts preliminary studies online.