Moderna says vaccine effective on variants, but tests booster shot

There was some good news from Moderna on its vaccine’s effectiveness against variants of the coronavirus on Monday, though “out of an abundance of caution” they are testing a booster shot against one variant to watch.

Moderna said Monday that its studies showed “no significant impact” in the levels of neutralizing antibodies produced against the U.K. variant, a positive sign.

But for the South African variant, the vaccine produced a “six-fold” decrease in neutralizing antibodies. Still, the level of antibodies produced remains “above levels that are expected to be protective,” the company said.

Given this drop in antibody levels, the company said that to be on the safe side, it will begin studying a new version of its vaccine specifically designed to fight the South African variant, that can be given as a booster shot.

The company said it would begin Phase 1 trials to “evaluate the immunological benefit of boosting with strain-specific spike proteins.”