The study found that a booster dose of the variant-targeting formula was more effective than a booster of the original vaccine, but both raised antibody levels, Moderna said in a press release. The research is not yet peer-reviewed.
The boosters also appeared as safe as earlier shots, with volunteers reporting side effects similar to a second dose of the original Moderna vaccine.
There are several potential coronavirus boosters in lab and human studies as governments and pharmaceutical companies brace for possibly fading immunity in the face of spreading variants.
“As we seek to defeat the ongoing pandemic, we remain committed to being proactive as the virus evolves,” Moderna CEO Stéphane Bancel said in a statement. “We are encouraged by these new data, which reinforce our confidence that our booster strategy should be protective against these newly detected variants.”