Moderna starts trial for Omicron-specific booster shot

Moderna Inc said it had started a mid-stage study, testing a booster dose of its COVID-19 vaccine specifically designed to target the Omicron coronavirus variant, a day after rival Pfizer Inc launched a similar trial. The company said while a third shot of its original coronavirus vaccine increased neutralizing antibodies against the variant at the lower dose, their levels declined six months after the booster dose was administered. However, neutralizing antibodies remained detectable in all participants, Moderna said.