Invivyd rises on late-stage trial testing COVID antibody against mRNA vaccines

Shares of drug developer Invivyd IVVD.O rise 5.17% to $1.83 premarket

Co says it has launched a late-stage trial testing its experimental COVID antibody VYD2311 against mRNA vaccines

Says study will enroll ~210 people and compare safety; adds that it will also test using the antibody and vaccines together

Says FDA asked it to closely track heart inflammation, a rare side effect previously seen after mRNA vaccinations

Adds VYD2311 is a single-shot antibody designed to protect against current COVID variants; uses same platform as IVVD drug that was cleared earlier

Shares rose ~457% in 2025