Comment by importantbrian

Well they have tested bivalent COVID-19 vaccines in large human trials. These boosters are functionally the same they just target different strains of COVID. I'm not an expert, but that's how flu vaccines are done. They don't have to seek re-approval for every new strain every season, and that seems fine. Maybe that's a bad practice. I don't know, but I'm comfortable deferring to experts in the field on it.