Moderna on Wednesday said its flu vaccine had generated a stronger immune response against all four A and B strains of the influenza virus compared to traditional flu shots in a late-stage trial. The effectiveness of Moderna’s flu vaccine was demonstrated across all age groups, and was found to be safe and tolerable, according to the company. Moderna also said it had found that its shot was equal or superior to Sanofi’s high-dose flu vaccine in a separate early head-to-head study.