Moderna on Monday said its experimental mRNA-based flu vaccine produced a stronger immune response than a currently available shot in a late-stage trial, clearing a path forward for the product and the company's separate combination flu and Covid jab.Moderna in May voluntarily withdrew an application seeking approval of its combination shot targeting Covid-19 and influenza, saying it had plans to resubmit it with efficacy data from the phase three trial on its standalone flu vaccine. That decision came afte ...