GSK's mRNA flu vaccine shows stronger immune response than standard shots in phase 2, prompting phase 3 launch

GSK reported that its experimental mRNA seasonal influenza vaccine generated higher immune responses than both standard and high-dose flu shots in a phase-2 study involving nearly 1,000 adults.

The finding is notable because current flu vaccines have variable effectiveness, typically ranging from 20% to 60% over the past 15 years. By targeting both hemagglutinin and neuraminidase, the mRNA candidates aim to improve protection.

GSK said the safety and reactogenicity profile was acceptable, although detailed numbers were not released. Based on the data, the company will commence a pivotal phase-3 trial later this month.