GSK advances mRNA flu shot to late-stage trial after positive Phase 2 data
GSK is progressing its mRNA-based seasonal flu vaccine into a Phase 3 study following a Phase 2 trial that indicated stronger immune responses compared with conventional vaccines. The UK-based pharmaceutical company disclosed the plan on Tuesday. The trial will test a newer formulation of the candidate.
The announcement marks a significant step in applying messenger RNA technology beyond COVID-19, where it proved highly effective. Seasonal influenza vaccines have traditionally relied on egg-based or cell-culture production, which can be slower to update against circulating strains. An mRNA approach could allow faster reformulation and potentially stronger protection, as suggested by the Phase 2 results. GSK’s decision to move to a late-stage trial with a newer formulation indicates confidence in the platform’s adaptability, though large-scale efficacy and safety data remain pending.
If successful, an mRNA flu vaccine could reshape annual vaccination campaigns, offering quicker strain updates and possibly better protection for older adults and immunocompromised individuals who respond poorly to conventional shots. Manufacturers may face production flexibility, while public health systems could see improved seasonal coverage. However, uptake depends on real-world effectiveness, cold-chain logistics, and public trust in a newer technology. The impact could be substantial but will unfold over several years, contingent on Phase 3 outcomes and regulatory review.