Moderna Rises Despite GSK Advancing Competing mRNA Flu Vaccine
Moderna's stock (NASDAQ:MRNA) rose by 6% despite GlaxoSmithKline (NYSE:GSK) advancing its rival mRNA-based flu vaccine into Phase III trials. Investors appear to be viewing the move as validation of the broader mRNA platform rather than a direct threat to Moderna’s mFlusvia, which received FDA approval in August 2026 and is projected for $831 million in sales by 2032. GSK's Phase III trial follows positive mid-stage results showing higher immune responses compared to standard flu vaccines. The company plans to begin the late-stage study in September 2026, targeting both haemagglutinin and neuraminidase proteins for improved efficacy. Despite this development, Moderna’s recent success with its mRNA melanoma vaccine has rekindled investor confidence. Analysts suggest that while GSK's move could eventually compete directly with mFlusvia, the broader market is interpreting it as a sign of continued momentum in mRNA technology. Merck (NYSE:MRK) remains involved in Moderna’s cancer vaccine development and holds economic rights to the therapy.
