GSK Shares Surge 1.82% as RSV Vaccine Enters Canadian Programs Trading Volume Ranks 270th in Market Activity

On September 9, 2025, , . The move followed news of its RSV vaccine, Arexvy, being integrated into publicly funded immunization programs in Canada for the 2025-2026 season. The vaccine is expected to dominate publicly funded RSV doses, targeting adults aged 60 and older, including those in long-term care facilities, and extending eligibility for 50-74-year-olds under medical guidance.

GSK’s inclusion of Arexvy in provincial programs aligns with updated National Advisory Committee on Immunization (NACI) guidelines issued in March 2025. The vaccine, Canada’s first authorized RSV vaccine for older adults, is now accessible through select government-funded initiatives, enhancing its market reach. The decision underscores growing recognition of RSV’s risks in aging populations, . GSK emphasized its commitment to expanding access through collaboration with public health partners.

While the vaccine’s integration into public programs is expected to boost demand, the stock’s volume surge suggests short-term investor optimism. However, the impact on long-term revenue will depend on adoption rates and provincial funding allocations. GSK’s focus on expanding Arexvy’s availability outside publicly funded channels—via prescriptions for eligible adults—also highlights its strategy to maximize market penetration. The news contrasts with broader vaccine sector developments, such as Moderna’s patent disputes and Sanofi’s recent acquisition, which are not directly linked to GSK’s performance.

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