The World Health Organization has announced its recommendations for the 2026–2027 Northern Hemisphere influenza vaccine composition, highlighting two key developments: the continued spread of A (H3N2) subclade K and the growing circulation of new B/Victoria lineage strains. In rapid response, Sino Biological, Inc., a global leader in recombinant technology, has launched a comprehensive panel of antigens for the 2026-2027 Northern Hemisphere influenza vaccine strains to accelerate influenza vaccine development.
Since its identification in August 2025, H3N2 subclade K (J.2.4.1) has become the dominant influenza A strain worldwide. Defined by the T135K and S144N mutations, this strain exhibits enhanced immune escape, prompting WHO’s selection of A/Darwin/1454/2025 (egg-based, cell-based) as the new H3N2 reference viruses. The H1N1 component has been updated to A/Missouri/11/2025 (egg-based, cell-based). Alongside H3N2, influenza B activity is rising sharply. In regions such as Hong Kong and the U.S., the proportion of B/Victoria lineage viruses recently increased from 6% to over 20%. These trends led WHO to recommend B/Tokyo/EIS13-175/2025 (egg-based) and B/Pennsylvania/14/2025 (cell-based) strains for the upcoming season.
To support global influenza vaccine research and development, Sino Biological has launched an extensive portfolio of recombinant antigens for the 2026-2027 Northern Hemisphere influenza vaccine strains, spanning key viral antigens including Hemagglutinin (HA), Neuraminidase (NA), and Nucleoprotein (NP). These include H1N1 reagents such as A/Missouri/11/2025 (H1N1) HA Trimer (HEK293 cell-expressed, purity ≥90% verified by SEC-MALS, activity validated by ELISA), NA, and NP antigens, which are available now. H3N2 subclade K proteins, including recombinant HA, NA, and NP aligned with A/Darwin/1454/2025, are also available now. Influenza B reagents for B/Tokyo/EIS13-175/2025 and B/Pennsylvania/14/2025 are in development. The company also offers stable HA trimers that are high-purity and SEC-MALS–validated, maintaining native conformation for accurate immune characterization.
Dr. Rob Burgess, Chief Business Officer at Sino Biological US, stated, "Our mission is to provide the scientific community with the highest quality tools as rapidly as possible when infectious disease evolution threatens global health preparedness. Sino Biological remains committed to delivering reliable reagents that advance global influenza preparedness and vaccine innovation." This initiative is critical as it addresses the evolving nature of influenza viruses, which can impact vaccine efficacy and public health outcomes. The availability of these antigens enables researchers and vaccine manufacturers to develop more effective vaccines, potentially reducing the burden of influenza-related illnesses and deaths worldwide. For more information, visit https://www.sinobiological.com.
