influenza A (H1N1) haemagglutinin, recombinant

influenza A (H1N1) haemagglutinin, recombinant is a protein subunit vaccine candidate developed by GSK Biologicals for the prevention of influenza caused by the H1N1 virus strain. The vaccine utilizes a recombinant version of the haemagglutinin (HA) protein, the primary surface glycoprotein of the influenza virus, which is typically expressed in an insect cell-baculovirus system. Its mechanism of action involves the induction of a humoral immune response, specifically the production of neutralizing antibodies that target the HA protein to block viral attachment and entry into host respiratory cells. Developed primarily in response to the 2009 H1N1 pandemic, this recombinant antigen was often evaluated in clinical trials in combination with GSK's AS03 adjuvant system—an oil-in-water emulsion containing squalene and alpha-tocopherol—to enhance immunogenicity and support dose-sparing strategies. While it demonstrated safety and immunogenicity in Phase 1 and 2 trials, it was not widely commercialized as a standalone product following the pandemic's conclusion.

Other names

Recombinant H1N1 Hemagglutinin VaccinerH1N1 HArH-1N1 HArH 1N1 HA