Researchers from the Doherty Institute, the Kirby Institute and institutions globally have studied antibody-based therapy in a trial for the treatment of influenza B.

They examined the effect of injected Intravenous Immunoglobulin for Influenza (Flu-IVIG), antibodies from the blood of people exposed to or vaccinated against the influenza virus, on individuals who were hospitalised with severe influenza.

They revealed insights into the complex mechanisms underlying antibody-based therapies for these individuals.

Improved outcomes were observed in patients hospitalised with influenza B who received treatment with Flu-IVIG, an anti-influenza hyperimmune intravenous immunoglobulin.

Doherty Institute former researcher Dr Hillary Vanderven said: “Improved outcomes in patients with influenza B were associated with a specific group of antibodies when they were present in greater quantities.

“Additionally, Flu-IVIG proved beneficial for individuals with low levels of anti-influenza B antibodies.

“However, we were surprised to discover that higher levels of these same antibodies were associated with poorer outcomes in patients with influenza A and Flu-IVIG didn't benefit those with low levels of anti-influenza A antibodies.”

Doherty Institute laboratory head and University of Melbourne professor Stephen Kent said that the lack of clinical benefits from treatment with antibodies in influenza A patients could be due to various factors.

Kent added: “Understanding the intricate balance between the protective and the potentially harmful roles of the antibodies in the immune system is very complex but crucial.

“Things like the type of influenza virus, clinical presentation and the patient’s immunological history may impact on the antibodies’ functions and their ability to kill influenza-infected cells. This is something that needs to be further investigated.”