The antibodies target a stable part of the bird flu virus, ensuring that the immune protection can resist new variants and offer long-term protection against the globally spreading airborne infection. It helps in preventing severe bird flu in monkeys.
A prophylactic antibody-based immune therapy protects monkeys against severe disease caused by H5N1 avian flu, University of Pittsburgh and NIH Vaccine Research Center researchers report in Science.
The broadly neutralizing antibody, which recognizes a relatively stable region of the bird flu virus, is less prone to losing its efficacy than antibodies targeting influenza’s more mutation-prone structures.
This feature ensures that the immune protection can withstand the possible emergence of virus variants, akin to the SARS-CoV-2 mutants that evolved during the COVID-19 pandemic, and provide lasting protection against a globally spreading airborne infection.
“This type of prevention can be very useful in controlling infection outbreaks and containing the bird flu pandemic,” said co-corresponding author Douglas Reed, Ph.D., associate professor of immunology at Pitt’s School of Medicine and the Center for Vaccine Research.
“In our testing, the antibody performed beautifully. The antibody could be useful as a prophylactic of severe disease in vulnerable populations, and it also helped us establish the testing threshold for antibody levels in the blood, which would be useful for judging the immune protection generated by a universal flu vaccine.”
In a new study, monkeys pre-treated with a moderate dose of a broadly neutralizing MEDI8852 antibody were universally protected against severe disease and death.
In addition to confirming the antibody’s efficacy in preventing serious adverse health outcomes, scientists were also able to establish its minimum serum concentration required for protection — a measurement useful for establishing the protective threshold of a potential universal flu vaccine.
The research sets the stage for the development of medical countermeasures against future influenza virus pandemics. Serum levels of MEDI8852 sufficient for protection remained stable for 8 to 12 weeks.
It suggests that, if given early, it could protect first responders and others caring for patients at the beginning of an outbreak of H5N1.
(With inputs from ANI)
