Potential treatment for influenza discovered

A novel experimental drug has shown promise in treating influenza, preventing lung injury and death from the virus in preclinical studies, researchers claim.
Scientists found that a drug called Eritoran can protect mice from death after they have been infected with a lethal dose of influenza virus.The potential value of this drug as single therapy or in combination with antivirals is further supported by previous research that found that it is safe for use in humans.

Previous scientific studies have revealed that acute lung injury caused by the influenza virus is the result of an immune reaction mediated by a protein called Toll-like receptor 4 (TLR4).
Senior author Stefanie Vogel, Professor of Microbiology and Immunology and Medicine at the University of Maryland, and colleagues previously demonstrated that mice that lack the ability to signal through TLR4 are highly refractory to influenza-induced lethality.

In their new study, they extend these findings by showing that Eritoran - a synthetic inhibitor of TLR4, originally developed for treatment of sepsis - improved clinical symptoms and prevented death when administered up to six days after infection with the influenza virus.
Existing antiviral medications must be administered within two days of infection to be optimally effective. Annual influenza epidemics are estimated to result in three to five million cases of severe illness and 250,000 to 500,000 deaths yearly worldwide, researchers said.

The virus is continually evolving and new variants give rise to seasonal outbreaks. Increasing resistance to existing antiviral therapies and the short time-frame in which these agents are effective highlight the critical need for new treatments, such as Eritoran, they said.

"Currently, vaccines and antiviral medications are the two main approaches to preventing influenza. Problems associated vaccine development may limit efficacy and/or vaccine availability," said Vogel. "Our research seems to show that Eritoran could provide doctors with a new tool in their flu-fighting toolbox, as well as several more days to treat the sickest of patients successfully," said researchers.