Gen ID to develop new bird flu drugs

In its research efforts with S2, GEN ID is seeking to develop yet another class of compounds to counteract the resistance that H5N1 is acquiring through mutations.

The mortality rate in avian flu infection reported by the World Health Organization (WHO) is over 50%. The first outbreak of documented avian flu infection with H5N1 virus subtype was in 18 patients and resulted in six deaths in Hong Kong in 1997 (33%). As of May 5, 2006, there have been 206 confirmed human cases of H5N1 influenza worldwide, of whom 114 have died (55%).

Current treatment of H5N1 avian influenza infection includes the use of antiviral therapy such as ribavirin and amantadine and neuraminidase inhibitors such as oseltamivir and zanamivir. However, the presence of Asp31 in the M2 protein of some variants of H5N1 confers resistance to the antiviral compounds, making this treatment option ineffective.

While the neuraminidase inhibitors group of compounds are effective against influenza infections, recent isolates of H5N1 have been shown to contain amino acid substitutions in the neuraminidase enzyme, making these variants resistant to this alternative treatment option.