Researchers have found that a compound CS-8958 is a better alternative antiviral to fight bird flu, as the novel compound is more effective against the pathogenic H5N1 avian influenza virus.

For bird flu antiviral drugs are the most important countermeasure. Yoshihiro Kawaoka, a professor of pathobiological sciences at the UW-Madison School of Veterinary Medicine and senior author of the new study states that a threat is posed by emerging strains resistant to existing drugs, particularly oseltamivir (Tamiflu).

Kawaoka and a group of researchers from Japan, Vietnam, and Indonesia tested a novel neuraminidase inhibitor R-125489 and its prodrug CS-8958, on mice in a laboratory. The researchers found that as compared to a five-day course of oseltamivir, CS-8958’s single intranasal dose administered within two hours after infection with H5N1 influenza virus showed survival rate that was much higher and virus levels were also low. The drug against highly pathogenic and oseltamivir-resistant strains of H5N1 virus was highly effective.

Apart from this mice was protected against the H5N1 infection when the dose of CS-8958 was given seven days before infection with the virus.

Kawaoka said, "This compound requires only a single administration for both treatment and prophylaxis. Such prophylaxis would be highly desirable for seasonal influenza as well as a potential pandemic situation."