Japan Proposes Influenza Drug To Treat Ebola

The Japanese government said this week that it is prepared to make an influenza drug that is not approved for the treatment of Ebola available to West African countries hard-hit by the deadly virus.

“We have been informed that there are inquiries from those countries about the medicine developed by a Japanese company that may be effective in treating the virus,” Yoshihide Suga, chief cabinet secretary, said at a press conference last week. If requested to do so by the World Health Organization, “we will provide it in cooperation with the company,” Suga said.

The drug, favipiravir, brand-named Avigan, is manufactured by Fujifilm subsidiary Toyama Chemical and was approved in Japan as an influenza treatment earlier this year.

Avigan, a polymerase inhibitor, stifles viral gene replication within infected cells to prevent the spread of the virus to uninfected cells. As a treatment for influenza, the drug is an alternative to neuraminidase inhibitors such as Tamiflu and Relenza, which act by inhibiting the release of viral particles from infected cells.

Although Avigan has not been tried on Ebola patients, a Fujifilm spokeswoman says the company is aware of tests performed by independent researchers that show it reduces Ebola infection in mice. The company, she says, has sufficient supplies of favipiravir for more than 20,000 people and has developed a system for continuous production of the drug.

Avigan joins a growing roster of potential treatments for the disease, which has killed nearly 1,500 people in the current outbreak. One drug, ZMapp, an antibody mixture developed by Mapp Biopharmaceutical, seemed effective for two American aid workers, who were able to leave an Atlanta hospital late last month after being infected in Africa. However, a doctor in Liberia died after being treated with ZMapp.

Other drugs in development to treat the disease include an siRNA compound from Tekmira Pharmaceuticals and an antisense drug from Sarepta Therapeutics.

And the National Institute of Allergy & Infectious Diseases will begin human safety tests this week on a GlaxoSmithKline vaccine in development for the treatment of Ebola. In parallel, a British-based consortium will test the vaccine in volunteers in the U.K. and Africa.