FLICKR, SANOFI PASTEURHealth authorities in Japan on Friday (February 23) approved a new flu medication, called baloxavir marboxil (Xofluza), that aims to stop the virus within one day, according to The Wall Street Journal.

The drug works by blocking the flu virus’s ability to use the host cell for replication. That’s a different mechanism from oseltamivir (Tamiflu), an anti-influenza medication available in the U.S. that works by blocking the virus’s neuraminidase enzyme, preventing its escape from the host cell.

“The data that we’ve seen looks very promising,” Martin Howell Friede, head of the World Health Organization’s advisory on vaccines, told the Journal earlier in the month. “This could be a breakthrough in the way that we treat influenza.”

Data from the drugmaker, Shionogi, show that while Xofluza works days faster than Tamiflu in stopping the flu virus, symptoms wrap up in about the same timeframe for either medication. Roche, which makes Tamiflu, has acquired the license to sell Xofluza internationally, but it will be another year until it could be available in the U.S., according to the Journal.

According to Nikkei Asian Review, Xofluza is the first drug Japan has approved via its fast-track system and will be available to patients there once the pricing is set.