Peramivir, the Neuraminidase Inhibitor, cuts down the recovery time for influenza cases (WebMD):

The experimental drug peramivir cut short by about one-third the number of days people were sick with the flu, Japanese researchers report.

While the new drug was not directly compared with the currently available flu drugs Tamiflu and Relenza, it appears to work at least as well, says Shigeru Kohno, MD, of the Nagasaki University Graduate School of Medicine.