Post-marketing safety and effectiveness evaluation of the intravenous anti-influenza neuraminidase inhibitor peramivir (I): a drug use investigation.

Peramivir is the only intravenous formulation among anti-influenza neuraminidase inhibitors currently available. Peramivir was approved for manufacturing and marketing in Japan in January 2010. We conducted a drug use investigation of peramivir from October 2010 to February 2012 and evaluated its safety and effectiveness under routine clinical settings. We collected data of 1309 patients from 189 facilities across Japan and examined safety in 1174 patients and effectiveness in 1158 patients. In total, 143 adverse events were observed with an incidence rate of 7.33% (86/1174). Of these, 78 events were adverse drug reactions (ADRs) with an incidence rate of 4.34% (51/1174). The most frequently reported ADRs were diarrhea, vomiting, and nausea, with incidence rates of 1.87% (22/1174), 0.85% (10/1174), and 0.68% (8/1174), respectively. Moreover, no ADR was reported as serious. ADR onset was within 3 days after the start of peramivir administration in 91.0% (71 events) of the 78 ADRs, and ADRs were resolved or improved within 7 days after onset in 96.2% (75 events) of the 78 ADRs. Neither patient characteristics nor treatment factors appeared to significantly affect drug safety. With regard to effectiveness, the median time to alleviation of both influenza symptoms and fever was 3 days, including the first day of administration. The present study demonstrates the safety and effectiveness of peramivir under routine clinical settings.