Rapivab Approved to Help Treat Flu

Rapivab (peramivir) has been approved by the U.S. Food and Drug Administration to treat influenza.

The intravenous drug inhibits an enzyme that releases viral particles from infected cells, the FDA explained Monday in a news release. Rapivab is approved for people 18 and older who have had flu symptoms for no more than two days.

Flu affects up to 20 percent of the American population each season, hospitalizing more than 200,000 people annually, the agency noted.

Rapivab's safety and effectiveness were evaluated in a clinical study of almost 300 people with a confirmed case of the flu. Those given the newly approved drug had symptoms ease about 21 hours sooner than people who didn't take the drug, the FDA said.

Common side effects included diarrhea and serious skin reactions. And the FDA stressed that Rapivab and other antiviral drugs are not substitutes for getting the annual flu vaccine.

Rapivab is produced by BioCryst Pharmaceuticals, based in Durham, N.C.