Responding to a request from the Centers for Disease Control and Prevention, the Food and Drug Administration on Friday approved emergency use of the experimental intravenous antiviral drug peramivir to treat hospitalized patients with pandemic H1N1 influenza.
Tamiflu, the primary drug used to treat swine flu, is given orally, and Relenza, also used, is given as a nasal spray. Some experiments have been conducted with an intravenous form of Relenza and it has been credited with saving at least one swine flu patient's life, but it is considered more experimental than peramivir.
The problem with existing drugs is that some people have difficulties tolerating the oral Tamiflu and that the nasal spray Relenza may not get deep enough into the lungs to reach the swine flu virus when it causes viral pneumonia. The emergency use authorization says peramivir can be used when other drugs have failed or when delivery by a route other than intravenous is not expected to be feasible.
Peramivir, manufactured by BioCryst Pharmaceuticals Inc., is still in Phase 3 clinical trials. Known side effects include diarrhea, nausea, vomiting and decreases in white blood cell count, all of which stop when its use is halted. It has not been tested in pregnant women.
-- Thomas H. Maugh II