Relenza, a powder that comes in an inhaler-like device, was approved by the Food and Drug Administration, and is due on drugstore shelves Friday. A similar competing medicine in pill form is expected soon.
Patients must get a prescription from their doctors for Relenza within 48 hours of noticing early flu symptoms. The FDA approved the medication for reducing the symptoms of flu and shortening a typical six-day illness by 30 percent.
New research says Relenza actually blocks the flu virus -- both types A and B -- from reproducing. The study suggests the drug can prevent the spread of flu among family members. Between 25 million and 50 million Americans typically get the flu each winter.
Dr. Frederick Hayden of the University of Virginia in Charlottesville conducted the study during last winter's flu season. He described his results at the annual scientific meeting of the American Society of Microbiology.
In the study, 337 families who had a member suffering from flu received Relenza. Only 4 percent of family members getting the drug also got flu. By contrast, 19 percent who took a placebo drug became sick. The drug reduced the risk of getting flu by 79 percent.
While Relenza can reduce the symptoms of flu, it is not a replacement for a flu shot. Relenza costs about $45-$50 for a course of treatment -- much more than a flu shot -- and has to be taken within 24-48 hours after getting symptoms. So far, Relenza is only approved for use in treating the flu, not preventing it.
Meanwhile, another prescription drug called Tamiflu is expected to get FDA approval in a month. The drug, made by Hoffman-LaRoche, acts in the same way as Relenza, but is in pill form. Other competing pharmaceutical companies are making progress on their new flu drugs, potentially adding more remedies in the near future.
Relenza was approved by the FDA last summer and is made by Glaxo Wellcome Inc., with its American headquarters in Research Triangle Park, N.C.
Relenza will be the first of a new class of flu medicines known as neuraminidase inhibitors to reach the market.
Hayden said drug companies will have to convince both physicians and patients to look at flu differently, now that medicines are available to both treat the disease and prevent it. For instance, he said doctors may eventually become willing to prescribe the drugs over the phone without seeing patients if they report typical flu miseries during flu season.
In another report to the conference, Hayden described the results of a study of pleconaril, an experimental medicine for the common cold. The medicine was developed by Viropharma Inc. of Exton, Penn.
Doctors tested it on 1,024 people and found that it shortened the length of a typical moderate-t-severe cold from 14 days to 10½. They looked at various measures of a cold's severity, including the number of tissues used. Their count: Pleconaril reduced the number of tissues needed by 23 percent.