New Drug Prevent, Treats Flu

CHICAGO, July 6 (UPI) -- A new kind of drug has been shown to be effective in preventing, as well as in treating, the flu, say scientists.

Called Relenza, the drug could cut short dangerous flu outbreaks in nursing homes and the annual bouts on cruise ships in Alaska and the Yukon Territory, that sickened about 40,000 tourists and tourism workers last year and has stricken more than 532 so far this season.

Researcher Arnold S. Monto says, ''I'm sure they wish they had Relenza right now.''

Monto is the lead author of a new study on the drug and a professor of public health at the University of Michigan in Ann Arbor.

The study was funded by Glaxo Wellcome Inc., which is currently seeking U.S. Food & Drug Administration approval for Relenza for treating flu. Glaxo has not yet submitted an application for use of the drug in preventing flu, but it is hoping to do so later in the year.

Monto says this drug and others from a new class of compounds called neuraminidase inhibitors have significant advantages over currently available treatments for flu -- amantadine and rimantadine.

Monto says, ''This study is the first to report the efficacy of a neuraminidase inhibitor in preventing influenza infection and illness.''

These drugs only attack type A flu, while the neuraminidase inhibitors work against both types A and B.

Another advantage is that it does not promote the development of resistant strains of the virus, say the scientists.

Also, the currently approved drugs have side effects, such as nervousness, insomnia and dizziness, that have not been seen in studies on Relenza.

''We have not had a new flu antiviral for 30 years,'' Monto told UPI in a phone interview from Birmingham, England, where he was delivering another report on the use of the drug in treating flu.

The current study of 1,100 volunteers showed that taking the drug once a day reduced the risk of getting the flu by nearly 70 percent, and reduced the chances of getting flu with fever by more than 80 percent. The volunteers took drug or placebo for a month.

The study is published in Wednesday's issue of the Journal of the American Medical Association.

Relenza and other drugs in the new class known as neuraminidase inhibitors, suppresses a flu enzyme that allows the disease-causing virus to spread in a person's body.

He adds that the ''best defense'' against flu is vaccination, but many people do not get vaccinated, and sometimes the vaccine does not protect against strains of the virus that are common during a specific season. This happened in 1997-1998 season, when ''a change in the circulating virus limited the efficacy of the vaccine.''

In February, the company failed to win a thumbs up from an advisory panel to the FDA because of questions about the statistical significance of studies submitted for approval.

Since then, Glaxo Wellcome, which licensed the drug from Australia's Biota Holding Ltd., has been working with the FDA and is hoping for approval for treatment of flu in time for the next flu season.

The drug has been cleared for treatment of flu by the European Union and in Australia.

Relenza was created through a method in which computers were used in designing a drug tailored to fit into a molecule specific to the flu virus, says Michael Ossi, director of clinical development for infectious diseases and hepatitis for Glaxo Wellcome.

The drug, a dry powder, is delivered through an inhaler, that has been described as looking like a ''little Starship Enterprise,'' Ossi says.

A similar drug, an oral neuraminidase inhibitor, is under development by Hoffmann-LaRoche.

Scientists say about 30 million Americans get flu each year, and about 20,000 die from it. The annual economic losses from the disease have been estimated at as much as $5 billion.

In an editorial accompanying the study, Dr. Peter A. Patriarca of the U.S. Food & Drug Administration, Bethesda, Md., says, ''looming in the future is the next pandemic of influenza, which, depending on the virulence and penetrance of the infection, could result in as many as 200,000 excess deaths and economic losses in excess of $160 billion.'' (Written by Mara Bovsun in New York City) Copyright 1999 by United Press International All rights reserved