Study: Drug May Help Stubborn Asthma

Friday, September 1st 2000, 12:00 am
By: News On 6

FLORENCE, Italy (AP) — A study suggests that an experimental drug could halve the number of asthma attacks suffered by people whose condition isn't well controlled with current treatment — about 15 percent of all asthma patients, a researcher said Thursday.

The first major study of the injectable drug, presented Thursday at the World Congress on Lung Health, also found that it allowed half of patients to stop using steroid inhalers and the rest to reduce their dependence on them, said Dr. Stephen Holgate, who led the study.

Steroids have been linked to dangerous side effects, such as osteoporosis and stunted growth in children.

The medication, Xolair, acts earlier in the cascade of reactions that lead to an asthma attack than other treatments, said Holgate, an asthma researcher with the Medical Research Council in London and a professor at England's Southampton University.

``This discovery is really the first major step forward in the treatment of asthma that we've had in the last 20 years,'' he said.

Those taking the drug had half the number of asthma attacks as subjects who did not receive it. Their lungs functioned better and they were less often admitted to the hospital with asthma attacks. Some of the patients started improving two weeks into the 18-month study, and no serious side effects were reported, according to the researchers.

The results of the study were presented at a session sponsored by one of the drug's makers, Novartis AG of Switzerland.

``It's an excellent result,'' said Dr. Mitchell Friedman, head of the lung center at Tulane University in New Orleans, who was not connected with the research. ``It may transform asthma treatment, certainly in allergic asthma, but there are a whole lot of things that influence inflammation in asthma. Whether this will be the major one remains to be seen.''

Xolair is the first in a new class of drugs that target a chemical in the blood, called IgE, that is involved early in the string of events that lead to the development of asthma.

Asthma — a respiratory condition that afflicts about 150 million people worldwide — is caused when irritants prompt the airways to narrow. About 80 percent of asthma cases are brought on by allergic reactions.

When people breathe in substances they are allergic to, IgE is released into the blood and attaches itself to cells lining the respiratory tract on structures called receptors, triggering allergic reactions that lead to asthma.

Holgate said that the drug, genetically engineered using mouse genes grafted onto a human antibody, blocks the ability of IgE to trigger inflammation by introducing a substance that binds with it before it has a chance to attach to the cells in the airway.

When the influence of IgE is eliminated, the number of receptors linked to it also drop by about 1,000 times, Holgate said.

The study involved 1,300 people, including 300 children, who had moderate or severe asthma. They were all taking inhaled steroids.

For the first four months of the study, in addition to a fixed dose of steroids, half the group got the new drug and half got a fake one. In the second three months, the scientists tapered the dose of steroids, where possible.

Overall, 19 patients taking the fake drug were admitted to hospital with an asthma attack, compared with two patients taking Xolair.

``There are substantial improvements in the quality of life in these people taking steroids,'' Holgate said.

So far, there is no evidence that IgE performs any other function in the body, but the drug's makers are continuing to study that possibility in case the treatment knocks out any positive role IgE may have.

The drug, whose chemical name is omalizumab, is being developed jointly by Novartis AG, Genentech, Inc. and Tanox Inc. Approval to market the drug is pending in several countries.