Xolair Relieves Kids' Seasonal Asthma Attacks: Study
Study Findings Met With Skepticism Because of Cost, Other Factors
By Kathleen Doheny
WebMD Health News
Reviewed By Laura J. Martin, MD
March 16, 2011 -- The asthma drug Xolair (omalizumab) improves asthma control, nearly eliminates seasonal flare-ups, and allows reductions in the doses of other asthma control medications in children as young as 6, according to a new study.
Xolair is approved by the FDA for use only in people 12 and older who have moderate to severe allergic asthma. In the clinical trial, Xolair was tested in children and young adults aged 6 to 20 and compared to placebo.
“We reduced symptom days by about 25%,” says researcher William W. Busse, MD, professor of medicine at the University of Wisconsin School of Medicine and Public Health, Madison. "And we reduced exacerbation rates [the number of attacks] by about 30%.''
As good as he says those results are, Busse says, ''that wasn't the important part." His team found that the spike in asthma attacks typically seen in the fall and linked with colds and other airway infections was virtually eliminated in the children taking Xolair. "It indicates in these kids that allergy seems to play an important role in their asthma," he tells WebMD.
Another expert who reviewed the study, however, is not convinced that the drug merits more widespread use. Zab Mosenifar, MD, a pulmonologist who is executive vice chair of the department of medicine and a professor of medicine at Cedars-Sinai Medical Center in Los Angeles, balks at the cost, among other factors.
According to the manufacturer, Genentech, the typical cost for the injected drug is $1,700 a month.
"Industry has been looking for a means of expanding the use of this agent," says Mosenifar, noting that its use is not widespread in patients 12 and older, by his observations.
Asthma Drug Xolair: Background
Xolair is a biologic drug that works by blocking antibodies called IgE, which in excess can trigger symptoms of allergic asthma, including shortness of breath, coughing, and wheezing.
Four years after its approval in 2003, the FDA required Genentech Inc. (which now markets the drug together with Novartis) to add to the label a boxed warning -- commonly called a ''black box" warning -- to caution users that the drug may cause anaphylaxis. That's a serious condition in which a person has trouble breathing, the chest becomes tight, and the throat and mouth swell.
In clinical trials, about one in 1,000 people reported anaphylaxis. Malignances have been another issue. In clinical trials, 0.5% of people on the drug reported cancers of the skin, breast, and other sites, compared to 0.2% of people on placebo.
In 2009, the FDA began to evaluate findings from an ongoing study of Xolair that suggests a link with heart disease and cerebrovascular problems, although it has not yet suggested any changes based on the interim findings.
Xolair: Study Details
Busse, with his co-researchers from the Inner City Asthma Consortium, randomly assigned 419 children and young adults, aged 6 to 20, with allergic asthma to get either injections of the drug or placebo. At the time of assignment to the groups, 73% had either moderate or severe disease.
About 97% of both groups were either African-American or Hispanic.
Busse tells WebMD it's long been known that inner-city children with asthma often have more severe disease than children living outside of urban areas, and they often have co-existing allergies to dust mites, cockroaches, and other allergens.
Both groups got education about controlling these environmental allergens and were given bedding covers, pest traps, and a vacuum cleaner.
Research has shown that hospitalization rates go up about two weeks after children with allergic asthma return to school in the fall, as they catch respiratory infections, triggering worse asthma attacks, Busse says.
In the study, the researchers followed the participants for 60 weeks, evaluating whether the drug reduced symptoms of asthma.
Before the study started, Busse says, the children's asthma was controlled with a variety of other medications, and then Xolair was added on.
Children got the injections either every two weeks or every four weeks, for a total of either 15 or 30 injections.
Besides the reduction in symptom days and attacks, children on the drug were less likely to be hospitalized. Although 1.5% of children on the drug were hospitalized during the study, 6.3% of children in the placebo group were.
Overall, adverse events affected the placebo group more. One in the Xolair group and six in the placebo group had anaphylaxis.
The typical seasonal spike in asthma wasn't seen in the drug group in the fall and summer, but nearly doubled in the placebo group during those times.
The study results suggest that in these children allergy plays an important role in their asthma, Busse says, with an interaction between allergy and viral infections possibly triggering the asthma attacks, a link others have suggested.
Controlling the allergies, Busse says, didn't result in fewer colds, but in his study did result in fewer asthma attacks. "We don't know exactly why," he says, although reducing inflammation may help explain the findings.
Although the drug is expensive, Busse points to the reduction in hospitalization costs as a benefit.
The study was funded by the National Institute of Allergy and Infectious Diseases of the National Institutes of Health and by Novartis.
Busse reports receiving board membership fees from Centocor and Merck, consulting fees from Genentech, and consulting fees and grant support from Novartis and other pharmaceutical companies.
Asthma Drug Xolair: Second View
Mosenifar reviewed the study for WebMD but was not involved in it. He has no disclosures relevant to the topic.
Although the study is scientifically sound, he says, "I'm a little skeptical about this. This drug has been around for seven or eight years.'' He cites concerns about anaphylaxis, cancers, and expense.
"Certainly this drug plays a role in allergic asthma, that is not new," he tells WebMD. "The nuance in this is that the allergy component is diminished [with Xolair]."
Although the population studied is definitely at higher risk of allergy and asthma, Mosenifar says ''there are better ways of dealing with this issue -- and that is environmental cleaning and household cleaning, which the authors imply have limitations. But I think they are very important."
As an alternative, he would suggest spending the money on basic measures -- dust mite-resistant pillow cases and control of pests such as cockroaches -- with the goal of preventing the initial elevation of IgE antibodies that sets the allergic ''cascade'' into action.
Busse, W. The New England Journal of Medicine, March 17, 2011, vol 364: pp 1005-1015.
William Busse, MD, professor of medicine, University of Wisconsin School of Medicine and Public Health, Madison.
Christopher Vancheri, spokesman, Genentech Inc., Nutley, N.J.
Zab Mosenifar, MD, pulmonologist, professor of medicine, executive vice-chair, department of medicine, Cedars-Sinai Medical Center, Los Angeles.
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