Experimental treatment may help food allergies

Food allergies are tricky business. They're on the rise in the United States and no one knows why.

Some children are allergic to many foods, and it's impossible to know based on preventive testing whether someone will have a mild or severe reaction. And so far there's no cure.

Researchers at Johns Hopkins University and Duke University are working on a treatment that may one day allow kids with allergies to safely eat the foods that cause them life-threatening reactions. It's still in the early stages, but Dr. Robert Wood of Johns Hopkins, who has been on the forefront of food allergy research, estimates the treatment could be brought to the public within six to eight years.

In his new study, researchers explored a treatment for children with cow's milk allergies. The strategy is to desensitize the child by giving small amounts of the allergen (milk). Oral immunotherapy, swallowing small amounts of the allergen, has shown to be more effective than sublingual therapy, which involves putting even tinier quantities of milk under the person's tongue.

Wood and colleagues found promising results from this small experiment with 30 children ages 6 to 18. These kids were severely allergic to cow's milk. Wood presented the study, published in the Journal of Allergy and Clinical Immunology, at the 2012 Annual Meeting of the American Academy of Allergy, Asthma & Immunology this weekend.

The results suggested that children who went through a year of sublingual therapy followed by one to two years of oral immunotherapy were less likely to have significant allergic reactions when undergoing the oral immunotherapy. Still, it did not eliminate all symptoms.

This is particularly important, because about 20% of the kids that Wood and colleagues work with have significant reactions during the treatment that make the therapy unfeasible, Wood said.

Some participants have shown they can safely eat milk products up to a year after stopping the therapies, Wood said. But only one-third have longterm protection. Others need regular exposure to milk in order to maintain protection against allergic reactions.

"With milk that’s not too hard," Wood says, because one could "eat pizza a couple of times a week."

It's not known yet whether children respond better to this kind of treatment than adults, since there have been so few participants in this research. The big barrier to broadening the scope of the research is funding, Wood said.

This is the first time the sublingual therapy has been studied in terms of its benefit as a precursor to the oral immunotherapy, Wood said.

Other research has shown that immunotherapy techniques may similarly work for children with peanut allergies. But tree nuts may be harder to treat, Wood said, because tree-nut allergic individuals often have multiple kinds of nuts they can't eat.

Researchers are separately looking at a drug called omalizumab (Xolair), approved by the U.S. Food and Drug Administration for the treatment of severe asthma, to see if it could help people with food allergies, too.

Do not try the immunotherapy technique at home; these experiments are conducted under medical supervision.