Oral immunotherapy (OIT) is not made more effective when patients take the drug omalizumab in conjunction with the treatment, researchers say in a new study. However, the drug, which also goes by the brand name Xolair, did significantly reduce the risk of having an adverse allergic reaction during cow’s milk OIT treatment, which study authors found to be a promising development.
“We didn’t see a difference in the rate of desensitization or sustained tolerance,” says Dr. Hugh Sampson, director of the Jaffe Food Allergy Institute at New York’s Icahn School of Medicine at Mount Sinai. But while effectiveness wasn’t improved, the group taking omalizumab did have significantly fewer adverse reactions during OIT, says Sampson.
In the trial of 57 kids, half were given injections of omalizumab before and during the oral immunotherapy, while the other half were given a placebo.
“The patients who were on omalizumab experienced a little less than a third of the number of reactions than the people on the placebo, both in the build-up phase and during long-term maintenance,” he says.
Sampson notes that in the build-up phase, there was only one incidence of needing epinephrine in the patients taking omalizumab, while there were 8 in the placebo group. While that’s an encouraging figure, Sampson points out that this also shows that omalizumab doesn’t prevent all adverse reactions. In the placebo group, the most common reactions were itching in the mouth and throat, a sensation of swelling in the tongue or lips and more serious reactions like severe abdominal cramping, hives and wheezing.
Sampson says that the reduction in adverse reactions with omalizumab would probably hold true with other OIT, and that the study shows omalizumab does make OIT safer.
Because omalizumab is expensive, Sampson wonders if there’s a way to figure out who would benefit from it most, and target those people.
“If we’re going to use OIT as a therapy for treating food allergies, it would be nice to have omalizumab available, especially for high risk patients,” says Sampson.