In the current trial, researchers reported interim results of a study that enrolled 40 teenage and adult patients with moderate, but not severe, reactions to peanuts. They divided them evenly into groups receiving either peanut protein or a placebo. The participants took the drops daily at home, coming into National Jewish Health and other academic medical centers for increased doses. Patients will continue immunotherapy for approximately three years.
After 44 weeks, 70 percent of the participants receiving peanut immunotherapy increased the average amount of peanut protein they could safely consume from 3.5 milligrams to 496 milligrams. After 68 weeks, responders were desensitized further, safely consuming, on average, 996 milligrams of peanut protein. That level of desensitization could help protect against an accidental ingestion, which averages about 100 milligrams. One peanut contains on average about 250 milligrams of peanut protein.
"We are hopeful that continued immunotherapy will help more patients become less sensitive to peanuts," said Dr. Fleischer.
Even at relatively low doses, participants frequently experienced some symptoms, most commonly itching in the mouth and throat. One patient developed very itchy red skin and more serious symptoms in the mouth after a daily dose at home. The patient required an antihistamine, an epinephrine injection and close observation at one of the research centers.
"This is an experimental treatment, promising, but with potentially serious side effects," said Dr. Fleischer. "Some physicians are treating their peanut-allergic patients with immunotherapy outside of carefully controlled and observed trials. I don't think that approach is safe until we better understand how much protein to deliver, through what method, and to which patients."
|Contact: William Allstetter|
National Jewish Health