Quote
Oral immunotherapy for food allergy is currently under active investigation, and its use in clinical practice is spreading despite the paucity of data on long-term outcomes. In this month's Journal of Allergy and Clinical Immunology, Keet et al., report on long-term follow-up data from two studies of oral immunotherapy for milk allergy. Both studies enrolled children 6-18 years old with food-challenge proven milk allergy and treated children with escalating doses of cow's milk powder. The authors collected follow-up data by standardized questionnaire and/or clinical follow-up at a median of 4.5 years after the completion of dose escalation for the first study and 3.2 years for the second study.
All 32 children treated at Johns Hopkins in these studies (16 from each study) had some follow-up data. Surprisingly, after several years, only 31% of subjects were tolerating at least full servings of cow's milk with minimal or no symptoms, and 19% reported anaphylaxis at least once in recent follow-up. Twenty-two percent of subjects were consuming no or only trace amounts of milk. Several baseline and early treatment characteristics were associated with poorer long-term outcomes, including baseline milk specific IgE and higher rates of lower respiratory and gastrointestinal symptoms with dose escalation.
The authors' findings suggest that long-term outcomes following milk oral immunotherapy are mixed, and that some subjects lose the initial beneficial effects of desensitization over time. These findings call for more research into long-term outcomes of immunotherapy for food allergy. Overall, although only representing a small number of subjects, these results suggest that caution is warranted in bringing oral immunotherapy to widespread clinical use.