Is sublingual or oral immunotherapy better for treatment of food allergy?
Published Online: February 2012
There is currently no cure for food allergy, although recently both sublingual immunotherapy (SLIT), where the allergen is held under the tongue, and oral immunotherapy (OIT), where the allergen is simply swallowed, have shown promise as potential treatments. Which method is superior is not known. It is also not known whether the improvements in tolerance seen in other studies with immunotherapy for food allergy persist even if the food is not taken daily.
In a study in The Journal of Allergy and Clinical Immunology (JACI), Keet et al randomized 30 children with milk allergy to SLIT or SLIT followed by OIT. As has been true of other studies done thus far, the end SLIT dose was much lower than the OIT dose. Study subjects had a baseline challenge to milk, and were re-challenged after 15 months of daily maintenance therapy. If they passed the full food challenge at that time, all milk was stopped, and subjects were re-challenged one and six weeks later.
The researchers found that OIT was far more efficacious than SLIT at desensitizing to milk, with only 1/10 subjects on SLIT passing the challenge after 15 months, compared to 14/20 on OIT. However, OIT was also accompanied by more frequent serious side effects, including gastrointestinal, respiratory and multi-system reactions. After the avoidance period, 40% of subjects regained reactivity to milk on food challenge, including two subjects who lost tolerance after only one week.
The authors conclude that neither SLIT nor OIT in their current forms are optimal in terms of safety and efficacy for treatment of food allergy, although most children can be desensitized using OIT. Importantly, both researchers and patients should realize that, after 15 months of maintenance treatment, desensitization can be lost after a short period of avoidance. The authors speculate that longer periods of treatment might provide better results, but caution that most children will need to maintain the food to which they have been desensitized in their diet indefinitely.
The Journal of Allergy and Clinical Immunology (JACI) is the official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.