Oral immunotherapy (OIT) is a treatment for food allergies that involves gradually increasing the amount of a food allergen a person eats over time. The goal is to desensitize the person to the allergen, reducing the risk of allergic reactions to accidental exposure.
Peanut OIT has been shown to be effective for children, but evidence in adults has been lacking, hence the need for additional study.
In a recent study published in the journal Allergy, researchers from King’s College London and Guy’s and St Thomas’ NHS Foundation Trust recruited 21 adults (aged 18-40) that had been diagnosed with peanut allergy.
The Process
Participants underwent double-blind placebo-controlled food challenges (DBPCFC) to peanut/placebo for confirmation of eligibility and at study exit.
Each participant began with tiny (0.8mg) doses of peanut flour administered under supervision of healthcare professionals. The doses were roughly doubled every 30 minutes to 1.5mg, then 3mg. Participants who tolerated these initial doses continued with a daily dose at home for two weeks.
Every two weeks, they returned for supervised, increasing doses, eventually reaching 1 gram (about four peanuts).
If participants could tolerate 50-100mg, they switched to actual peanuts or peanut products, starting under supervision. Once a daily dose of 1g was tolerated without reaction, participants maintained this dose or higher for four weeks and continued daily dosing at home for at least three more months.
After reaching the target dose, participants continued daily dosing at home for a minimum of three months as part of the study follow-up.
Outcome
By the conclusion of the study, 14 out of the 21 participants (67%) could tolerate eating at least five peanuts daily (1.4 grams) without a significant reaction. Importantly, 95% of the adverse reactions that occurred during the trial were classified as mild.
Conclusions
The researchers concluded that peanut OIT appears to be an efficacious treatment for adults with peanut allergy. Further studies are needed for confirmation and to characterize safety profiles in different adult subgroups.
