ATLANTA, GA—Probiotic and Peanut Oral Immunotherapy (PPOIT) treatment appears to be associated with long-term protection from reactions and increased peanut consumption among children with peanut allergy, according to research presented at the 2017 AAAAI Annual Meeting.

“PPOIT provides long-lasting clinical benefit,” reported lead study author Kuang-Chih Hsiao, MBChB, FRACP, of the Murdoch Childrens Research Institute and The University of Melbourne, in Melbourne, Australia, and colleagues. “The majority of children who achieved sustained unresponsiveness (SU) after 18 months of treatment are still tolerating peanut symptom-free up to 5 years after treatment. PPOIT is associated with long-term suppression of allergic response to peanut.”

Long-term oral immunotherapy outcome data are relatively scant for children with peanut allergy, they noted. The team asked 48 participants in a prior PPOIT study to complete structured questionnaires on peanut intake and reactions, and to undergo a peanut skin prick test (SPT) and/or double-blind placebo-controlled food challenge involving a total of 4g peanut protein after two months without peanut exposure. 

“PPOIT-treated subjects were more likely to be eating peanuts (66.7% vs. 4.2%; risk ratio [RR] 16.0, 95% CI: 2.3–113.6; P<0.01) and tolerating a moderate/large among of peanut (52.2% vs. 4.2%; RR 12.5, 95% CI: 1.7–90.6; P=0.01) as compared to placebo-treated patients,” they reported.

Sixteen of 20 patients (80%) who received PPOIT and attained SU at the completion of treatment were still eating foods containing peanut.

“Four PPOIT-treated and 6 placebo-treated subjects reported ever having a reaction on peanut intake” not including at food challenge, after treatment was completed; none involved anaphylaxis. The study authors also reported that the mean peanut SPT wheal size in PPOIT-treated patients was 8.1mm vs. 13.3mm in patients receiving placebo (P=0.05). Additionally, 8-week SU rates at 4 year follow-up were reported as 58.3% in PPOIT-treated patients vs. 6.7% in those receiving placebo (RR 8.8, 95% CI: 1.2–64.0, P=0.03). The study authors also noted that “7 of 10 PPOIT subjects who attained SU at the end of the parent study maintained SU 4 years after completion of treatment.”

Results of this analysis support that treatment with PPOIT is effective at producing long-term clinical benefit in children with peanut allergy.