Optimal period for achieving sustained unresponsiveness in peanut oral immunotherapy.

BACKGROUND

Oral immunotherapy (OIT) can help children with persistent food allergies achieve sustained unresponsiveness (SU). However, the optimal therapeutic period for obtaining SU remains unclear.

OBJECTIVE

We aimed to retrospectively investigate the association between the OIT treatment period and achievement of SU.

METHODS

We enrolled patients who received OIT for peanut allergy between January 1, 2018 and December 31, 2022. OIT comprised the build-up phase, maintenance phase, complete avoidance, and an oral food challenge (OFC) for confirming SU. The peanut dose in the OFC was gradually increased to 3,000 mg (peanut protein: 795 mg), which was subsequently maintained for ≥5 months. SU was defined as a negative response to 795 mg of peanut protein after ≥2 weeks of complete avoidance. We evaluated the therapeutic OIT period for achieving SU using Kaplan-Meier analysis.

RESULTS

Forty-eight patients underwent peanut OIT. The starting age at OIT initiation was 8 (interquartile range [IQR], 7-10) years. Forty-one (85%) patients had a history of anaphylaxis. The median specific immunoglobulin E concentration to peanut and Ara h 2 at OIT initiation was 85.3 (IQR, 33.7-100) and 57.6 (IQR, 21.9-100) UA/mL, respectively. The median observational period was 2.1 (IQR, 1.6-3.0) person-years (PY). Thirty-four (71%) patients achieved SU, with the rate of SU achievement gradually increasing with the therapeutic period. The median period until SU achievement was 2.1 (95% confidence interval, 1.6-2.5) PY. The rate of SU achievement slowed down after 2.7 PY.

CONCLUSION

OIT for at least 2.7 PY can increase the rate of SU achievement. The protocol No. 3107.