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.