Long-term Outcome of Peanut Oral Immunotherapy Facilitated Initially by Omalizumab

Publication date: Available online 26 September 2018

Source: The Journal of Allergy and Clinical Immunology: In Practice

Author(s): Christina S.K. Yee, Sultan Albuhairi, Elizabeth Noh, Kristel El-Khoury, Shervin Rezaei, Azza Abdel-Gadir, Dale T. Umetsu, Elizabeth Burke-Roberts, Jennifer LeBovidge, Lynda Schneider, Rima Rachid

Abstract

Background

We successfully used omalizumab to faciliate peanut oral immunotherapy (OIT) in children with reactivity to ≤50mg peanut protein and with high peanut-IgE (median 229 kU/L).

Objective

We report on long-term OIT outcomes in these patients, including dosing changes, adverse events, peanut immunoglobulin changes and quality of life (QoL).

Methods

Patients were followed for up to 72 months (67 months maintenance). Outcomes were collected on peanut dose amount, form and frequency, as well as adverse events, (QoL), and laboratory studies.

Results

Of 13 patients initially enrolled, 7 patients (54%) continued on peanut OIT through month 72; 6 (46%) discontinued therapy because of adverse reactions. Maintenance peanut protein dose varied between 500-3,500mg. Most patients consumed different peanut-containing products. All patients experienced at least one adverse event, and one patient developed eosinophilic eosphagitis. Peanut- IgE, Arah1-IgE and Arah2-IgE, peanut-SPT, Peanut-IgE:IgE ratio, and Arah2-IgE:Arah2-IgG4 ratio decreased on OIT. Peanut-IgG4, Arah1-IgG4, Arah2-IgG4 initially increased on OIT then decreased, though not falling to baseline levels. In patients who stopped OIT, there was a trend for reversal of these biomarker changes. Higher peanut-IgE and Arah2-IgE at study month 12 was associated with discontinuation. Patient and parent QoL improved from baseline, even in patients who discontinued OIT.

Conclusion

While adjunctive omalizumab allowed for faster and successful desensitization in patients with high peanut-IgE, almost half of patients discontinued OIT within 72 months because of reactions. Patients who stopped therapy had higher month 12 peanut-IgE and Arah2-IgE. It is possible that these patients might benefit from longer omalizumab administration.