Oral therapy for cow’s milk allergy may show better adherence than in other allergens

Key takeaways:

• Patients with cow’s milk allergies experienced the most allergic reactions but also the highest rate of adherence to OIT.
• Patients with a sesame and peanut allergy had the lowest rate of unlimited consumption.

Participants with an allergy to cow’s milk had the lowest rate of oral immunotherapy treatment discontinuation, according to a study published in Annals of Allergy, Asthma and Immunology.

The study aimed to evaluate and compare the safety and adherence of oral immunotherapy in patients with a food allergy to milk, peanuts, tree nuts, sesame or egg at the maintenance dose phase of the study, Meital Almog, MD, of the division of allergy and clinical immunology, Bnai Zion Medical Center, Rappaport Faculty of Medicine, Technion Haifa, Israel, and colleagues wrote.

Questionnaires were sent to caregivers of 256 patients receiving OIT between June 2019 and August 2022. Among them, 213 patients (mean age, 10.05 years; 54% boys) were included in the final analysis.

The questionnaire comprised 13 items and asked about tolerated food allergens during the maintenance phase. Items included frequence of consumption, incorporation of the allergen into their diet, symptoms after consumption of the allergen, medication use and if the allergen was avoided.

Participants were asked to consume daily maintenance doses of the allergens: 4,500 mg (150 mL) of cow’s milk, 1,200 mg (4U) of peanut protein, 4U of cashew, 8U of hazelnut, 1U of walnut, a teaspoon of tahini (sesame) and 3,250 mg (half an omelet) of egg protein.

Lengths of maintenance doses differed, including 3 to 6 months (n = 19), 6 to 12 months (n = 47), 1 to 2 years (n = 75) and more than 2 years (n = 71), with a median follow-up length of 19.4 months.

Among the 213 participants, 101 (47%) experienced a food-related allergic reaction while on the maintenance dose, with 60% requiring treatment, including 4.2% with an epinephrine autoinjector.

Authors compared the odds of allergic reaction of each allergen group with the group with the highest reaction rate, which was cow’s milk allergy (CMA). They found significant decreases in reactions of patients with a sesame allergy (72%; OR = 0.28; 95% CI, 0.11-0.71), peanut allergy (72%; OR = 0.28; 95% CI, 0.12-0.63) and tree nut allergy (67%; OR = 0.33; 95% CI, 0.15-0.74).

OIT treatment was stopped by 15 (7.5%) patients. Those with a sesame allergy were 10 times more likely to be at risk for stopping OIT treatment than patients with CMA (OR = 10.7; 95% CI, 1.06-95.79).

When evaluating the correlation between epinephrine use and OIT discontinuation adjusted for atopic dermatitis, patients who used injectors had a 6.5% higher risk for stopping OIT (OR = 6.5; 95% CI, 0.85-36.13).

The odds ratio for unlimited allergen consumption was the highest in the CMA group. Patients with a peanut allergy showed an 88% less probability of unlimited consumption compared with the CMA group (OR = 0.12; 95% CI, 0.03-0.36). Sesame allergy had a 78% less probability (OR = 0.22; 95% CI, 0.06-0.7), and patients with tree nut allergy had a 72% less probability (OR = 0.28; 95% CI 0.1-0.73).

The study dropout rate was highest among those with a sesame allergy compared with the CMA group (OR = 10.7; 95% CI, 1.06-95.79).

The authors highlighted that this study shows that OIT is a feasible treatment in daily life, as more than 90% of participants continued OIT at their MD throughout the study period. They also emphasized that the low rate of unlimited consumption in the sesame and peanut allergy groups as well as their relatively high dropout rate support the overall benefits of using low-dose OIT, but further studies are needed to confirm these findings.