Can antihistamines mitigate adverse reactions in peanut oral immunotherapy?
Published: May 24, 2022
Peanut allergy is a growing global problem, but current forms of treatment using oral immunotherapy (OIT) are associated with side effects and there is a lack of evidence addressing how to mitigate them.
Published in The Journal of Allergy and Clinical Immunology: In Practice, Dr. Chu and colleagues from McMaster University report the Peanut Immunotherapy Starting in Canada, Evaluation and DiScovery (PISCES) 3-arm, parallel-design, placebo-controlled randomized trial comparing peanut OIT with or without concomitant use of second-generation H1 antihistamines (desloratadine) and H2 blockers (ranitidine) to placebo OIT.
Participants aged 5 to 10 years were treated for 12 months. Patients, study staff/investigators, and statisticians were blinded. The primary outcomes were the frequency and severity of OIT-induced adverse events. The secondary outcomes were quality of life and eliciting doses to blinded food challenge. The study funders (Allergy, Genes and Environment Networks of Centres of Excellence [AllerGen NCE], Canadian Allergy, Asthma, and Immunology Foundation, Canadian Society for Allergy and Clinical Immunology, Hamilton Health Sciences, McMaster University, Food Allergy Canada, and the Delaney Family) had no role in study design, collection, analysis, interpretation of data, writing of the report, or decision to submit the article for publication.
Among the 43 participants treated, peanut OIT, compared to placebo OIT, caused a high rate of adverse reactions that were modestly mitigated (primarily moderate-severe urticaria [hives] and abdominal pain) by the addition of antihistamines. Quality of life improved similarly regardless of treatment with peanut OIT or placebo OIT. The addition of antihistamines to OIT, however, increased neuropsychiatric events, most commonly tiredness and sedation. Both peanut OIT groups increased their eliciting doses to in-clinic food challenges after treatment. This is the first randomized trial showing that although antihistamines are a low-cost option that can be added to OIT, choosing to do so must be balanced against their modest benefits and added adverse effects. Safer food allergy treatments that importantly improve patient and family quality of life need to be proven in future randomized controlled trials.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.