Peanut Oral Immunotherapy With or Without H1 and H2 Antihistamine Premedication for Peanut Allergy (PISCES): A Placebo-Controlled Randomized Clinical Trial.

BACKGROUND: Current forms of peanut oral immunotherapy (OIT) are associated with side effects, and there is a lack of evidence addressing how to mitigate them. OBJECTIVE: To determine whether premedication with desloratadine and ranitidine results in fewer side effects during peanut OIT/desensitization. METHODS: A total of 43 patients with peanut allergy (mean age, 7.6 ± 2.1 years, 37% females, 63% males, baseline eliciting dose, 33 ± 26 mg) were randomized to OIT with or without concomitant H1 and H2 antihistamine blockade, or double-placebo. 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. RESULTS: Adverse reactions occurred more in the OIT groups compared with the double-placebo group (OIT with antihistamines vs double-placebo hazard ratio, 3.75 [95% CI, 2.79-4.72]; OIT with placebo antihistamines vs double-placebo, hazard ratio, 4.62 [95% CI, 3.61-5.62]). Patients given antihistamines cotreatment with OIT had a similar risk of adverse events compared with those who did not use antihistamines with OIT (hazard ratio, 1.23 [95% CI, 0.49-1.97]). OIT with and without antihistamines accelerated the incidence rate of adverse events compared with double-placebo (4.8 and 6.4 events per patient vs 3.5 per patient, incidence rate ratio, 2.49 [95% CI, 1.36-4.56] and 2.04 [95% CI, 1.01-4.15], respectively). Antihistamines pretreatment modestly reduced the frequency of moderate to severe adverse reactions among OIT-treated groups (1.9 per patient vs 4.2 per patient, incidence rate ratio, 0.46 [95% CI, 0.24-0.89]), primarily urticaria (0.6 vs 2.1 per patient) followed by abdominal pain (2.6 vs 4.2 per patient), but increased neuropsychiatric adverse events (primarily tiredness and sedation, 2.3 vs 0.7 per patient). Eliciting doses after treatment were similar in all groups. Quality of life improved similarly regardless of treatment with peanut OIT or placebo OIT. CONCLUSIONS: Peanut OIT with antihistamines modestly reduce the skin and gastrointestinal components of the high incidence of adverse reactions during OIT, and there are no clear differences in improvement in quality of life whether treated with OIT, OIT with antihistamines, or placebo OIT despite OIT being effective in inducing desensitization. Safer food allergy treatment approaches that importantly improve quality of life need to be proved in future robust randomized trials.

Prediction of clinical peanut allergy status among children in Hamilton, Ontario using chart review data collected during 2012-2015.

BACKGROUND: Peanut sensitization does not necessarily indicate clinical peanut allergy, and uncertainty as to whether or not there is true peanut allergy can lead to increased anxiety and decreased quality of life for patients and their families. The gold standard for diagnosing clinical peanut allergy is the oral food challenge, but this method is time-consuming and can cause severe allergic reactions. It would therefore be beneficial to develop a tool for predicting clinical peanut allergy in peanut-sensitized individuals whose peanut allergy status is unknown so as to better determine who requires an oral food challenge for diagnosis. METHODS: Two separate studies were conducted. In Study 1, we recruited 100 participants from the allergy clinic at McMaster University and community allergy outpatient clinics in the greater Hamilton area. We examined 18 different variables from participants and used univariate and multivariable logistic regression analysis to determine how well these variables, singly and in combination, were able to predict clinical peanut allergy status. In Study 2, we conducted a retrospective chart review of a second cohort of 194 participants to investigate the reproducibility of our findings. This was a matched case-control study where 97 peanut-allergic participants were gender- and age-matched to 97 non-allergic control participants. RESULTS: Peanut skin prick test wheal size was the best predictor of clinical peanut allergy in both study cohorts. For every 1 mm increase in wheal size, the odds ratio of an individual having clinical peanut allergy was 2.36 in our first cohort and 4.85 in our second cohort. No other variable approached the predictive power of wheal size. CONCLUSIONS: Peanut skin prick test wheal size is a robust predictor of clinical peanut reactivity. The findings of this study may be useful in guiding clinician decision-making regarding peanut allergy diagnostics.