PTAH presents low eosinophilic esophagitis risks for peanut allergy patients

Approximately 1% of patients on peanut allergen powder oral immunotherapy developed eosinophilic esophagitis, according to a study published in The Journal of Allergy and Clinical Immunology: In Practice.

Patients treated for milk, egg and peanut allergy with oral immunotherapy (OIT) have reported eosinophilic esophagitis (EoE), Caroline Nilsson, MD, PhD, of the Karolinska Institutet in Solna, Sweden, and colleagues wrote.

But for patients with a history of EoE, peanut (arachis hypogaea) allergen powder (PTAH) (Palforzia, Aimmune Therapeutics) is contraindicated. Per the product label, PTAH should be discontinued if EoE develops during treatment.

The study included two phase 2 trials and six phase 3 trials comprising 1,217 participants aged 4 to 55 years who received PTAH. Due to gastrointestinal symptoms, 62 patients withdrew from the study.

Also, 17 of 28 patients who were referred for gastroenterology evaluation underwent esophagogastroduodenoscopy. Twelve were diagnosed with EoE, resulting in the researchers’ EoE incidence finding of approximately 1%.

The EoE cases included one woman, aged 33, and nine boys and two girls aged 4 to 17. The most common comorbid atopic diseases were asthma (n = 11), allergic rhinitis (n = 10), other food allergies (n = 9) and atopic dermatitis (n = 5).

Globus sensation, gastroesophageal reflux, regurgitation, vomiting and postprandial abdominal pain were among the common presenting symptoms, which improved or resolved within 12 days to 12 months of PTAH discontinuation and standard-of-care EoE therapy initiation in 11 cases. The 12th case resolved after 12 months.

The researchers considered 10 of these cases related to PTAH treatment, as four of these patients had a history of chronic or recurrent GI symptoms. Two cases were considered unrelated, since GI symptoms may have been present before the start of PTAH. The researchers classified three cases as mild, seven as moderate and two as severe, with none considered serious.

Each participant received medication for symptoms, and 10 were treated with a proton pump inhibitor with or without a topical corticosteroid (fluticasone and/or budesonide, n = 4). Only one participant continued PTAH treatment after EoE was diagnosed.

The researchers noted that their approximately 1% overall EoE incidence was lower than a previously reported 2.7% rate in a meta-analysis and a 5.1% rate in a retrospective review. They also said their findings demonstrated that most EoE associated with OIT resolves during maintenance OIT and has no associations with clinical symptoms.

But the researchers cautioned that their limited analysis, based on multiple clinical trials, cannot provide the same quality of evidence as a true longitudinal study. They also said their exclusion criteria may have influenced the low rate of EoE in their analysis, among other limitations.