Multi-allergen oral immunotherapy may save time, but increases epinephrine use

LOUISVILLE, Ky. — Multi-allergen oral immunotherapy may reduce treatment time overall but also led to significant increases in epinephrine use compared with single-allergen oral immunotherapy, according to study results.

“Multiple studies have shown oral immunotherapy ... a food allergen desensitization process, to be effective and improve the quality of life for food-allergic patients,” E. Katherine Larson, MS, MAT, PA-C, a physician assistant at Aspire Allergy & Sinus, said during her presentation at the American College of Allergy, Asthma & Immunology Annual Scientific Meeting. “However, there is a paucity of data concerning multi-allergen OIT where patients treat multiple allergens concurrently.”

Larson and colleagues conducted a study that involved 169 patients using single-allergen OIT and 147 using multi-allergen OIT.

A greater proportion of the multi-allergen cohort compared with the single-allergen group had multiple food allergies (100% vs. 45.6%; P < .001), a history of asthma (44.2% vs. 33.1% P = .043), history of allergic rhinitis (69.4% vs. 55.6%; P = .012), and a history of reaction to one of the treatment foods (95.2% vs. 88.8%; P < .05).

Mean baseline specific IgE totals included 49.76 kU/L for the multi-allergen cohort and 37.86 kU/L for the single-allergen cohort (P = .003), which the researchers called a statistically significant difference as well.

According to the researchers, 85.2% of those in the single-allergen cohort and 80.3% of those in the multi-allergen cohort completed their OIT, which did not represent any statistical difference.

“However, there was a statistical difference in epinephrine use rates between the two cohorts, with a 6.5% epinephrine use rate in the single-allergen cohort vs. 15.7% in the multi-allergen cohort,” Larson said (P = .009).

There also was a statistical difference in mean days to completion between the groups, with the single-allergen cohort taking 290 days and the multi-allergen cohort taking 311 (P < .001).

“However, multi-allergen OIT still results in an overall time reduction compared to single-allergen OIT due to avoidance of multiple rounds of treatment,” Larson said.

Using three logistic regression models, the researchers compared epinephrine use between the cohorts. In the first model, which did not control for other differences between the groups, patients in the multi-allergen cohort were 2.66 times (95% CI, 1.25-5.67) more likely to use epinephrine than those in the single-allergen cohort.

The second model, which used comorbidity controls, found that the multi-allergen cohort was 2.21 times (95% CI, 0.79-6.19) more likely to use epinephrine. The third model added baseline testing and reaction history controls (OR = 1.63; 95% CI, 0.55-4.82).

“The odds ratio drops to 1.63 in model three, and the difference in epinephrine use rates between the cohorts is no longer statistically significant,” Larson said.

Larson noted that the study’s limitations included its small sample size, the significant differences between cohorts and its clinical nature, which reduced standardization of its protocol.

“A randomized controlled trial would solve many of the issues concerning this study,” Larson said, adding that clinicians can still conclude that multi-allergen OIT is as effective as single-allergen OIT while saving treatment time overall.

“However, clinicians should approach multi-allergen OIT using shared decision-making with patients, highlighting the possibility of increased epinephrine use with multi-allergen OIT,” she said.