Epicutaneous immunotherapy for treatment of peanut allergy: Follow-up from the Consortium for Food Allergy Research

Abstract

Background: Consortium for Food Allergy Research investigators previously reported 52-week outcomes from a randomized controlled trial of peanut epicutaneous immunotherapy, observing modest and statistically significant induction of desensitization, highest in children ages 4 to 11 years.

Objective: We sought to evaluate changes in efficacy, safety, and mechanistic parameters following extended open-label peanut epicutaneous immunotherapy.

Methods: Peanut-allergic participants (4-25 years) received 52 weeks of placebo (PLB), Viaskin Peanut 100 μg (VP100) or 250 μg (VP250), and then crossed over to VP250 for PLB (PLB-VP250) and VP100 (VP100-VP250) participants and continued treatment for VP250 participants (total = 130 weeks of active epicutaneous immunotherapy). Efficacy was assessed by double-blind, placebo-controlled food challenge (5044 mg peanut protein), and adherence, safety, and mechanistic parameters were evaluated.

Results: At week 130, desensitization success was achieved in 1 of 20 (5%) PLB-VP250, 5 of 24 (20.8%) VP100-VP250, and 9 of 25 (36%) VP250 participants, with median successfully consumed dose change from baseline of 11.5 mg, 141.5 mg, and 400 mg, respectively. Median age (years) for week 130 desensitization success was 6.2 years (interquartile range, 5.2-9.1) versus 9.4 years (interquartile range, 7.6-12.8) for failures (P < .001). Adherence was 96%. Adverse reactions were predominantly local patch-site reactions. Significant increases in peanut- and Ara h2-specific IgG4 observed at week 52 persisted to week 130. By a post hoc analysis, there were no statistically significant increases from week 52 to week 130 in either desensitization success or successfully consumed dose.

Conclusions: Extended treatment with VP250 was well tolerated, and desensitization observed at week 52 persisted between weeks 52 and 130. Treatment success was observed predominantly in younger participants, with younger age at initiation of active therapy an important predictor of success.

Trial registration: ClinicalTrials.gov NCT01904604.

Keywords: IgE; IgG(4); Peanut allergy; desensitization; epicutaneous immunotherapy; follow-up; food allergy.

Copyright © 2020 American Academy of Allergy, Asthma & Immunology. All rights reserved.

Figures

FIG 1.

A, SCD from baseline to week 130 oral food challenge by treatment group in all participants. B, SCD at week 52 (x-axis) vs week 130 (y-axis) by treatment group and desensitization success and failure. Values to the left of the diagonal line represent participants whose SCD at week 130 is higher than at week 52. C, SCD at week 130 by age at start of therapy and desensitization success and failure (dashed lines indicate ages 7 [lower line] and 12 years [upper line]). For PLB-VP250 participants, the week 52 DBPCFC following PLB therapy was used as baseline.

FIG 2.

Immune mechanistic parameters from baseline through week 130 by treatment group. A, Peanut-specific IgE. At week 52, the PLB-VP250 group had higher values compared with VP100-VP250 (P = .001) and VP250 (P = .008) groups; at week 130, the VP250 group had higher values compared with PLB-VP250 (P = .002) and VP100–VP250 (P = .008) groups. B, Ara h2 IgE. C, Peanut IgG4. D, Ara h2 IgG4. Overall, the VP250 group had higher values compared with the PLB-VP250 group (P = .005); the VP250 group also had higher values when compared with the VP100–VP250 group (P = .002). A solid black line represents the median, and blue hatched lines represent the upper and lower quartiles. kUA/L, Kilounits of antibody per liter.

FIG 3.

Effect of peanut EPIT on basophil activation (measured by percent CD63+ basophils) over time by treatment group. Top row, PLB-VP250 group; middle row, VP100-VP250 group; bottom row, VP250 group. Cells were stimulated with 0.1 μg/mL peanut extract (column 1) and 0.01 μg/mL peanut extract (column 2). A decrease in the percentage of CD63+ basophils over time was observed only following stimulation with 0.01 μg/mL peanut extract, and statistically significant differences between treatment groups over time were not observed. These are box plots, with the lines inside each box representing the median and the diamonds representing the mean.