Continued treatment enhances effect of epicutaneous immunotherapy for peanut allergy
Click Here to Manage Email Alerts
Key takeaways:
- 12 more months using an immunotherapy skin patch for peanut allergy increased the response rate.
- Placebo participants who crossed over to treatment showed similar responses to the original treatment cohort.
ANAHEIM, Calif. — An additional 12 months of treatment with a skin patch-based approach to immunotherapy for peanut allergy increased the percentage of toddlers able to tolerate peanut, according to results of the EPOPEX study.
This interim analysis of the open-label extension to the EPITOPE study evaluating the efficacy of VP250 (Viaskin Peanut, DBV Technologies) was presented as a late-breaking abstract at the American College of Allergy, Asthma & Immunology Annual Scientific Meeting.
“This shows that continued treatment for an additional 12 months, for a total of 24 months duration, provides additional enhancement of the treatment effect, with almost 84% of VP250 subjects reaching the primary study endpoint, and 55% being able to finish the cumulative amount of peanut protein provided in the oral food challenge of 3.34 g, which is almost the amount of peanut in two full-sized Reese’s peanut butter cups,” Matthew Greenhawt, MD, director of the food challenge and research unit at Children’s Hospital Colorado, told Healio. “This shows an enhanced efficacy effect without any additional severe allergic reactions.”
As Healio previously reported at last year’s ACAAI Annual Scientific Meeting, with a subsequent publication in The New England Journal of Medicine, Greenhawt and colleagues of the EPITOPE trial found that using the VP250 skin patch — which contains 250 µg peanut protein, or the equivalent of approximately 1/1,000 of a single peanut — daily for 12 months led to 67% of children aged 1 to younger than 4 years meeting the study’s responder criteria compared with only 33.5% assigned placebo.
In the long-term extension to this trial, EPOPEX, Greenhawt and colleagues are continuing to assess treatment safety and efficacy over longer durations of treatment in the original VP250 cohort, as well as in the cohort of patients originally assigned placebo who crossed over to treatment with VP250.
The current interim analysis included 166 children originally from the VP250 cohort and 78 from the placebo cohort who underwent 24-month double-blind placebo-controlled food challenges (DBPCFC).
The study’s endpoints included the proportion of children reaching eliciting doses of 1,000 mg or greater (3-4 peanuts) or 2,000 mg or greater (6-8 peanuts); the proportion of patients able to complete the DBPCFC without meeting stopping criteria; and the percent of treatment responders as defined in EPITOPE with two thresholds: 1,000 mg or greater if the baseline eliciting dose was greater than 10 mg, and 300 mg or greater if the baseline eliciting dose was 10 mg or less.
After 24 months of treatment, 81.3% of those assigned VP250 reached an eliciting dose of 1,000 mg, up from 74.7% at 12 months and from the 64.2% figure reported in the full EPITOPE treatment cohort, which included those who did not participate in EPOPEX. Also, 63.8% reached an eliciting dose of greater than 2,000 mg, up from 52.4% at 12 months and from the 37% figure reported from the full EPITOPE cohort.
Also, the proportion of treatment responders increased from 67% after EPITOPE — with a rate of 77.4% reported for those who went on to enroll in EPOPEX — to 83.9%, and 55.9% completed the DBPCFC without meeting stopping criteria, up from 30.7% (full EPITOPE cohort) and 39.5% (EPOPEX-only cohort).
Among the population who crossed over to VP250 treatment after 1 year on placebo, researchers reported that 62.7% reached an eliciting dose of at least 1,000 mg, 36.5% reached an eliciting dose of at least 2,000 mg, 68% met treatment responder criteria and 28.4% completed the DBPCFC without meeting stopping criteria.
The fact that these results are “nearly identical” to the data presented last year after 1 year of treatment in the original VP250 cohort “was to be expected and adds additional power to bolster the already strong findings seen with 12 months of VP250 treatment,” Greenhawt told Healio.
In terms of safety, researchers reported no cases of treatment-related anaphylaxis or treatment-related serious adverse events in the original VP250 cohort in their second year of treatment, with one such incidence in the cohort that crossed over from placebo. Researchers noted that local application site reactions occurred less frequently in the second year of treatment as well.
Next, researchers plan to continue this study for up to 3 years of treatment duration.
Also, researchers are planning to conduct the COMFORT trial, with enrollment of children aged 1 to 3 expected in the first quarter of next year.
“The FDA has provided feedback just last week on the final design elements for the COMFORT real-world safety study ... which will enhance the safety dataset required by the FDA before [biologic license application] submission,” Greenhawt said, adding that enrollment of children aged 4 to 7 years in the phase 3 VITESSE study of VP250 in slightly older children is ongoing as well.