Walnut Oral Immunotherapy for Tree Nut Allergy

Blinded study product dosing begins with a 1-day oral desensitization protocol to walnut for subjects in the active arm. Starting at 0.1 mg protein and increasing to a maximum of 6 mg or until allergic symptoms develop. Subjects continue daily dosing of blinded OIT (walnut) with build-up every 2 weeks to a maximum daily dose of 1500mg at week 34, followed by 4 weeks of daily maintenance dosing. OFC to walnut and second tree nut occurs at week 38 then treatment is unblinded and open-label maintenance dosing occurs.

Blinded study product dosing begins with a one-day oral desensitization protocol with placebo (oat) powder. Subjects in the placebo group will undergo the same protocol as those in the active group with placebo OIT dosing. Unblinding to treatment assignment will occur after the 38 week oral food challenge. Placebo subjects will cross-over to active, open-label treatment with walnut powder after the 38 week oral food challenge. beginning with initial escalation day, through build-up and maintenance dosing per the same protocol sequence as noted for active, walnut powder. Subjects will complete an oral food challenge to walnut and the second tree nut at week 38 then will continue on long-term, open-label maintenance dosing until the end of study using same protocol design.

Open-label treatment phase begins after the 38 week oral food challenge with unblinding of treatment assignment. For those on active treatment, daily maintenance dosing occurs for up to a total of 298 weeks. For those on placebo treatment, cross-over to active, open-label treatment occurs using the same active treatment protocol. Placebo-crossover subjects will complete an oral food challenge to walnut and the second tree nut at week 38 of active therapy then continue on long-term, open-label maintenance dosing until the end of study using same protocol design. All subjects may reach a qualifying IgE to walnut/second tree nut early and will undergo an OFCs on and 4 weeks off OIT. All subjects will have OFCs on and 4 weeks off OIT at week 142 and at week 298, unless both walnut/second tree nut OFCs are passed at previous OFC prompting addition of these foods into the diet.