How Does Long-Term Walnut Oral Immunotherapy Affect Children with Tree Nut Allergies?

Amy Scurlock, MD, Arkansas Children's Hospital, and team conducted a study looking at walnut oral immunotherapy in a younger group (median age of 9) with tree nut allergies.

Scurlock explained at AAAAI 2017 in Atlanta, Georgia, that the team used a standard walnut oral immunotherapy protocol that had an initial day escalation followed by a build up phase to a maintenance dose of 1500mg. They had an initial placebo controlled portion in the first 38 weeks and completed a long-term follow up through 142 weeks.

The individuals involved in the study had to have had an allergy to both a walnut and another tree nut (pistachio, pecan, hazelnut, etc), so they could see if walnut oral immunotherapy could desensitize to the walnut and the tree nut.

Their cohort was small; of the 9 subjects they challenged, the team saw that 7 exhibited desensitization to both walnut and their second test tree nut. "Obviously it's a small pilot and they are preliminary findings, but I tink it's certainly something to build on," Scurlock said.

Scurlock acknowledged that down the line, the team would explore other novel approaches like using adjuvants, other immunemodulatory agents, or combination therapies. Many questions are still left unanswered, but Scurlock believed that a multi-center study with a bigger population could help answer questions surrounding optimal dose, duration, and safety.

Regarding the million dollar question of what causes tree nut allergies, Scurlock believed the root cause could be genetic disposition coupled with some kind of environmental trigger, though further research is certainly required.