Long-term peanut SLIT safe, effective among children

ATLANTA — Peanut sublingual immunotherapy induced clinically significant desensitization in 86% of peanut-allergic children, as well as sustained unresponsiveness among children treated for 36-60 months, according to early data presented at the annual meeting of the American Academy of Allergy, Asthma & Immunology.

“In a 2011 study, we found that, in comparison to placebo, patients receiving 2 mg peanut sublingual immunotherapy underneath the tongue seemed to have a higher reaction threshold,” Edwin Kim, MD, from the University of North Carolina at Chapel Hill, said during a press conference. “The questions we wanted to answer was whether, with long-term therapy, would the benefit that the patients achieved with the change in threshold be higher, and if there is any potential for the lasting benefit of sustained unresponsiveness.”

Edwin Kim

Kim and colleagues enrolled children with peanut allergy aged 1-11 years to receive 2 mg of peanut sublingual immunotherapy (SLIT) for 36-60 months.

Following this treatment, patients underwent a 5,000 mg peanut oral food challenge to evaluate desensitization; children who passed the oral challenge were instructed to discontinue SLIT for 2-4 weeks and then re-challenged with 5,000 mg of peanut protein to measure sustained unresponsiveness.

According to study findings, among the 37 children who completed the study, 86% safely ingested >300 mg of peanut while 32% passed the 5,000 mg oral food challenge after SLIT.

“There is a great deal of discussion regarding what is clinically-significant protection,” Kim said. “We estimated 300 mg to be about the equivalent of one peanut, and since 86% of our patients had a reaction threshold that was higher than that, we would consider this clinically significant.”

In addition, the researchers found that the median amount of peanut successfully consumed was 1,750 mg, and the mean amount was 2,561 mg. The 12 patients who had passed the oral food challenge were re-challenged with 5,000 mg of peanut 2-4 weeks after discontinuing SLIT, of which 27% demonstrated sustained unresponsiveness.

“There continues to be a wide range of response to treatment,” Kim said. “We had some patients that did not respond well while a sizeable portion were able to eat the entire 5,000 mg challenge or close to that, so this is an area that we want explore further.” – by Bob Stott

Reference:
Kim E, et al. Abstract 559. Presented at: American Academy of Allergy, Asthma & Immunology Annual Meeting; March 3-6, 2017; Atlanta.

Disclosure: The researchers report no relevant financial disclosures.