Mustafa Özçam, PhD: Investigating Gut Microbiome in Children with Peanut Allergy

Data from an investigation that sought to identify the functional and metabolic features of the gut microbiome that related to primary clinical endpoints achieved in the Peanut Oral Immunotherapy in Children (IMPACT) trial was presented at the American Academy of Allergy, Asthma & Immunology (AAAAI) 2023 Annual Meeting in San Antonio, TX.

The randomized, double-blinded, placebo-controlled study achieved the primary endpoints of desensitization (D+) in 71% or desensitization and remission (D+R+) in 21% of children treated with peanut oral immunotherapy (POIT). These results indicated that variance in pre-treatment fecal microbiota composition, microbial gene content, and metabolism related to desensitization and remission outcomes.

In an interview with HCPLive, Mustafa Özçam PhD, postdoctoral fellow, Lynch Lab, Division of Gastroenterology, Department of Medicine, University of California San Francisco, explained that previous findings have shown that gut microbiome composition of children with food allergies vary from that of healthy children.

"Our data over the years suggest that the gut microbiome composition and metabolic perturbation in early life is associated with allergy and asthma development later in childhood," he said. "So, seeing data from the IMPACT clinical trial, different children responded differently to all immunotherapy made us wonder whether or not it's related to gut microbiome composition."

The team of investigators found that children responded differently to peanut oral immunotherapy with treatment in early age and had a lower level of IgE at baseline were more likely to develop desensitization and remission to their allergy.

"It's a really great achievement for the group, that 70% of children who were treated with peanut oral immunotherapy, develop desensitization after the treatment, and 20% of those children kept their desensitization and were considered as in remission after the avoidance," Özçam said.

Samples were collected before, during and after avoidance, along with different times throughout the 160-week study period. They found that children who responded to the treatment exhibited a phylogenetically distinct fecal microbiota throughout the course of the trial.

"We first started with extracting DNA and performing microbiota analysis with 16S rRNA sequencing, which is a faster way of identifying if there is any relationship between gut microbiome composition and peanut oral immunotherapy outcomes," he explained. "We find interesting results, so we dive into details and we want to understand what is the molecular mechanism by which microgram would induce desensitization or would be associated with desensitization."