The gut microbiome is emerging as a potential target for the prevention of food allergies. Researchers at the 2026 AAAAI Annual Meeting presented data from studies addressing the role of the gut microbiome in children with food allergies.

Following these presentations, featured expert Brian P. Vickery, MD, was interviewed by Conference Reporter Associate Editor-in-Chief Mona Shah, PharmD. Clinical perspectives from Dr Vickery on these findings are presented here.

Approximately 70% of the immune system resides in the intestine, so it is clear that the gut microbiome influences the immune system. This is especially relevant to food allergies. I think there is now clear evidence that the gut microbial composition of individuals who go on to develop allergic disease is different from the gut microbial composition of individuals who do not develop allergic disease. However, this reflects an association, and we are still trying to understand causality in this area.

The questions then become: What are these different microbes that are absent in people with food allergies and present in people without food allergies, or vice versa, actually doing? Are there microbial compositions that are influencing the behavior of the immune system or are associated with disease? This gets us to the potential for intervention, and the obvious question becomes: How do we use this information to get the right composition of microbes and restore the gut immune system to health?

Interventional studies are currently an area of great interest in food allergies, but most probiotic studies that have been done in food allergies have failed. I think that this may be due to the fact that we do not yet fully understand the role of individual microbes in food allergies. Another consideration is the rapid nature of bacterial colonization. Newborns are immediately colonized with different bacteria, and, while the composition of the gut microbiome changes during the first few years of life, a more settled microbiome begins to be reached at grade-school age. It can therefore be difficult to know how to perturb that system when there are potentially trillions of bacteria. A daily Lactobacillus supplement may not do anything because it might be too late or it might not be the right bacteria to use. So, while there is a lot of interest and promise in research manipulating the gut microbiome, it is not yet ready to impact clinical practice.

The ADORED study, which I presented as a late-breaking abstract at the recent 2026 AAAAI Annual Meeting, is probably one of the best examples of where we can actually think about influencing the development of the gut microbiome to achieve the result we want (abstract L32). ADORED is a phase 1b/2, international, randomized, placebo-controlled trial that included 238 at-risk newborns who were randomized to a multistrain, live-bacteria, investigational therapeutic product vs placebo. This was a product composed of 3 bacteria that were selected intentionally based on preclinical work and mapping studies. These 3 strains are found in the gut of healthy individuals who do not develop food allergies and are absent in the gut of individuals who go on to develop food allergies. The study only included newborns, which is important because colonization occurs early. So, in this case, the strategy was to intervene before the gut microbiomes are established.

In the ADORED study, we found that those infants who received 1 year of this treatment had an approximately two-thirds lower odds of developing physician-diagnosed atopic dermatitis. An analysis of all patients, including those who withdrew from the study, showed a trend but not statistical significance. Statistical significance was achieved when we looked at those who had actually taken the whole year of treatment. We also saw a significant reduction in the rate of physician-diagnosed food allergies in the completer analysis at 1 year. In addition, overall, the treatment had a low incidence of adverse events, including “adverse events of special interest” such as diarrhea and acute gastroenteritis. So, this study provides some early data on one of the first microbial-based interventions that could impact allergic disease onset. I think that there will be a phase 3 study, and we will see what happens. Will it replicate? Will the therapeutic product end up becoming a potential treatment option?

There were related mapping studies presented at AAAAI 2026, including the study by Erin Steinbach, MD, PhD, and colleagues (abstract D58), and others looking at specific strains of probiotics, including the studies by Eun-ae Yang, MD, et al (abstracts L13 and D33). However, these were in animal models and not humans. There may well be other therapeutic candidates in the pipeline, but I would highlight the ADORED study because it provided human data in an interventional, large, randomized controlled trial.