Phase II Trial Now Recruiting, Investigates Microbiome as Immunotherapy Enhancer

A promising new strategy to revolutionize the treatment of peanut allergy is at the heart of a new Phase 2 clinical trial (NCT05695261) at Boston Children’s Hospital. The study, titled “Evaluating the Safety and Efficacy of Oral Encapsulated Microbiota Transplantation Therapy in Peanut Allergic Patients,” investigates whether modulating the gut microbiome can improve outcomes for patients, particularly when combined with traditional oral immunotherapy (OIT).

This innovative research is a major collaborative effort led by Principal Investigator Dr Rima Rachid, MD, and supported by a $1.3 million, four-year commitment from the Food Allergy Science Initiative (FASI). The overarching goal is to test if the combined treatment—Microbiota Transplantation Therapy (MTT) plus OIT—can significantly improve the safety, efficacy, and durability of food allergy treatment, thereby bringing researchers closer to safer, longer-lasting therapies for children.

The trial, which enrolls adolescents and young adults aged 12 to 17, is founded on the hypothesis that altering the gut bacteria composition can address the underlying immune dysregulation seen in allergic patients. The experimental regimen involves a two-step process:

1. Gut Modulation: Participants first receive a seven-day course of oral antibiotics (or a placebo) designed to temporarily suppress the existing gut flora.
2. Microbiota Restoration: This is followed by a 27-day regimen of Oral Encapsulated Microbiota Transplantation Therapy (MTT) capsules, which introduce a diverse consortium of healthy donor microbes to the gastrointestinal tract.

The trial is structured with two distinct parts to evaluate the therapy’s impact on different patient populations:

Part A: Testing Efficacy in Allergic Patients

This section involves 24 subjects with a confirmed baseline peanut allergy. It is a quadruple-masked (double-blind), randomized trial where participants receive either the active antibiotic/MTT combination or a matching placebo for both parts of the intervention. The primary goal is to measure if the MTT intervention can desensitize allergic patients, allowing them to tolerate a higher dose of peanut protein.

Part B: Enhancing Existing OIT Therapy

This crucial open-label part of the study involves 13 subjects who are already on a maintenance regimen of peanut oral immunotherapy (OIT). All participants in this group receive the active antibiotic and MTT capsules. By targeting the gut microbiome in patients already undergoing OIT, researchers aim to determine if this combination therapy offers better, more durable, and safer outcomes compared to OIT alone.

The trial is currently recruiting in Boston, Massachusetts, and is scheduled to be completed by early 2027.

To learn more and to determine whether your child may be eligible, contact:

Melanie Benitez
617-355-6117
Melanie.Benitez@childrens.harvard.edu