A next-generation oral microbiome therapeutic, EBX-102-02, demonstrated a favorable safety profile and signals of efficacy in patients with irritable bowel syndrome with diarrhea (IBS-D), according to results from Part 2 of the TrIuMPH study.

Study Findings

In this study, 60 adults with IBS-D (IBS Symptom Severity Score [IBS-SSS] ≥175) were randomized 2:1 to receive EBX-102-02 or placebo. Participants received 2 oral doses (8 capsules each) administered one week apart, with follow-up visits at Baseline, Week 1, Week 3, and Week 7.

All participants completed follow-up. No drug-related serious adverse events were reported. Adverse events were primarily mild, self-limiting, and gastrointestinal in nature.

Patients treated with EBX-102-02 experienced greater and sustained improvements in IBS-SSS compared with placebo. By Week 7, the mean reduction in IBS-SSS was 61 (15) points in the treatment group versus 38 (17) points with placebo. Quality of life also improved, with IBS-QoL scores exceeding the minimally important difference in the EBX-102-02 group (+12.1) compared with placebo (+7.4).

Bowel habit measures showed modest changes. The median proportion of stools classified as Bristol Stool Form Scale (BSFS) types 6 or 7 decreased from 66% to 48% in the treatment group and from 56% to 43% in the placebo group by Week 7. Weekly stool frequency declined from 17 to 13 with EBX-102-02 and from 17 to 12 with placebo.

Metagenomic sequencing demonstrated a significant and sustained shift in fecal microbiota composition toward the EBX-102-02 product signature, persisting through Week 7.

Clinical Implications

These findings suggest that EBX-102-02 may offer a novel therapeutic approach targeting the gut microbiome in IBS-D. While improvements in symptom severity and quality of life were notable, the lack of superiority over placebo in stool consistency and frequency highlights ongoing challenges in treating bowel habit abnormalities in IBS-D.

The observed microbiome shifts provide evidence of biological activity, supporting the mechanistic rationale for microbiome-based therapies. For clinicians, this may represent an emerging class of interventions that address underlying dysbiosis rather than focusing solely on symptom control.

Importantly, the favorable safety profile and high completion rate reinforce the tolerability of this oral regimen. However, the modest sample size and short follow-up period limit definitive conclusions regarding long-term efficacy and durability of response.

EBX-102-02 demonstrated safety and clinically meaningful improvements in IBS symptom severity and quality of life in IBS-D patients. Larger, longer-term studies are needed to confirm efficacy and define its role in clinical practice.

Reference:

McIlroy JR, Craven LJ, Smyth MLD, et al. A randomised double-blind placebo-controlled phase ii trial assessing the safety and efficacy of ebx-102-02, an oral full-spectrum intestinal microbiota product in patients with irritable bowel syndrome with constipation and diarrhoea; the TRIUMPH trial. Presented at: Digestive Disease Week; May 2–5, 2026; Chicago, Illinois.