Immuron Publishes Phase 2 Trial Results for Travelan®

MELBOURNE, Australia, Oct. 13, 2026 /CourierPR/ -- Immuron Limited, an Australian biopharmaceutical company, has announced the publication of its Phase 2 clinical trial results for Travelan®, an orally administered passive immunotherapy. The study, published in the Nature Journal, Scientific Reports, evaluated the efficacy and safety of once-daily oral Travelan® in preventing travelers' diarrhea caused by enterotoxigenic Escherichia coli (ETEC).

The clinical trial, partially funded by the U.S. Department of Defense (MTEC Award 21010.13), demonstrated that Travelan® was safe and well-tolerated. The study showed a statistically significant 50% reduction in ETEC challenge-related adverse events compared to the placebo group (P=0.0001). However, the lower-than-anticipated placebo attack rate (33% versus 70%) reduced the statistical power of the study, which did not meet its primary efficacy endpoints.

Despite this limitation, the efficacy results consistently trended in favor of Travelan® across multiple clinically meaningful endpoints. Specifically, the study reported a 40% reduction in moderate-to-severe diarrhea, a 50% reduction in severe diarrhea, and a 44% reduction in all diarrhea. Additionally, Travelan® recipients showed a 71% reduction in early antibiotic use, with lower fecal myeloperoxidase (p=0.04) and calprotectin (p=0.06) levels than the placebo group. More than 80% of subjects in both arms seroconverted (IgG/IgA anti-ETEC) by day 15-29, indicating that Travelan® did not impair natural adaptive immunity to the challenge strain.

Immuron is advancing Travelan® as a next-generation, non-antibiotic oral immunoprophylactic for the prevention of bacterial diarrheal disease. The program aims to deliver a military-ready, once-daily formulation capable of providing broad-spectrum protection against key pathogens responsible for travelers' diarrhea and military deployment-related gastrointestinal infections. Building on the encouraging findings from the US Government-supported clinical study, including a reduction in diarrhea severity and consistently favorable efficacy trends, Immuron has developed a next-generation, delayed-release capsule formulation optimized for once-daily dosing. This novel formulation enables the delivery of a substantially higher payload and may be investigated in larger, adequately powered clinical studies to further assess its potential to protect against ETEC-associated disease and broader bacterial gastrointestinal infections.

In Australia, Travelan® is a listed medicine on the Australian Register for Therapeutic Goods (AUST L 106709) and is indicated to reduce the risk of travelers' diarrhea, reduce the risk of minor gastrointestinal disorders, and is antimicrobial. In Canada, Travelan® is a licensed natural health product (NPN 80046016) and is indicated to reduce the risk of travelers' diarrhea. In the U.S., Travelan® is sold as a dietary supplement for digestive tract protection.

Travelers' diarrhea (TD) is generally defined as the passage of three or more unformed stools per 24 hours plus at least one additional symptom, such as nausea, vomiting, abdominal cramps, fever, blood/mucus in the stools, or fecal urgency, that develop while abroad or within 10 days of returning from any resource-limited destinations (Leung et al., 2006). Diarrhea continues to be the most frequent health problem among travelers to destinations in lower- and middle-income regions. Deployed US military personnel, essentially representing a long-term traveler population, are particularly affected given their population dynamics and the context in which they seek care and treatment. Diarrhea is the leading infectious disease threat to the overall health and preparedness of deployed US armed forces, with diarrheagenic E. coli, Campylobacter spp., and Shigella spp. among the most commonly reported etiologies.

Immuron's proprietary technology is based on polyclonal immunoglobulins derived from engineered hyper-immune bovine colostrum. The company has the capability of producing highly specific immunoglobulins to any enteric pathogen and its products are orally active. Bovine IgG can withstand the acidic environment of the stomach and is resistant to proteolysis by digestive enzymes found in the gastrointestinal (GI) tract. Bovine IgG also possesses the unique ability to remain active in the human GI tract, delivering its full benefits directly to the bacteria found there. The underlying nature of Immuron's platform technology enables the development of medicines across a large range of infectious diseases. The platform can be used to block viruses or bacteria at mucosal surfaces such as the GI tract and neutralize the toxins they produce.

The development of IMM-124E (Travelan®) was achieved using Immuron's platform technology. IMM-124E is produced from the colostrum of birthing cattle that have been immunized during pregnancy with a vaccine containing the outer antigens of multiple human-derived ETEC strains. A total of 13 ETEC strains are used in the vaccine to produce high levels of antibodies against selected surface antigens from the most common strains of ETEC.