Travelers Diarrhea Orally Administered Passive Immunotherapy Posts Positive Phase 2 Results

Immuron Limited today announced that it had submitted the Clinical Study Report to the U.S. Food and Drug Administration (FDA) for the recently completed Phase 2 study with Travelan® (IMM-124E) and will soon request an end-of-Phase 2 meeting, which is a pre-cursor to proceeding to Phase 3.

As of January 14, 2025, the company wrote, 'This study data implies that Travelan® appears to aid in the reduction and clearance over time of pathological ETEC bacteria, by shortening the recovery period after Enterotoxigenic Escherichia Coli (ETEC) challenge.'

In the phase 2 study, statistically significant lower levels of IgA and IgG were observed for the subjects who received Travelan® compared to those who received the placebo, which may also reflect levels of exposure to ETEC antigen.

Travelan antibodies target and bind to ETEC antigen in the gastrointestinal tract, block LPS epitopes and therefore reduce antigen exposure, resulting in lower overall IgA and IgG antibody titers.

Clinical data also demonstrated a statistically significant reduction in colony-forming units in the stools of subjects who received Travelan® (p =0.0121), measured 48 hours post-challenge. This indicates faster clearance of the challenge strain from the GI tract.

Travelan® is an orally administered passive immunotherapy that prophylactically reduces the likelihood of contracting travelers’ diarrhea (TD). This digestive tract disorder is commonly caused by pathogenic bacteria and the toxins they produce.

TD continues to be the most frequent health problem among travelers to destinations in lower—and middle-income regions. Between 8% and 50% of travelers develop diarrhea, and the incidence depends on the country visited. However, travelers can have multiple episodes of diarrhea during one trip.

TD is different from a norovirus infection caused by nonenveloped, single-stranded RNA viruses. Norovirus causes viral gastroenteritis, which is sometimes referred to as stomach flu.

According to the U.S. CDC, norovirus is a commonly reported cause of diarrhea among travelers in confined spaces, such as on cruise ships.

As of January 2025, there are no norovirus vaccines available.

In the U.S., Travelan® is sold as a dietary supplement for digestive tract protection.