Immuron Limited has won an A$3.5m ($2.3m) grant to develop a version of its anti-diarrhoeal medication Travelan, following support from the US Department of Defense (DoD).

The financing will fund a new agreement with the Naval Medical Research Command and Walter Reed Army Institute of Research, the latter being the largest biomedical research facility overseen by the DoD.

The aim of the collaboration is to develop an enhanced formulation of Travelan for military use against pathogens that cause diarrhoea, according to a 16 August press release. The new version will target bacterial pathogens Campylobacter, Shigella and Enterotoxigenic E coli strains (ETEC) that are not present in the current product formulation.

Travelan is an over-the-counter bovine colostrum product. Bovine colostrum is cow’s milk secreted during the first few days after calving and contains a range of immunoglobulins, growth factors, and cytokines that help with immune protection.

Travelan is a highly purified tablet preparation that prevents bacteria colonisation in the digestive tract associated with travellers’ diarrhoea.

The US DoD has already been working with Australia-based Immuron as it eyes wider effectiveness against diarrhoeal pathogens. The Naval Medical Research Command has ongoing ETEC and Campylobacter research programmes with the company while the Walter Reed Army Institute of Research is investigating the medication’s protection against Shigella.

In the past, the DoD has provided $3.43m to perform a randomised double-blind placebo-controlled Phase II trial (NCT05933525) for ETEC infection testing a once-daily dosing schedule for the treatment.

Immuron reported positive interim topline results from the study in March 2024, which showed that ETEC-induced moderate to severe diarrhoea was reduced by 36.4% following Travelan treatment compared to placebo. The protective efficacy of once-daily dosing was around 50% as effective as the currently recommended three times daily dosing regimen; Immuron stated this was a strong result given the lower-than-expected attack rate in the study. Based on the results, the company is proceeding to Phase III registration strategy with the US Food and Drug Administration (FDA).

Immuron said the new award aims to “identify and define pathways to formulate, characterise and perform preclinical testing of a military-relevant combined colostrum product”.

Infectious diarrhoea is the most common illness that US troops deployed overseas experience, according to a 2019 DoD Infectious Disease Threats Prioritisation Panel.