BERGEN, Norway, July 7 (World Daily Times) — An experimental oral vaccine against a diarrhea-causing strain of E. coli may one day help protect young children in places where the infection is common, according to a phase 2b trial in The Gambia.
The vaccine, called ETVAX, was tested in about 5,000 children ages 6 to 18 months in a randomized, placebo-controlled study published in The Lancet Infectious Diseases. Researchers reported no vaccine-related serious adverse events.
The trial also found that ETVAX triggered immune responses against enterotoxigenic Escherichia coli, or ETEC, which is a major cause of childhood diarrhea in low-income settings.
Protection varied by analysis. The study reported 26.6% efficacy against the primary endpoint. When moderate-to-severe ETEC diarrhea was counted with co-pathogens, efficacy was 48.2%; it rose to 80.6% when children with certain intestinal parasites were excluded. Protection was 67.8% when vaccination began before 9 months of age and 21% against moderate-to-severe diarrhea from any cause.
The authors said the results provide the first demonstration of protective efficacy by ETVAX in young children at risk and support a larger, multicountry phase 3 trial. A 2025 review in PMC said no licensed ETEC vaccine is available yet.
