BERGEN, Norway, July 7 (World Daily Times) — A vaccine designed to block enterotoxigenic Escherichia coli, or ETEC, has shown early signs of protection in young children, raising the possibility of a future tool against one of the main causes of severe diarrhea in low-resource settings.
Researchers reported in The Lancet Infectious Diseases that the oral vaccine, ETVAX, was tested in a randomized, placebo-controlled phase 2b trial in The Gambia involving about 5,000 children ages 6 to 18 months. The study found no vaccine-related serious adverse events.
The trial also found that the vaccine triggered immune responses, including antibodies against ETEC colonization factors and heat-labile toxin, the researchers said. A separate review article on ETEC vaccine development said no licensed vaccine is available yet.
Protection varied by analysis. The authors reported 26.6% efficacy against the trial’s primary endpoint, 48.2% against moderate-to-severe ETEC diarrhea when co-pathogens were included, 80.6% when children with certain intestinal parasites were excluded, and 67.8% when vaccination began before 9 months of age. They also reported 21% protection against moderate-to-severe diarrhea from any cause.
The study authors called the results the first demonstration of protective efficacy by ETVAX in young children at risk and said the findings support a larger multicountry phase 3 trial in infants from low- and middle-income countries.
