GlobeNewswire·Nov 9, 2026, 1:00 AM ET

Valneva Announces Positive Phase 2 Results for Tetravalent Shigella Vaccine Candidate S4V2

Valneva announced positive results from two Phase 2 trials of its Shigella 4V2 (S4V2) vaccine candidate, demonstrating a favorable safety profile & encouraging immunogenicity & efficacy signals.
The S4V02 infant trial in Kenya evaluated 110 infants aged nine months & found S4V2 had a favorable safety profile with mild to moderate adverse events that resolved without complications.
The S4V02 trial showed statistically significant increases in anti-LPS IgG antibody levels for all four targeted Shigella serotypes, with titers peaking after the second dose & remaining above baseline six months later.
The S4V03 controlled human infection model (CHIM) trial in the US involved approximately 120 healthy adults & met its primary endpoint with a statistically significant reduction in S. sonnei shigellosis incidence among vaccinated participants compared to placebo.
Shigellosis is the second leading cause of fatal diarrheal disease worldwide, causing an estimated 165 million infections annually, including 62.3 million cases in children under five.
The U.S. FDA granted Fast Track designation to S4V2 in 2024 to address this serious condition & unmet medical need.
LimmaTech sponsored both trials, with the infant trial supported by funding from the Gates Foundation.
Valneva is evaluating the complete datasets from both trials to determine the optimal path forward, including dose selection & vaccination scheduling, for future clinical development.