Valneva Reports Positive Final Phase 2 Antibody Persistence and Safety Results in Children for its Chikungunya Vaccine IXCHIQ®

Core Insights - Valneva SE announced positive final antibody persistence and safety data for its Phase 2 clinical trial of the chikungunya vaccine IXCHIQ, showing promising results in 304 children twelve months post-vaccination [1][2][3] Vaccine Efficacy and Safety - The full dose of IXCHIQ elicited a 94.7% seroresponse rate in chikungunya virus-naïve children at Day 360, indicating a strong immune response [3][4] - The vaccine was well tolerated across all age groups tested, with no safety concerns identified [3][4][9] - The trial results align with previous data reported in January and June 2025, confirming the robustness of the immune response and safety profile [2][5] Future Development Plans - The company plans to initiate a Phase 3 study in children after gathering additional real-world experience in the adolescent population, emphasizing the importance of safety [5][9] - The selection of the full dose for future trials is supported by the favorable immune response and safety data observed [4][9] Chikungunya Context - Chikungunya has seen a significant rise in cases globally, with Brazil reporting over one million cases from January 2019 to July 2024, highlighting the urgent need for effective vaccination [5][7] - The World Health Organization has identified chikungunya as a major public health problem, with the disease affecting over 110 countries since its re-emergence [6][7] Trial Details - The Phase 2 trial (VLA1553-221) was a multi-center, randomized, observer-blinded study involving 304 healthy children aged one to eleven years, conducted in the Dominican Republic and Honduras [8][10] - Participants were randomized to receive either a full dose, a half dose, or an active control, with the primary focus on evaluating safety and immunogenicity [8][10]