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]

Core Insights - Valneva SE announced positive six-month antibody persistence and safety data for its Phase 2 clinical trial of the chikungunya vaccine IXCHIQ in children, supporting the initiation of a pivotal Phase 3 study in early 2026 [1][2][8] Company Overview - Valneva is a specialty vaccine company focused on developing, manufacturing, and commercializing vaccines for infectious diseases, with a strong track record in advancing multiple vaccines from early R&D to approvals [10][11] - The company currently markets three proprietary travel vaccines, including the world's first and only chikungunya vaccine, and has a pipeline that includes candidates for Lyme disease, Shigella, and Zika virus [12] Clinical Trial Results - The Phase 2 trial (VLA1553-221) involved 304 healthy children aged one to eleven years, demonstrating that a full dose of the vaccine elicited a more robust immune response compared to a half dose, with a 96.5% seroresponse rate at Day 180 [2][3][8] - The vaccine was well tolerated across all age groups tested, with no safety concerns identified, supporting the selection of the full dose for the upcoming Phase 3 trial [4][5][8] Market Context - Chikungunya poses a significant health risk, particularly in endemic areas, with Brazil reporting over one million cases from January 2019 to July 2024, and India reporting 370,000 cases during the same period [5][7] - The World Health Organization has identified chikungunya as a major public health problem, with the economic impact expected to grow due to climate change and the geographical spread of mosquito vectors [7]

Core Insights - Valneva SE has received marketing authorization from Brazil's ANVISA for its single-dose chikungunya vaccine IXCHIQ®, marking the first approval of a chikungunya vaccine in an endemic country [1][2] - The vaccine is part of Valneva's strategy to enhance access in low- and middle-income countries (LMICs), supported by CEPI and the EU [1][6] - The approval allows for large-scale clinical trials in Brazil, including Phase 4 trials to gather additional data on vaccine effectiveness [3] Company Developments - IXCHIQ® is already approved in the EU for individuals aged 12 and older and in the U.S., Canada, and the U.K. for those aged 18 and older [2] - Valneva is collaborating with Instituto Butantan for local manufacturing and distribution of the vaccine in Brazil, with potential approval for another vaccine candidate, VLA1555, expected in mid-2025 [4] - The company aims to ensure rapid access to its vaccines in Brazil and other regional markets, addressing a significant public health need as Brazil reported over 1 million chikungunya cases since 2019 [5][6] Clinical Trials and Research - Valneva is conducting a Phase 2 trial in children aged 1 to 11 years in the Dominican Republic and Honduras, with positive results reported in January 2025 [7] - A pivotal Phase 3 study in children is expected to begin in Q4 2025, with plans to evaluate the vaccine in pregnant women in outbreak-affected countries [8] Public Health Context - Chikungunya virus, transmitted by Aedes mosquitoes, has caused significant outbreaks globally, with over 720,000 cases reported in the Americas from January to July 2023 [5][10] - The World Health Organization has identified chikungunya as a major public health issue, with the disease's economic impact expected to grow due to climate change [10]