This pilot campaign will serve as the foundation for post-marketing studies to be conducted following the vaccine's approval, aiming to assess its effectiveness and safety under real-world conditions, and to generate data on a large population.

The campaign will be rolled out in ten strategically selected Brazilian municipalities. Adults aged 18 to 59 will be invited to participate, with a target of achieving 20 to 40% vaccination coverage within the target population.

Valneva, through Instituto Butantan, will donate up to 500,000 doses of Ixchiq to the Brazilian Ministry of Health for this program. The vaccine received market authorization in Brazil in April 2025, for individuals aged 18 and older.

The company notes that, to date, Brazil has reported the highest number of chikungunya cases worldwide, with more than one million cases between January 2019 and July 2024, including 263,502 cases in 2024 alone, resulting in 246 deaths.