Retrospective Analysis of the Second Year of Safety Surveillance of the Qdenga® (TAK-003) Vaccine in Private Vaccination Centers, Including a Sub-analysis of Safety in Adults Over 60 Years of Age

The TAK-003 vaccine, Qdenga, developed by Takeda, was approved by ANMAT in April 2023 and has been available in Argentina since November 2023 for individuals aged 4 years and older, with no upper age limit. Clinical trials demonstrate that Qdenga has a favorable safety and immunogenicity profile in individuals with and without prior dengue infection. However, real-world safety evidence remains limited, particularly in adults over 60 years of age. The aim of this study is to evaluate adverse events following immunization (AEFI) associated with TAK-003 during the second year of implementation and across the combined two-year period at private vaccination centers in the Buenos Aires metropolitan area, with a particular focus on older adults and hypersensitivity reactions.

Inclusion Criteria: * All individuals vaccinated with Qdenga at Vacunar centers between November 2, 2024 and November 1, 2025, aged 4 years and older with no upper age limit, in accordance with ANMAT approval (7), and for whom safety data are available through the passive surveillance systems of Vacunar centers. Exclusion Criteria: * Reports with insufficient information to characterize the AEFI will be excluded from the analysis.