Sirivichayakul C.Barranco-Santana E.A.Rivera I.E.Kilbury J.Raanan M.Borkowski A.Papadimitriou A.Wallace D.Mahidol University2023-06-182023-06-182022-05-01Journal of Infectious Diseases Vol.225 No.9 (2022) , 1513-152000221899https://repository.li.mahidol.ac.th/handle/20.500.14594/85950Background: We report long-term safety and immunogenicity of Takeda's tetravalent dengue vaccine candidate (TAK-003) in healthy children and adults living in dengue-endemic areas in Puerto Rico, Columbia, Singapore, and Thailand. Methods: In part 1 of this phase 2, randomized, placebo-controlled trial we sequentially enrolled 1.5-45 year olds (n = 148) into 4 age-descending groups, randomized 2:1 to receive 2 doses of TAK-003 or placebo 90 days apart. In part 2, 1-11 year olds (n = 212) were enrolled and randomized 3:1 to TAK-003 or placebo groups. We assessed neutralizing antibody titers for the 4 dengue serotypes (DENV) up to month 36 in part 1, and symptomatic dengue and serious adverse events (SAEs) up to month 36 in both parts. Results: At month 36, seropositivity rates were 97.3%, 98.7%, 88.0% and 56.0% for DENV-1, -2, -3 and -4, respectively. Seropositivity rates varied significantly for DENV-4 according to serostatus at baseline (89.5% in seropositives versus 21.6% in seronegatives). No vaccine-related SAEs were reported. Conclusions: The trial demonstrated persistence of neutralizing antibody titers against TAK-003 over 3 years in children and adults living in dengue-endemic countries, with limited contribution from natural infection. TAK-003 was well tolerated.MedicineArticleSCOPUS10.1093/infdis/jiaa4062-s2.0-850926367701537661332658250