Safety, Virological and Immunological Assessment of the Controlled Dengue Human Infection Model in Dengue-Immune Participants in Thailand (DHIT-Immune)

rDEN2Δ30-7169 is a dengue challenge strain that previously reports its viremia induction effect in participants with minimal symptoms in US flavivirus naïve participants. Moreover, preliminary result of five Thai dengue naïve participants from previous project (registered number NCT05476757) demonstrated 100% viremia status without severe adverse event after 60 days post-virus challenge. However, result from previous project may not fully represent the clinical manifestation and immunological responses of major population of endemic areas, where most people in endemic area have dengue immune status. Therefore, this controlled human infection model protocol proposes to challenge the attenuated virus in 12 dengue-immune participants recruited from Bangkok metropolitan area, Thailand. We aim to assess the safety, viremia, NS1 antigenemia profile, and immunogenicity of the challenge virus in the dengue immune participants. After finish safety assessment, all participants will be vaccinated with a full course of dengue vaccines to prevent recurrent dengue infection. Immunological responses after vaccination will be also evaluated the vaccine efficacy. Our expected outcomes are all participants present viremia profiles after virus challenge without serious adverse events (SAE). The exploratory profiles include assesment of immune profiles and parameters comparison with the other dengue challenge study.

NCT Number	NCT06908018
Lead Sponsor	Mahidol University Collaborators: National Institutes of Health (NIH), Johns Hopkins University
Conditions	Safety Issues, Dengue, Viremia, Immune-related Adverse Event
Enrollment	12 participants
Start Date	2025-09
Primary Completion	2026-06 (estimated)
Study Completion	2028-09 (estimated)
Updated on ClinicalTrials.gov	2025-04-03