Dengue Efficacy & Safety Trial in African Region

The DENSTAR project aims to make a live attenuated tetravalent Dengue vaccine available in Africa and generate data supporting its broader use. DENSTAR aligns with the call's objective accelerating the development of a safe and effective Dengue vaccine against Dengue in Sub-Saharan Africa (sSA). Panacea Biotec, an Indian vaccine manufacturer, is developing a live attenuated tetravalent Dengue vaccine "DengiAll", based on the US NIH-NIAID technology (TV003). Preclinical toxicology and Phase I/II studies were completed, and DengiAll is currently undergoing phase III study in adults in India with results expected in 2026. NIH and other research groups have performed multiple clinical studies on NIH Dengue vaccine, indicating that the vaccine is safe and efficacious with demonstrated efficacy against Dengue serotype 1, 2 and 3. No serious safety concern, such as severe dengue due to antibody dependent enhancement (ADE), was reported for TV003 in a field efficacy study in Brazil. We intend to conduct a multi-center population-bridging trial in sSA including Ghana, Mozambique and Republic Democratic of Congo, to evaluate DengiAll safety and immunogenicity, and compare results with phase III study data from India. We plan to evaluate the efficacy of DengiAll against Dengue virus serotype 4 (DEN4) using controlled human infection model (CHIM). Although efficacy data for the NIH Dengue vaccine against other serotypes is available, there is no evidence for any live attenuated vaccine against DEN4 in humans. This gap has implications for safety and acceptability. To address this, we will establish a DEN4 human challenge model and conduct a DEN4 CHIM study in Gabon to evaluate DengiAll's efficacy. Upon successful completion of the population-bridging study and the efficacy trial in India, the data will be used to seek marketing authorization in sSA. A safe, effective, and affordable vaccine will be crucial in addressing the rising Dengue burden in sSA.