The Butantan Institute has developed a lyophilised tetravalent live-attenuated dengue vaccine, Butantan-DV, analogous to the US National Institutes of Health (NIH) TV003 admixture. A two-step, double-blind, randomised placebo-controlled phase 2 trial was conducted to assess the safety and immunogenicity of Butantan-DV in healthy volunteers aged 18–59 years in São Paulo, Brazil. The trial involved 300 participants, including both dengue-naive and dengue-exposed individuals. Participants were randomly assigned to receive Butantan-DV, TV003, or placebo.
Butantan-DV and TV003 were found to be immunogenic and well-tolerated, with no serious adverse reactions observed. The most frequent adverse event was rash, occurring in 16 out of 19 participants in the Butantan-DV group and 13 out of 17 in the TV003 group. Seroconversion rates were high among participants, with 87% achieving seroconversion to DENV-1, 92% to DENV-2, 76% to DENV-3, and 89% to DENV-4 in the dengue-naive group. Similar rates were observed in the dengue-exposed group.
The study concluded that Butantan-DV and TV003 are safe and induce balanced neutralising antibody responses against the four dengue virus serotypes. The efficacy evaluation of the Butantan-DV vaccine is ongoing. This research represents a significant step forward in the development of a dengue vaccine that could provide protection against all four serotypes of the virus, addressing a major global public health challenge.
