The Efficacy of Butantan–Dengue Vaccine in Preventing Dengue Fever
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Reviewed & translated by Dat Tien Nguyen, B.A, ScM.
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Posted on March 18th, 2024
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To prevent dengue, there are currently 2 approved live-attenuated vaccines: Dengvaxia and Qdenga. The usage of Dengvaxia is limited to endemic regions to prevent severe infection in individuals with inadequate immunity. While Qgenda has high effectiveness, it is required to be administered in a series of 2 doses. Thus, a study was conducted to assess the efficacy of Butantan–Dengue, a single dose vaccine, to prevent dengue fever.
The phase 3 clinical trial was conducted in Brazil, and it included 16,235 participants between the age of 2 and 59 years old. Approximately half of the participants had been vaccinated with a dengue vaccine, and 96% of them had previously been exposed to the Dengue Virus (DENV) of various serotypes. The participants were randomly assigned to be administered with either placebo or the Butantan–Dengue vaccine, which contains chimeric live viral particles of the 4 serotypes that had been attenuated. After a follow-up period of 5 years, the researchers concluded that the Butantan-Dengue vaccine has an overall efficacy of 80%: 73.6% in those who had not been exposed to DENV, and 89.2% in those who had previously been exposed to the virus. Stratified analysis showed that the Butantan-Dengue vaccine has an efficacy rate of 89.5% against the DENV-1 serotype and 69.6% against the DENV-2 serotype. However, the researchers could not assess the efficacy against DENV-3 and DENV-4 due to their low prevalence in the community during the follow-up period.
The phase 3 clinical trial was conducted in Brazil, and it included 16,235 participants between the age of 2 and 59 years old. Approximately half of the participants had been vaccinated with a dengue vaccine, and 96% of them had previously been exposed to the Dengue Virus (DENV) of various serotypes. The participants were randomly assigned to be administered with either placebo or the Butantan–Dengue vaccine, which contains chimeric live viral particles of the 4 serotypes that had been attenuated. After a follow-up period of 5 years, the researchers concluded that the Butantan-Dengue vaccine has an overall efficacy of 80%: 73.6% in those who had not been exposed to DENV, and 89.2% in those who had previously been exposed to the virus. Stratified analysis showed that the Butantan-Dengue vaccine has an efficacy rate of 89.5% against the DENV-1 serotype and 69.6% against the DENV-2 serotype. However, the researchers could not assess the efficacy against DENV-3 and DENV-4 due to their low prevalence in the community during the follow-up period.