The tetravalent dengue vaccine developed by the Butantan Institute maintained 80.5% efficacy against severe cases and warning signs after 5 years of follow-up, according to a study published in the journal last Wednesday (March 4, 2026).
The phase 3 clinical trial, which took place between 2016 and 2019, brought together 16,235 participants aged 2 to 59 years at 16 research centers in Brazil. Of this total, 10,259 received a single dose of the vaccine and 5,976 received a placebo. Those recruited by the study were monitored until 2024.
There were no hospitalizations in the vaccinated group, compared to 8 records in the placebo group.
In the prevention of symptomatic dengue – which is when any symptom of the disease appears – the overall effectiveness was 65% throughout the period analyzed.
The immunizer is tetravalent, that is, it was developed to protect against the 4 existing serotypes of the dengue virus. These are the genetic variations of the dengue virus. In Brazil, serotype 3 (DENV-3) is known to be the main cause of serious cases of the disease.
Vacina not SUS
The vaccine, called Butantan-DV, was approved by Anvisa on November 26, 2025 for people aged 12 to 59 years. With this, the Ministry of Health (MS) began the process of including the immunizer in the SUS (Unified Health System) in January this year.
The Butantan Institute has already sent 1.3 million doses to the National Immunization Program. The MS started vaccination in the municipalities of Nova Lima (MG), Maranguape (CE) and Botucatu (SP), in a pilot project. The expectation, according to , is that immunization will expand as new studies regarding the vaccine are published.
With information from .
