Brazil Suspends Butantan-DV After 2 Deaths, Raising Questions Over India's 10,335-Volunteer DengiAll Trial
Updated
Updated · The Hindu · Jun 15
Brazil Suspends Butantan-DV After 2 Deaths, Raising Questions Over India's 10,335-Volunteer DengiAll Trial
3 articles · Updated · The Hindu · Jun 15
Summary
Brazil halted Butantan-DV on June 8 after 42 recipients developed serious side effects, including 2 deaths and 1 intensive-care case, during a campaign that had vaccinated about 500,000 people.
Researchers are scrutinizing whether antibody-dependent enhancement drove the severe dengue-like reactions, a risk that can emerge when cross-reactive antibodies from live attenuated tetravalent vaccines fall to inadequate levels.
India's DengiAll faces added scrutiny because it is built on the same NIH-derived TV003/TV005 platform as Butantan-DV and uses the same four live weakened dengue serotypes.
Phase 3 gaps deepen the concern: Butantan-DV's protection against DENV-3 and DENV-4 remains unclear because those serotypes were scarce during Brazilian trials, echoing past problems seen with Sanofi's Dengvaxia.
Panacea Biotec's DengiAll trial enrolled 10,335 volunteers in January and is still following them for 2 years, while experts urge serotype-specific antibody testing and long-term pharmacovigilance before and after any India rollout.
Could a hidden genetic marker explain why a life-saving dengue vaccine turned deadly for a few?
Is a vaccine's rare but fatal side effect a greater public health threat than the disease it prevents?
Brazil Halts Butantan-DV Dengue Vaccine Following 2 Fatalities and 42 Severe Cases: What It Means for India’s DengiAll and Global Vaccine Safety
Overview
On June 8, 2026, Brazil suspended the Butantan-DV dengue vaccine after two suspicious deaths and 42 unexpected adverse events were reported among vaccinated individuals, including healthcare workers. These cases showed warning signs not seen in clinical trials, prompting the Ministry of Health, ANVISA, and the Butantan Institute to launch a thorough investigation. Although a direct link between the vaccine and the fatalities has not been established, the suspension is a precautionary measure to ensure safety. The investigation focuses on understanding these rare incidents and maintaining public trust in vaccination programs.