Anvisa, Brazil's health regulatory agency, has authorized the first human trials of Vivaxin, a vaccine developed entirely in Brazil against malaria caused by the Plasmodium vivax parasite, the most common form of the disease in the country. The authorization was published in the official gazette, according to CNN Brasil. The vaccine is the result of 15 years of research at CTVacinas, a center at the Federal University of Minas Gerais (UFMG), in partnership with the University of São Paulo and the pharmaceutical laboratory Cristália, as reported by Jornal Nacional.
The phase 1 study will enroll 48 healthy volunteers, aged 18 to 59, who have never had malaria. They will be monitored for about a year at the Clinical Research Center of UFMG's Hospital das Clínicas in Belo Horizonte. One group will receive three doses of the vaccine, 28 days apart; a control group will receive a placebo. At this stage, researchers are assessing safety, reactions to the injection, and the ability to trigger an immune response. Protection against the disease itself is not being tested yet.
What is confirmed and what is still preliminary
The laboratory results were described as encouraging by CTVacinas coordinator Ricardo Gazzinelli, but he himself cautions that preclinical work does not guarantee performance in humans:
"It has a distinguishing feature: it encodes pieces of the parasite's different variants. It is not a vaccine against a single variant. What we did in the lab worked 100%. Now that has to be tested in humans," Gazzinelli told Jornal Nacional.
If phase 1 confirms safety and immune response, the next two phases, with more than 300 volunteers, will take place in the Amazon, where the disease is endemic. Only after those steps do the scientists plan to apply for full registration with Anvisa. The researchers expect the vaccine to reach public health posts in five to seven years, a timeline that depends on the success of each phase.
The potential impact is large. Brazil recorded 118,000 malaria cases in 2026, almost all in the Amazon region, which accounts for more than 99% of the country's locally transmitted cases, according to CNN Brasil. Worldwide, the World Health Organization estimated 282 million cases and 610,000 deaths in 2024. The two malaria vaccines currently recommended by the WHO protect against Plasmodium falciparum, which predominates in Africa. The vivax form affected 9.9 million people last year, according to Anvisa's director-president, Leandro Safatle, who described Vivaxin as the first vaccine in the world developed against this type of malaria, with the potential to help eliminate the disease in the Americas.
Until a vaccine arrives, prevention remains unchanged. Malaria causes fever, chills, headache, fatigue, nausea, and loss of appetite; severe cases can lead to anemia, altered consciousness, and damage to organs such as the liver and spleen. Anyone who is in the Amazon region, or has recently returned from it, and develops a fever should seek care and mention the trip, because early diagnosis and full treatment, available free through Brazil's public health system, the SUS, prevent severe disease. Bed nets, repellent, and long-sleeved clothing remain the recommended protective measures in endemic areas.