Project points to potential benefit of selenium against Chagas disease

Celebrated last Sunday (January 30), the World Neglected Tropical Diseases Day draws attention to infections that affect more than one billion people worldwide, and yet receive little in terms of attention and investment. These diseases, such as Chagas disease, dengue fever, leishmaniasis, hanseniasis, schistosomiasis and worm-related illnesses, affect mostly poor people, resulting in death or in great health problems, worsening people’s quality of life as they make it harder to remain in school and in the workforce.

Selenium was evaluated for the first time in patients with chronic Chagas heart disease

Among the different facets of negligence, including lack of access to available preventive, diagnostic and therapeutic measures, is the low investment in research and development for safe and effective therapies. It is in this context that Project Selenium, led by the Oswaldo Cruz Institute (IOC/Fiocruz) in a partnership with the Evandro Chagas National Infectiology Institute (INI/Fiocruz), celebrates another step taken in the search for a new therapy for the heart issues caused by chronic Chagas disease.

Published on EClinicalMedicine, the result of the first clinical trial with selenium supplementation for patients with Chagas cardiopathy showed a potential benefit provided by the treatment in at least one subgroup of patients. The trial studies patients with chronic Chagas disease and heart conditions ranging from mild to moderate, classified as stage B. The study confirmed selenium is safe and no side effects were reported. In the subgroup of patients with moderate cardiopathy, classified as stage B2, analysis showed that the heart conditions improved after the treatment.

According to the authors of the trial, the result is positive and shows that new studies should be carried out. “We generated the first batch of evidence, obtained in a randomized clinical trial, on the benefits of selenium in stage B2 patients with chronic cardiopathy due to Chagas disease. It is a statistically significant result, but the sample is small. Now, it is important to confirm these findings in new studies that include longer follow-up period, more patients in the B2 stage, patients in stage C, and volunteers from different parts of Brazil”, states the coordinator of the project, researcher of the Laboratory of Innovations in Therapies, Teaching and Bioproducts and director of IOC/Fiocruz, Tania Cremonini de Araujo-Jorge.

“This was the first randomized clinical trial that tested the use of selenium to prevent the worsening of the heart’s contraction function in Chagas cardiopathy. The trial showed that there is a subgroup of patients for whom the treatment was beneficial, which lifted our spirits and generated questions for new research”, adds the first author of the paper, cardiologist and researcher of the Laboratory of Clinical Research on Chagas disease of INI/Fiocruz, Marcelo Holanda.

Sixty-six patients treated at the day clinic of Chagas disease of INI/Fiocruz participated in the research. In order to evaluate the effect of the treatment, the volunteers were divided in two groups. One group was given daily supplementation with selenium capsules, while the other, the control group, was given identical capsules containing an inert compound (placebo). Each patient was followed for an entire year, with clinical visits, laboratory tests and heart exams.

Scientific effort

Project Selenium is the result of a long scientific effort in the search for a treatment for a disease that causes high mortality and yet remains neglected. According to the World Health Organization (WHO), between six and seven million people have chronic Chagas disease all over the world. In Brazil, the Ministry of Health states that there are between one and four million people affected by the condition, with many cases never having been diagnosed.

Heart problems occur in about 30% of subjects with chronic Chagas disease, affecting between 400 and 900 thousand people in Brazil alone. About 4.5 thousand brazilians die of Chagas disease every year, and most of these deaths are caused by heart conditions, such as arrhythmia, heart failure, thromboembolism and sudden death.

“Among all cardiopathies, chronic Chagas cardiopathy is the one with worse morbimortality rates. When we compare clinical outcomes, hospitalizations and deaths, Chagas cardiopathy is the one with the worst prognosis. This is why it is necessary to search for new treatment strategies”, emphasizes infectologist Alejandro Hasslocher.