Benznidazole treatment during the early phases of chronic Chagas disease infection significantly reduced parasitemiaas well as the prevalence of markers of severe cardiomyopathy and mortality after 2 years of follow-up, according to data published in PLoS Neglected Tropical Diseases (ClinicalTrials.gov: NCT02646943).
Patients with Chagas disease from 21 remote towns were enrolled and a total of 1813 were evaluated at baseline and after the 2-year follow-up. The treatment group included 493 patients who had previously received at least 1 course of benznidazole, and the remaining 1320 participants formed the control group. Mortality after 2 years was 6.3%. The mortality rate was 2.8% in the treatment group and 7.6% in the control group (adjusted odds ratio [OR], 0.37; 95%CI, 0.21-0.63). Typical abnormal electrocardiograms associated with Chagas disease and high age-adjusted N-terminal pro brain natriuretic protein levels indicative of heart failure were also lower in the treatment group (OR, 0.35; 95%CI, 0.23-0.53), as were rates of polymerase chain reaction positivity (OR, 0.35; 95%CI, 0.27-0.45).
The duration of previous drug treatment was self-reported and most patients had used benznidazole up to 10 years prior to study participation. Therefore, the information concerning dosages and duration of treatment is less reliable as a result of memory bias. Further, the study investigators could not confirm the similarities in the clinical profiles of those who had received treatment. Investigators attempted to reduce these common observational study design biases as much as possible using a matching method, which was confirmed by multivariate analysis.
The study investigators concluded that “if used in the early phases of the disease, benznidazole treatment may result in better clinical and parasitological outcomes.” This remains an important finding because there are millions of cases of untreated Chagas disease globally and there is a lack of new treatment options. Investigators further suggested that “it is reasonable to consider treating all Chagas disease patients without advanced cardiopathy with benznidazole, especially those who are less than 50 years of age.”
Cardoso CS, Ribeiro ALP, Oliveira CDL, et al. Beneficial effects of benznidazole in Chagas disease: NIH SaMi-Trop cohort study. PLoS Negl Trop Dis. 2018;12:e0006814.