Fixed vs adjusted-dose benznidazole for adults with chronic Chagas disease without cardiomyopathy: A systematic review and meta-analysis

Pharmacokinetics of two pharmaceutical presentations of benznidazole in adult Trypanosoma cruzi infected population

BACKGROUND

Benznidazole (BNZ) is the primary treatment for Chagas disease. While pharmacokinetic studies of BNZ began in the 1970s, its metabolism and excretion are not fully understood. Alternatives like Benznidazol Lafepe® and Abarax® have replaced the original Radanil®.

OBJECTIVES

To compare the pharmacokinetic profiles of both currently available formulations of BNZ in adults with chronic Trypanosoma cruzi infection.

METHODS

The study involved 13 subjects each one receiving 100 mg of both presentations one week apart. Blood samples were collected over 48 hours post-administration to analyse BNZ concentration and calculate pharmacokinetic parameters.

FINDINGS

The analysis showed that both presentations had similar maximum plasma concentration and time to reach maximum plasma concentration values. Area under curve (AUC) values were slightly lower in Abarax® than Benznidazol Lafepe®. High intra-individual variability was observed, attributed to erratic absorption patterns with multiple peaks in concentration-time curves. The half-life values for both formulations were 9.1 and 8.0 h, respectively, with a significant intra-individual variability over 30%.

MAIN CONCLUSIONS

The mean difference in the AUC was lower than 10%, but exceeded the 90% confidence interval for the higher bioequivalence limit. Despite the high variability that confirms erratic absorption, the pharmacokinetic parameters of both formulations were within expected ranges.

Trends in prevalence of major etiologies leading to heart failure in young patients: An integrative review

The prevalence of Heart failure (HF) is increasing with the aging of the population but it is estimated that 10% of HF patients are younger than 50 years-old. HF development in this population is characterized with a fast-growing prevalence, and important disparities according to underlying etiologies or gender. These observations highlight the need to identify specific and preventable factors in these patients, a topic that is under-studied. Here we provide an overview of trends in prevalence of major etiologies leading to HF in young subjects, including genetic factors associated with cardiomyopathies, premature vascular dysfunction and related ischemia, metabolic stress, cardio-toxic responses to different agents, and myocarditis. We also highlight the increasing influence of major risk factors that are driving HF in younger patients, such as obesity, diabetes or arterial hypertension.

Structure-based design, optimization of lead, synthesis, and biological evaluation of compounds active against Trypanosoma cruzi

Chagas' disease affects approximately eight million people throughout the world, especially the poorest individuals. The protozoan that causes this disease-Trypanosoma cruzi-has the enzyme cruzipain, which is the main therapeutic target. As no available medications have satisfactory effectiveness and safety, it is of fundamental importance to design and synthesize novel analogues that are more active and selective. In the present study, molecular docking and the in silico prediction of ADMET properties were used as strategies to optimize the trypanocidal activity of the pyrimidine compound ZN3F based on interactions with the target site in cruzipain. From the computational results, eight 4-amino-5-carbonitrile-pyrimidine analogues were proposed, synthesized (5a-f and 7g-h) and, tested in vitro on the trypomastigote form of the Tulahuen strain of T. cruzi. The in silico study showed that the designed analogues bond favorably to important amino acid residues of the active site in cruzipain. An in vitro evaluation of cytotoxicity was performed on L929 mammal cell lines. All derivatives inhibited the Tulahuen strain of T. cruzi and also exhibited lower toxicity to L929 cells. The 5e product, in particular, proved to be a potent, selective (IC50  = 2.79 ± 0.00 μM, selectivity index = 31.3) inhibitor of T. cruzi. The present results indicated the effectiveness of drugs based on the structure of the receptor, revealing the potential trypanocidal of pyrimidines. This study also provides information on molecular aspects for the inhibition of cruzipain.

Treatment with benznidazole and pentoxifylline regulates microRNA transcriptomic profile in a murine model of Chagas chronic cardiomyopathy

Chronic Chagas cardiomyopathy (CCC) is one of the leading causes of morbidity and mortality due to cardiovascular disorders in endemic areas of Chagas disease (CD), a neglected tropical illness caused by the protozoan parasite Trypanosoma cruzi. CCC is characterized by parasite persistence and inflammatory response in the heart tissue, which occur parallel to microRNA (miRNA) alterations. Here, we investigated the miRNA transcriptome profiling in the cardiac tissue of chronically T. cruzi-infected mice treated with a suboptimal dose of benznidazole (Bz), the immunomodulator pentoxifylline alone (PTX), or the combination of both (Bz+PTX), following the CCC onset. At 150 days post-infection, Bz, PTX, and Bz+PTX treatment regimens improved electrocardiographic alterations, reducing the percentage of mice afflicted by sinus arrhythmia and second-degree atrioventricular block (AVB2) when compared with the vehicle-treated animals. miRNA Transcriptome profiling revealed considerable changes in the differential expression of miRNAs in the Bz and Bz+PTX treatment groups compared with the control (infected, vehicle-treated) group. The latter showed pathways related to organismal abnormalities, cellular development, skeletal muscle development, cardiac enlargement, and fibrosis, likely associated with CCC. Bz-Treated mice exhibited 68 differentially expressed miRNAs related to signaling pathways like cell cycle, cell death and survival, tissue morphology, and connective tissue function. Finally, the Bz+PTX-treated group revealed 58 differentially expressed miRNAs associated with key signaling pathways related to cellular growth and proliferation, tissue development, cardiac fibrosis, damage, and necrosis/cell death. The T. cruzi-induced upregulation of miR-146b-5p, previously shown in acutely infected mice and in vitro T. cruzi-infected cardiomyocytes, was reversed upon Bz and Bz+PTX treatment regimens when further experimentally validated. Our results further our understanding of molecular pathways related to CCC progression and evaluation of treatment response. Moreover, the differentially expressed miRNAs may serve as drug targets, associated molecular therapy, or biomarkers of treatment outcomes.

Direct evidence gap on fixed versus adjusted-dose benznidazole for adults with chronic Chagas disease without cardiomyopathy: Systematic review and individual patient data meta-analysis

OBJECTIVES

To determine the comparative efficacy and safety of a fixed dose of benznidazole (BZN) with an adjusted-dose for Trypanosoma cruzi-seropositive adults without cardiomyopathy.

METHODS

We conducted a systematic review and individual participant data (IPD) meta-analysis following Cochrane methods, and the PRISMA-IPD statement for reporting. Randomised controlled trials (RCTs) allocating participants to fixed or adjusted doses of BZN for T. cruzi-seropositive adults without cardiomyopathy were included. We searched (December 2021) Cochrane, MEDLINE, EMBASE, LILACS and trial registries and contacted Chagas experts. Selection, data extraction, risk of bias assessment using the Cochrane tool, and a GRADE summary of finding tables were performed independently by pairs of reviewers. We conducted a random-effects IPD meta-analysis using the one-stage strategy, or, if that was impossible, the two-stage strategy.

RESULTS

Five RCTs (1198 patients) were included, none directly comparing fixed with adjusted doses of BZN. Compared to placebo, BZN therapy was strongly associated with negative qPCR and sustainable parasitological clearance regardless of the type of dose and subgroup analysed. For negative qPCR, the fixed/adjusted rate of odds ratios (ROR^F/A ) was 8.83 (95% CI 1.02-76.48); for sustained parasitological clearance, it was 4.60 (95% CI 0.40-52.51), probably indicating at least non-inferior effect of fixed doses, with no statistically significant interactions by scheme for global and most subgroup estimations. The ROR^F/A for treatment interruption due to adverse events was 0.44 (95% CI 0.14-1.38), probably indicating no worse tolerance of fixed doses.

CONCLUSIONS

We found no direct comparison between fixed and adjusted doses of BZN. However, fixed doses versus placebo are probably not inferior to weight-adjusted doses of BZN versus placebo in terms of parasitological efficacy and safety. Network IPD meta-analysis, through indirect comparisons, may well provide the best possible answers in the near future.

REGISTRATION

The study protocol was registered in PROSPERO (CRD42019120905).

Critical analysis of Chagas disease treatment in different countries

As a result of globalization and constant migratory flows, Chagas disease is now present in almost all continents. The management and treatment of the disease is often influenced by the economic and social context of the societies that host patients. In this manuscript, we aim to provide a comparative review of approaches to patients with Chagas disease in the Americas and Europe.

Use of benznidazole to treat chronic Chagas disease: An updated systematic review with a meta-analysis

Background

Approximately 6 million people worldwide are affected by Chagas disease, with many in the chronic phase of the disease (CCD). It is crucial to evaluate the effectiveness of benznidazole for CCD treatment.

Methods/Principal findings

We updated a meta-analysis published in 2009 up to February 2021, including controlled trials (RCT) and prospective observational studies (OBS) that compared benznidazole vs placebo/no-treatment (P/nT). Main outcomes evaluated were clinical progression (CP) and seroreversion with subgroup analysis performed according to study design and participants’ age. Parasitological response and safety were also described.

We identified 879 articles and selected nine for inclusion (corresponding to eight studies). After adding the nine articles from the previous meta-analysis, 17 studies were analyzed corresponding to 6640 patients. The odds ratio (OR) for seroreversion in children treated with benznidazole vs P/nT was 38.3 (95%CI: 10.7–137) and 34.9 (95%CI: 1.96–624.09) in RCT and OBS, respectively. In adults the OR for seroreversion in OBS was 17.1 (95%CI: 2.3–129.1). CP was only evaluated in adults, where benznidazole did not demonstrate a beneficial effect: OR 0.93 (95%CI: 0.8–1.1) and OR 0.49 (95%CI:0.2–1.2) for RCT and OBS, respectively. Most outcomes were deemed to have a low level of certainty, except for the beneficial effect in children and the low efficacy in adults (moderate certainty).

Conclusions

Benznidazole should be recommended for CCD in children, though this is only based on serological response and a moderate grade of evidence, while in adults benznidazole efficacy remains uncertain. More data on clinical efficacy of benznidazole in CCD is needed in both children and adults.

Chagas disease is a neglected parasitic disease, endemic in Latin America, where it poses a public health problem. Moreover, thanks to population movements, its presence has significantly increased in non-endemic areas, where it has high rates of under-diagnosis. The only two treatments currently available (benznidazole, generally the first choice, and nifurtimox) date from the 1960s and are poorly tolerated. Moreover, there is much uncertainty about their indication, dosage and benefits, especially in chronically infected adult populations. For this reason, we have update a meta-analysis published in 2009 on the effectiveness of benznidazole in chronic Chagas disease, analyzing data from 17 studies involving 6,640 patients. In the pediatric population the indication is well established thanks to some clinical trials carried out in the 1990s and the accumulated clinical experience so far. Most of the recent studies have been performed in adult populations; however, they provide low or very low certainty on the effectiveness of benznidazole except for patients with established cardiomyopathy, where benznidazole didn´t demonstrated benefit. We find that data on the treatment of indeterminate chronic infection are insufficient. Since no new drugs are expected in the near future, it would be desirable to launch trials with clinical outcomes and long follow-up periods to evaluate the efficacy of current drugs for the treatment of the indeterminate chronic Chagas disease.

Sheltered in Stromal Tissue Cells, Trypanosoma cruzi Orchestrates Inflammatory Neovascularization via Activation of the Mast Cell Chymase Pathway

Microangiopathy may worsen the clinical outcome of Chagas disease. Given the obstacles to investigating the dynamics of inflammation and angiogenesis in heart tissues parasitized by Trypanosoma cruzi, here we used intravital microscopy (IVM) to investigate microcirculatory alterations in the hamster cheek pouch (HCP) infected by green fluorescent protein-expressing T. cruzi (GFP-T. cruzi). IVM performed 3 days post-infection (3 dpi) consistently showed increased baseline levels of plasma extravasation. Illustrating the reciprocal benefits that microvascular leakage brings to the host-parasite relationship, these findings suggest that intracellular amastigotes, acting from inside out, stimulate angiogenesis while enhancing the delivery of plasma-borne nutrients and prosurvival factors to the infection foci. Using a computer-based analysis of images (3 dpi), we found that proangiogenic indexes were positively correlated with transcriptional levels of proinflammatory cytokines (pro-IL1β and IFN-γ). Intracellular GFP-parasites were targeted by delaying for 24 h the oral administration of the trypanocidal drug benznidazole. A classification algorithm showed that benznidazole (>24 h) blunted angiogenesis (7 dpi) in the HCP. Unbiased proteomics (3 dpi) combined to pharmacological targeting of chymase with two inhibitors (chymostatin and TY-51469) linked T. cruzi-induced neovascularization (7 dpi) to the proangiogenic activity of chymase, a serine protease stored in secretory granules from mast cells.

New chemotherapy regimens and biomarkers for Chagas disease: the rationale and design of the TESEO study, an open-label, randomised, prospective, phase-2 clinical trial in the Plurinational State of Bolivia

INTRODUCTION

Chagas disease (CD) affects ~7 million people worldwide. Benznidazole (BZN) and nifurtimox (NFX) are the only approved drugs for CD chemotherapy. Although both drugs are highly effective in acute and paediatric infections, their efficacy in adults with chronic CD (CCD) is lower and variable. Moreover, the high incidence of adverse events (AEs) with both drugs has hampered their widespread use. Trials in CCD adults showed that quantitative PCR (qPCR) assays remain negative for 12 months after standard-of-care (SoC) BZN treatment in ~80% patients. BZN pharmacokinetic data and the nonsynchronous nature of the proliferative mammal-dwelling parasite stage suggested that a lower BZN/NFX dosing frequency, combined with standard or extended treatment duration, might have the same or better efficacy than either drug SoC, with fewer AEs.

METHODS AND ANALYSIS

New ThErapies and Biomarkers for ChagaS infEctiOn (TESEO) is an open-label, randomised, prospective, phase-2 clinical trial, with six treatment arms (75 patients/arm, 450 patients). Primary objectives are to compare the safety and efficacy of two new proposed chemotherapy regimens of BZN and NFX in adults with CCD with the current SoC for BZN and NFX, evaluated by qPCR and biomarkers for 36 months posttreatment and correlated with CD conventional serology. Recruitment of patients was initiated on 18 December 2019 and on 20 May 2021, 450 patients (study goal) were randomised among the six treatment arms. The treatment phase was finalised on 18 August 2021. Secondary objectives include evaluation of population pharmacokinetics of both drugs in all treatment arms, the incidence of AEs, and parasite genotyping.

ETHICS AND DISSEMINATION

The TESEO study was approved by the National Institutes of Health (NIH), U.S. Food and Drug Administration (FDA), federal regulatory agency of the Plurinational State of Bolivia and the Ethics Committees of the participating institutions. The results will be disseminated via publications in peer-reviewed journals, conferences and reports to the NIH, FDA and participating institutions.

TRIAL REGISTRATION NUMBER

NCT03981523.

The Chagas disease study landscape: A systematic review of clinical and observational antiparasitic treatment studies to assess the potential for establishing an individual participant-level data platform

Background

Chagas disease (CD), caused by the parasite Trypanosoma cruzi, affects ~6–7 million people worldwide. Significant limitations still exist in our understanding of CD. Harnessing individual participant data (IPD) from studies could support more in-depth analyses to address the many outstanding research questions. This systematic review aims to describe the characteristics and treatment practices of clinical studies in CD and assess the breadth and availability of research data for the potential establishment of a data-sharing platform.

Methodology/Principal findings

This review includes prospective CD clinical studies published after 1997 with patients receiving a trypanocidal treatment. The following electronic databases and clinical trial registry platforms were searched: Cochrane Library, PubMed, Embase, LILACS, Scielo, Clintrials.gov, and WHO ICTRP.

Of the 11,966 unique citations screened, 109 (0.9%) studies (31 observational and 78 interventional) representing 23,116 patients were included. Diagnosis for patient enrolment required 1 positive test result in 5 (4.6%) studies (2 used molecular method, 1 used molecular and serology, 2 used serology and parasitological methods), 2 in 60 (55.0%), 3 in 14 (12.8%) and 4 or more in 4 (3.7%) studies. A description of treatment regimen was available for 19,199 (83.1%) patients, of whom 14,605 (76.1%) received an active treatment and 4,594 (23.9%) were assigned to a placebo/no-treatment. Of the 14,605 patients who received an active treatment, benznidazole was administered in 12,467 (85.4%), nifurtimox in 825 (5.6%), itraconazole in 284 (1.9%), allopurinol in 251 (1.7%) and other drugs in 286 (1.9%). Assessment of efficacy varied largely and was based primarily on biological outcome; parasitological efficacy relied on serology in 67/85 (78.8%) studies, molecular methods in 52/85 (61.2%), parasitological in 34/85 (40.0%), microscopy in 3/85 (3.5%) and immunohistochemistry in 1/85 (1.2%). The median time at which parasitological assessment was carried out was 79 days [interquartile range (IQR): 30–180] for the first assessment, 180 days [IQR: 60–500] for second, and 270 days [IQR: 18–545] for the third assessment.

Conclusions/Significance

This review demonstrates the heterogeneity of clinical practice in CD treatment and in the conduct of clinical studies. The sheer volume of potential IPD identified demonstrates the potential for development of an IPD platform for CD and that such efforts would enable in-depth analyses to optimise the limited pharmacopoeia of CD and inform prospective data collection.

Chagas disease, also known as American trypanosomiasis, is a neglected tropical disease transmitted by triatomine insects, first identified in 1909. Chagas disease affects approximately 6–7 million people globally and is highly prevalent in Latin America where most cases are reported. However, there is increasing evidence that Chagas disease is now an important public health issue outside the “classical” endemic countries due to population migration. Our understanding of Chagas disease, including its pathologies and factors relating to progression, remains to date limited, and is also challenged by lack of diagnosis and highly effective treatment. This systematic review aims to describe studies with Chagas patients receiving antiparasitic treatment. Databases were searched for relevant studies published after 1997, and the results of these searches were screened.

Although a large volume of studies was identified in the review, heterogeneity was observed in study design, diagnostic methods, outcome assessment, and treatment regimens. While this aspect will be a limitation in pooling individual patient data, the volume of data available should allow sufficient comparison to form the basis of guidelines for future studies. The results of this review demonstrate that development of a Chagas disease data platform for clinical research would enable optimisation of existing data to strengthen evidence for the treatment and diagnosis of Chagas disease.

Treatment With Suboptimal Dose of Benznidazole Mitigates Immune Response Molecular Pathways in Mice With Chronic Chagas Cardiomyopathy

Chronic Chagas cardiomyopathy (CCC) is the most frequent and severe form of Chagas disease, a neglected tropical illness caused by the protozoan Trypanosoma cruzi, and the main cause of morbimortality from cardiovascular problems in endemic areas. Although efforts have been made to understand the signaling pathways and molecular mechanisms underlying CCC, the immunological signaling pathways regulated by the etiological treatment with benznidazole (Bz) has not been reported. In experimental CCC, Bz combined with the hemorheological and immunoregulatory agent pentoxifylline (PTX) has beneficial effects on CCC. To explore the molecular mechanisms of Bz or Bz+PTX therapeutic strategies, C57BL/6 mice chronically infected with the T. cruzi Colombian strain (discrete typing unit TcI) and showing electrocardiographic abnormalities were submitted to suboptimal dose of Bz or Bz+PTX from 120 to 150 days postinfection. Electrocardiographic alterations, such as prolonged corrected QT interval and heart parasite load, were beneficially impacted by Bz and Bz+PTX. RT-qPCR TaqMan array was used to evaluate the expression of 92 genes related to the immune response in RNA extracted from heart tissues. In comparison with non-infected mice, 30 genes were upregulated, and 31 were downregulated in infected mice. Particularly, infection upregulated the cytokines IFN-γ, IL-12b, and IL-2 (126-, 44-, and 18-fold change, respectively) and the T-cell chemoattractants CCL3 and CCL5 (23- and 16-fold change, respectively). Bz therapy restored the expression of genes related to inflammatory response, cellular development, growth, and proliferation, and tissue development pathways, most probably linked to the cardiac remodeling processes inherent to CCC, thus mitigating the Th1-driven response found in vehicle-treated infected mice. The combined Bz+PTX therapy revealed pathways related to the modulation of cell death and survival, and organismal survival, supporting that this strategy may mitigate the progression of CCC. Altogether, our results contribute to the better understanding of the molecular mechanisms of the immune response in the heart tissue in chronic Chagas disease and reinforce that parasite persistence and dysregulated immune response underpin CCC severity. Therefore, Bz and Bz+PTX chemotherapies emerge as tools to interfere in these pathways aiming to improve CCC prognosis.

Serum thymidine kinase 1 protein concentration for predicting early progression and monitoring the response to TACE in hepatocellular carcinomas: a network meta-analysis

Aim:

A meta-analysis was conducted to evaluate the clinical significance of serum thymidine kinase 1 protein concentration (STK1p) in distinguishing between hepatocellular carcinomas (HCC) and non-HCC for predicting early progression and monitoring the response to transarterial chemoembolization in HCC.

Materials & methods:

A total of 24 eligible studies were included, containing 1849 HCC patients and 1069 healthy subjects.

Results:

The STK1p level significantly increased from normal controls to benign/pre-HCC and HCC (p < 0.0001). STK1p also increased significantly in sub-malignant groups: control being the lowest, followed consecutively by hepatic hemangioma, hepatitis B virus infection and hepatic cirrhosis (p < 0.05). After 1 month of transarterial chemoembolization treatment, STK1p level declined significantly, by 44.4% (p < 0.0001).

Conclusion:

STK1p is a useful prognostic biomarker in HCC.

There is a need for reliable prognostic biomarkers in liver cancer, to support therapy efforts. In this study we investigated if thymidine kinase 1 in blood could be used to discover patients with hepatocellular carcinoma and show the results of their treatment. The results are based on 1847 hepatocellular carcinoma patients and 1069 healthy people. We conclude that serum thymidine kinase 1 protein concentration is a reliable biomarker in liver cancer.

Reduced Trypanosoma cruzi-specific humoral response and enhanced T cell immunity after treatment interruption with benznidazole in chronic Chagas disease

BACKGROUND

Interruption of benznidazole therapy due to the appearance of adverse effects, which is presumed to lead to treatment failure, is a major drawback in the treatment of chronic Chagas disease.

METHODS

Trypanosoma cruzi-specific humoral and T cell responses, T cell phenotype and parasite load were measured to compare the outcome in 33 subjects with chronic Chagas disease treated with an incomplete benznidazole regimen and 58 subjects treated with the complete regimen, during a median follow-up period of 48 months.

RESULTS

Both treatment regimens induced a reduction in the T. cruzi-specific antibody levels and similar rates of treatment failure when evaluated using quantitative PCR. Regardless of the regimen, polyfunctional CD4+ T cells increased in the subjects, with successful treatment outcome defined as a decrease of T. cruzi-specific antibodies. Regardless of the serological outcome, naive and central memory T cells increased after both regimens. A decrease in CD4+ HLA-DR+ T cells was associated with successful treatment in both regimens. The cytokine profiles of subjects with successful treatment showed fewer inflammatory mediators than those of the untreated T. cruzi-infected subjects. High levels of T cells expressing IL-7 receptor and low levels of CD8+ T cells expressing the programmed cell death protein 1 at baseline were associated with successful treatment following benznidazole interruption.

CONCLUSIONS

These findings challenge the notion that treatment failure is the sole potential outcome of an incomplete benznidazole regimen and support the need for further assessment of the treatment protocols for chronic Chagas disease.

Benznidazole decreases the risk of chronic Chagas disease progression and cardiovascular events: A long-term follow up study

BACKGROUND

Chagas disease (CD) remains an important endemic disease in Latin America. However, CD became globalized in recent decades. The majority of the chronically infected individuals did not receive etiologic treatment for several reasons, among them the most conspicuous is the lack of access to diagnosis. The impact of trypanocidal treatment on CD chronic phase, without cardiac involvement (indeterminate form ICF), is yet to be determined. We aimed to evaluate the effect of trypanocidal treatment with benznidazole (BZN) on the rate of progression to Chagas heart disease in patients with ICF.

METHODS

This is a retrospective cohort observational study including patients with ICF treated with BZN and compared to a group of non-treated patients matched for age, sex, region of origin, and the year of cohort entry. We reviewed the medical charts of all patients followed from May 1987 to June 2020 at the outpatient center of the Evandro Chagas National Institute of Infectious Diseases (INI) of the Oswaldo Cruz Foundation (Fiocruz), Rio de Janeiro, Brazil. Patients' follow-up included at least one annual medical visit and one annual electrocardiogram (ECG). Echocardiographic exams were performed at baseline and during the follow-up. Disease progression from ICF to cardiac form was defined by changes in baseline ECG. Cumulative incidence and the incidence rate were described in the incidence analysis. Cox proportional hazards models were used to estimate hazard ratios and 95% confidence intervals for the association between BZN and CD progression, cardiovascular events or death.

FINDINGS

One hundred and fourteen treated patients met the study inclusion criteria. A comparison group of 114 non-treated patients matched for age, sex, region of origin, and the year of cohort entry was also included, totalizing 228 patients. Most patients included in the study were male (70.2%), and their mean age was 31.3 (+7.4) years. Over a median follow-up of 15.1 years (ranging from 1.0 to 32.4), the cumulative CD progression incidence in treated patients was 7.9% vs. 21.1% in the non-treated group (p = 0.04) and the CD progression rate was 0.49 per 1.000 patients/year in treated patients vs. 1.10 per 1.000 patients/year for non-treated patients (p = 0.02). BZN treatment was associated with a decreased risk of CD progression in both unadjusted (HR 0.46; 95%CI 0.21 to 0.98) and adjusted (HR 0.43; 95%CI 0.19 to 0.96) models and with a decreased risk of occurrence of the composite of cardiovascular events only in the adjusted (HR 0.15; 95%CI 0.03 to 0.80) model. No association was observed between BZN treatment and mortality.

INTERPRETATION

In a long-term follow-up, BZN treatment was associated with a decreased incidence of CD progression from ICF to the cardiac form and also with a decreased risk of cardiovascular events. Therefore, our results indicate that BZN treatment for CD patients with ICF should be implemented into clinical practice.

Benznidazole for the treatment of Chagas disease

INTRODUCTION

Chagas disease affects 6-7 million people, mainly in the Americas, and benznidazole is one of the two therapeutic options available. Trypanocide treatment aims to eliminate the parasite from the body to prevent the establishment or progression of visceral damage, mainly cardiac and/or digestive. Remarkably, it helps interrupt vertical transmission when administered to women of childbearing age.

AREAS COVERED

We discuss the basic and scarce data regarding chemical, pharmacokinetic, and pharmacodynamic structure. We also collect the most important data from previous phase II and III studies, as well as studies currently underway and upcoming. We reflect on the main indications for treatment and its challenges, such as the profile of adverse effects in adults, the pharmaceutical formulations, the search for reliable biomarkers, as well as regulatory aspects and access barriers. Alternative strategies such as shorter regimens, lower doses, and fixed doses are currently being evaluated to improve access and the safety profile of this treatment.

EXPERT OPINION

Benznidazole is likely to continue to be the drug of choice for Chagas disease in the coming years. However, it would probably be with a different treatment scheme.