RESUMO
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 (RORF/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 RORF/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).
Assuntos
Cardiomiopatias , Doença de Chagas , Trypanosoma cruzi , Adulto , Humanos , Lacunas de Evidências , Doença de Chagas/tratamento farmacológicoRESUMO
Chagas disease (CD) still imposes a heavy burden on most Latin American countries. Vector-borne and mother-to-child transmission cause several thousand new infections per year, and at least 5 million people carry Trypanosoma cruzi. Access to diagnosis and medical care, however, is far from universal. Starting in the 1990s, CD-endemic countries and the Pan American Health Organization-World Health Organization (PAHO-WHO) launched a series of multinational initiatives for CD control-surveillance. An overview of the initiatives' aims, achievements, and challenges reveals some key common themes that we discuss here in the context of the WHO 2030 goals for CD. Transmission of T. cruzi via blood transfusion and organ transplantation is effectively under control. T. cruzi, however, is a zoonotic pathogen with 100+ vector species widely spread across the Americas; interrupting vector-borne transmission seems therefore unfeasible. Stronger surveillance systems are, and will continue to be, needed to monitor and control CD. Prevention of vertical transmission demands boosting current efforts to screen pregnant and childbearing-aged women. Finally, integral patient care is a critical unmet need in most countries. The decades-long experience of the initiatives, in sum, hints at the practical impossibility of interrupting vector-borne T. cruzi transmission in the Americas. The concept of disease control seems to provide a more realistic description of what can in effect be achieved by 2030.
Assuntos
Doença de Chagas , Trypanosoma cruzi , Idoso , América/epidemiologia , Animais , Doença de Chagas/epidemiologia , Doença de Chagas/prevenção & controle , Vetores de Doenças , Feminino , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , GravidezRESUMO
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.
Assuntos
Doença de Chagas , América , Doença de Chagas/tratamento farmacológico , Europa (Continente) , HumanosRESUMO
Chagas disease is a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. There is an urgent need for safe, effective, and accessible new treatments since the currently approved drugs have serious limitations. Drug development for Chagas disease has historically been hampered by the complexity of the disease, critical knowledge gaps, and lack of coordinated R&D efforts. This review covers some of the translational challenges associated with the progression of new chemical entities from preclinical to clinical phases of development, and discusses how recent technological advances might allow the research community to answer key questions relevant to the disease and to overcome hurdles in R&D for Chagas disease.
Assuntos
Doença de Chagas , Tripanossomicidas , Trypanosoma cruzi , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Desenvolvimento de Medicamentos , Descoberta de Drogas , Humanos , Doenças Negligenciadas/tratamento farmacológico , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêuticoRESUMO
Chagas disease is a neglected disease caused by Trypanosoma cruzi parasites. Most diagnosis is based on serological tests, but the lack of a gold standard test complicates the measurement of test performance. To overcome this limitation, we used samples from a cohort of well-characterized T. cruzi-infected women to evaluate the reactivity of two rapid diagnostic tests and one enzyme-linked immunosorbent assay (ELISA). Our cohort was derived from a previous study on congenital transmission of T. cruzi and consisted of 481 blood/plasma samples from Argentina (n = 149), Honduras (n = 228), and Mexico (n = 104), with at least one positive T. cruzi PCR. Reactivity of the three tests ranged from 70.5% for the Wiener ELISA to 81.0% for the T-Detect and 90.4% for the Stat-Pak rapid tests. Test reactivity varied significantly among countries and was highest in Argentina and lowest in Mexico. When considering at least two reactive serological tests to confirm seropositivity, over 12% of T. cruzi infection cases from Argentina were missed by serological tests, over 21% in Honduras, and an alarming 72% in Mexico. Differences in test performance among countries were not due to differences in parasitemia, but differences in antibody levels against ELISA antigens were observed. Geographic differences in T. cruzi parasite strains as well as genetic differences among human populations both may contribute to the discrepancies in serological testing. Improvements in serological diagnostics for T. cruzi infections are critically needed to ensure an optimum identification of cases.
Assuntos
Doença de Chagas , Trypanosoma cruzi , Anticorpos Antiprotozoários , Doença de Chagas/diagnóstico , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Testes SorológicosRESUMO
In a pilot study, we showed that the intermittent administration of benznidazole in chronic Chagas disease patients resulted in a low rate of treatment suspension and therapeutic failure, as assessed by quantitative PCR (qPCR) at the end of treatment. Here, a 3-year posttreatment follow-up study of the same cohort of patients is presented. The treatment scheme consisted of 12 doses of benznidazole at 5 mg/kg of body weight/day in two daily doses every 5 days. Parasite load, Trypanosoma cruzi-specific antibodies, and serum chemokine levels were measured prior to treatment and after a median follow-up of 36 months posttreatment by DNA minicircle kinetoplastid and nuclear DNA satellite sequence qPCR methods, conventional serological techniques, a Luminex-based assay with recombinant T. cruzi proteins, and a cytometric bead array. At the end of follow-up, 14 of 17 (82%) patients had negative qPCR findings, whereas three of 17 (18%) had detectable nonquantiï¬able findings by at least one of the qPCR techniques. A decline in parasite-specific antibodies at 12 months posttreatment was confirmed by conventional serological tests and the Luminex assays. Monocyte chemoattractant protein 1 levels increased after treatment, whereas monokine induced by gamma interferon levels decreased. New posttreatment electrocardiographic abnormalities were observed in only one patient who had cardiomyopathy prior to treatment. Together, these data strengthen our previous findings by showing that the intermittent administration of benznidazole results in a low rate of treatment suspension, with treatment efficacy comparable to that of a daily dose of 5 mg/kg for 60 days.
Assuntos
Doença de Chagas , Nitroimidazóis , Tripanossomicidas , Trypanosoma cruzi , Doença de Chagas/tratamento farmacológico , Seguimentos , Humanos , Nitroimidazóis/uso terapêutico , Projetos Piloto , Tripanossomicidas/uso terapêuticoRESUMO
BACKGROUND: Retrospective observational studies suggest that transmission of Trypanosoma cruzi does not occur in treated women when pregnant later in life. The level of parasitemia is a known risk factor for congenital transmission. Benznidazole (BZN) is the drug of choice for preconceptional treatment to reduce parasitic load. The fear of treatment-related side effects limits the implementation of the Argentine guideline recommending BZN 60d/300 mg (or equivalent) treatment of T. cruzi seropositive women during the postpartum period to prevent transmission in a future pregnancy. A short and low dose BZN treatment might reduce major side effects and increase compliance, but its efficacy to reduce T. cruzi parasitic load compared to the standard 60d/300 mg course is not yet established. Clinical trials testing alternative BZN courses among women of reproductive age are urgently needed. METHODS AND DESIGN: We are proposing to perform a double-blinded, non-inferiority randomized controlled trial comparing a short low dose 30-day treatment with BZN 150 mg/day (30d/150 mg) vs. BZN 60d/300 mg. We will recruit not previously treated T. cruzi seropositive women with a live birth during the postpartum period in Argentina, randomize them at 6 months postpartum, and follow them up with the following specific aims: Specific aim 1: to measure the effect of BZN 30d/150 mg compared to 60d/300 mg preconceptional treatment on parasitic load measured by the frequency of positive Polymerase Chain Reaction (PCR) (primary outcome) and by real-time quantitative PCR (qPCR), immediately and 10 months after treatment. Specific aim 2: to measure the frequency of serious adverse events and/or any adverse event leading to treatment interruption. TRIAL REGISTRATION: ClinicalTrials.gov . Identifier: NCT03672487 . Registered 14 September 2018.
Assuntos
Doença de Chagas/tratamento farmacológico , Nitroimidazóis/uso terapêutico , Trypanosoma cruzi/efeitos dos fármacos , Argentina , Doença de Chagas/diagnóstico , Feminino , Humanos , Carga Parasitária , Período Pós-Parto , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Trypanosoma cruzi/genéticaRESUMO
BACKGROUND: The role of trypanocidal therapy in patients with established Chagas' cardiomyopathy is unproven. METHODS: We conducted a prospective, multicenter, randomized study involving 2854 patients with Chagas' cardiomyopathy who received benznidazole or placebo for up to 80 days and were followed for a mean of 5.4 years. The primary outcome in the time-to-event analysis was the first event of any of the components of the composite outcome of death, resuscitated cardiac arrest, sustained ventricular tachycardia, insertion of a pacemaker or implantable cardioverter-defibrillator, cardiac transplantation, new heart failure, stroke, or other thromboembolic event. RESULTS: The primary outcome occurred in 394 patients (27.5%) in the benznidazole group and in 414 (29.1%) in the placebo group (hazard ratio, 0.93; 95% confidence interval [CI], 0.81 to 1.07; P=0.31). At baseline, a polymerase-chain-reaction (PCR) assay was performed on blood samples obtained from 1896 patients; 60.5% had positive results for Trypanosoma cruzi on PCR. The rates of conversion to negative PCR results (PCR conversion) were 66.2% in the benznidazole group and 33.5% in the placebo group at the end of treatment, 55.4% and 35.3%, respectively, at 2 years, and 46.7% and 33.1%, respectively, at 5 years or more (P<0.001 for all comparisons). The effect of treatment on PCR conversion varied according to geographic region: in Brazil, the odds ratio for PCR conversion was 3.03 (95% CI, 2.12 to 4.34) at 2 years and 1.87 (95% CI, 1.33 to 2.63) at 5 or more years; in Colombia and El Salvador, the odds ratio was 1.33 (95% CI, 0.90 to 1.98) at 2 years and 0.96 (95% CI, 0.63 to 1.45) at 5 or more years; and in Argentina and Bolivia, the odds ratio was 2.63 (95% CI, 1.89 to 3.66) at 2 years and 2.79 (95% CI, 1.99 to 3.92) at 5 or more years (P<0.001 for interaction). However, the rates of PCR conversion did not correspond to effects on clinical outcome (P=0.16 for interaction). CONCLUSIONS: Trypanocidal therapy with benznidazole in patients with established Chagas' cardiomyopathy significantly reduced serum parasite detection but did not significantly reduce cardiac clinical deterioration through 5 years of follow-up. (Funded by the Population Health Research Institute and others; ClinicalTrials.gov number, NCT00123916; Current Controlled Trials number, ISRCTN13967269.).
Assuntos
Cardiomiopatia Chagásica/tratamento farmacológico , Nitroimidazóis/uso terapêutico , Tripanossomicidas/uso terapêutico , Adulto , Idoso , Doenças Cardiovasculares/etiologia , Cardiomiopatia Chagásica/complicações , Cardiomiopatia Chagásica/mortalidade , Doença Crônica , Progressão da Doença , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Nitroimidazóis/efeitos adversos , Carga Parasitária , Reação em Cadeia da Polimerase , Modelos de Riscos Proporcionais , Estudos Prospectivos , Falha de Tratamento , Tripanossomicidas/efeitos adversos , Trypanosoma cruzi/genética , Trypanosoma cruzi/isolamento & purificaçãoRESUMO
There is a clinical need to test new schemes of benznidazole administration that are expected to be at least as effective as the current therapeutic scheme but safer. This study assessed a new scheme of benznidazole administration in chronic Chagas disease patients. A pilot study with intermittent doses of benznidazole at 5 mg/kg/day in two daily doses every 5 days for a total of 60 days was designed. The main criterion of response was the comparison of quantitative PCR (qPCR) findings prior to and 1 week after the end of treatment. The safety profile was assessed by the rate of suspensions and severity of adverse effects. Twenty patients were analyzed for safety, while qPCR was tested for 17 of them. The average age was 43 ± 7.9 years; 55% were female. Sixty-five percent of treated subjects showed detectable qPCR results prior to treatment of 1.45 (0.63 to 2.81) and 2.1 (1.18 to 2.78) parasitic equivalents per milliliter of blood (par.eq/ml) for kinetoplastic DNA (kDNA) qPCR and nuclear repetitive sequence satellite DNA (SatDNA) qPCR, respectively. One patient showed detectable PCR at the end of treatment (1/17), corresponding to 6% treatment failure, compared with 11/17 (65%) patients pretreatment (P = 0.01). Adverse effects were present in 10/20 (50%) patients, but in only one case was treatment suspended. Eight patients showed mild adverse effects, whereas moderate reactions with increased liver enzymes were observed in two patients. The main accomplishment of this pilot study is the promising low rate of treatment suspension. Intermittent administration of benznidazole emerges a new potential therapeutic scheme, the efficacy of which should be confirmed by long-term assessment posttreatment.
Assuntos
Doença de Chagas/tratamento farmacológico , Nitroimidazóis/administração & dosagem , Nitroimidazóis/uso terapêutico , Tripanossomicidas/administração & dosagem , Tripanossomicidas/uso terapêutico , Trypanosoma cruzi/efeitos dos fármacos , Adulto , Doença Crônica , DNA de Cinetoplasto/sangue , DNA Satélite/sangue , Esquema de Medicação , Feminino , Seguimentos , Humanos , Fígado/enzimologia , Masculino , Pessoa de Meia-Idade , Nitroimidazóis/efeitos adversos , Projetos Piloto , Reação em Cadeia da Polimerase , Tripanossomicidas/efeitos adversosRESUMO
Chagas disease or American trypanosomiasis is, together with geohelminths, the neglected disease that causes more loss of years of healthy life due to disability in Latin America. Chagas disease, as determined by the factors and determinants, shows that different contexts require different actions, preventing new cases or reducing the burden of disease. Control strategies must combine two general courses of action including prevention of transmission to prevent the occurrence of new cases (these measures are cost effective), as well as opportune diagnosis and treatment of infected individuals in order to prevent the clinical evolution of the disease and to allow them to recuperate their health. All actions should be implemented as fully as possible and with an integrated way, to maximise the impact. Chagas disease cannot be eradicated due because of the demonstrated existence of infected wild triatomines in permanent contact with domestic cycles and it contributes to the occurrence of at least few new cases. However, it is possible to interrupt the transmission of Trypanosoma cruzi in a large territory and to eliminate Chagas disease as a public health problem with a dramatic reduction of burden of the disease.
Assuntos
Doença de Chagas/prevenção & controle , Controle de Insetos , Insetos Vetores , América/epidemiologia , Animais , Doença de Chagas/epidemiologia , Doença de Chagas/transmissão , Humanos , Saúde PúblicaRESUMO
Congenital infection with Trypanosoma cruzi is a global problem, occurring on average in 5% of children born from chronically infected mothers in endemic areas, with variations depending on the region. This presentation aims to focus on and update epidemiological data, research methods, involved factors, control strategy and possible prevention of congenital infection with T. cruzi. Considering that etiological treatment of the child is always effective if performed before one year of age, the diagnosis of infection in pregnant women and their newborns has to become the standard of care and integrated into the surveillance programs of syphilis and human immunodeficiency virus. In addition to the standard tests, polymerase chain reaction performed on blood of neonates of infected mothers one month after birth might improve the diagnosis of congenital infection. Recent data bring out that its transmission can be prevented through treatment of infected women before they become pregnant. The role of parasite genotypes and host genetic factors in parasite transmission and development of infection in foetuses/neonates has to be more investigated in order to better estimate the risk factors and impact on health of congenital infection with T. cruzi.
Assuntos
Doença de Chagas/congênito , Transmissão Vertical de Doenças Infecciosas , Complicações Parasitárias na Gravidez , Doença de Chagas/epidemiologia , Doença de Chagas/prevenção & controle , Feminino , Genótipo , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/prevenção & controle , Fatores de Risco , Trypanosoma cruziRESUMO
INTRODUCTION: Ninety percent of the aboriginal communities of Argentina are located in areas of endemic vectorial transmission of Chagas disease. Control activities in these communities have not been effective. The goal of this research was to explore the role played by beliefs, habits, and practices of Pilaga and Wichi indigenous communities in their interaction with the local health system in the province of Formosa. This article contributes to the understanding of the cultural barriers that affect the communication process between indigenous peoples and their health care providers. METHODS: Twenty-nine open ended interviews were carried out with members of four indigenous communities (Pilaga and Wichi) located in central Formosa. These interviews were used to describe and compare these communities' approach to health and disease as they pertain to Chagas as well as their perceptions of Western medicine and its incarnation in local health practice. RESULTS: Five key findings are presented: 1) members of these communities tend to see disease as caused by other people or by the person's violation of taboos instead of as a biological process; 2) while the Pilaga are more inclined to accept Western medicine, the Wichi often favour the indigenous approach to health care over the Western approach; 3) members of these communities do not associate the vector with the transmission of the disease and they have little awareness of the need for vector control activities; 4) indigenous individuals who undergo diagnostic tests and accept treatment often do so without full information and knowledge; 5) the clinical encounter is rife with conflict between the expectations of health care providers and those of members of these communities. CONCLUSION: Our analysis suggests that there is a need to consider the role of the cultural patterning of health and disease when developing interventions to prevent and control Chagas disease among indigenous communities in Northern Argentina. This is especially important when communicating with these communities about prevention and control. These research findings might also be of value to national and provincial agencies in charge of decreasing the rates of Chagas disease among indigenous populations.
Assuntos
Doença de Chagas/prevenção & controle , Comunicação , Conhecimentos, Atitudes e Prática em Saúde , Acessibilidade aos Serviços de Saúde , Indígenas Sul-Americanos , Antropologia Cultural , Argentina , Humanos , Aceitação pelo Paciente de Cuidados de Saúde , Inquéritos e QuestionáriosRESUMO
The NHEPACHA Iberoamerican Network, founded on the initiative of a group of researchers from Latin American countries and Spain, aims to establish a research framework for Chagas disease that encompasses diagnosis and treatment. For this purpose, the network has created a questionnaire to gather relevant data on epidemiological, clinical, diagnostic, and therapeutic aspects of the disease. This questionnaire was developed based on a consensus of expert members of the network, with the intention of collecting high-quality standardized data, which can be used interchangeably by the different research centers that make up the NHEPACHA network. Furthermore, the network intends to offer a clinical protocol that can be embraced by other researchers, facilitating comparability among published studies, as well as the development of therapeutic response and progression markers.
Assuntos
Doença de Chagas , Doença de Chagas/epidemiologia , Doença de Chagas/tratamento farmacológico , Humanos , América Latina/epidemiologia , Inquéritos e Questionários , Espanha/epidemiologia , Bases de Dados Factuais , Pesquisa Biomédica/normasRESUMO
BACKGROUND: More than six million people worldwide, particularly in vulnerable communities in Latin America, are infected with Trypanosoma cruzi, the causative agent of Chagas disease. Only a small portion have access to diagnosis and treatment. Both drugs used to treat this chronic, neglected infection, benznidazole and nifurtimox, were developed more than 50 years ago, and adverse drug reactions during treatment pose a major barrier, causing 20% of patients to discontinue therapy. Fexinidazole proved efficacious in an earlier, interrupted clinical trial, but the doses evaluated were not well tolerated. The present study evaluated fexinidazole at lower doses and for shorter treatment durations. METHODS: In this randomised, double-blind, phase 2 trial, we included adult patients (18-60 years old) with confirmed T cruzi infection by serology and PCR and without signs of organ involvement. We evaluated three regimens of fexinidazole-600 mg once daily for 10 days (6·0 g total dose), 1200 mg daily for 3 days (3·6 g), and 600 mg daily for 3 days followed by 1200 mg daily for 4 days (6·6 g)-and compared them with a historical placebo control group (n=47). The primary endpoint was sustained negative results by PCR at end of treatment and on each visit up to four months of follow-up. This study is registered with ClinicalTrials.gov, NCT03587766, and EudraCT, 2016-004905-15. FINDINGS: Between Oct 16, 2017, and Aug 7, 2018, we enrolled 45 patients (n=15 for each group), of whom 43 completed the study. Eight (19%) of 43 fexinidazole-treated patients reached the primary endpoint, compared with six (13%) of 46 in the historical control group. Mean parasite load decreased sharply following treatment but rebounded beginning 10 weeks after treatment. Five participants had seven grade 3 adverse events: carpal tunnel, sciatica, device infection, pneumonia, staphylococcal infection, and joint and device dislocation. Two participants discontinued treatment due to adverse events unrelated to fexinidazole. INTERPRETATION: The fexinidazole regimens in this study had an acceptable safety profile but did not prove effective against T cruzi infection. Development of fexinidazole monotherapy for treating T cruzi infection has been stopped. FUNDING: The Drugs for Neglected Diseases initiative.
Assuntos
Doença de Chagas , Nitroimidazóis , Trypanosoma cruzi , Adulto , Humanos , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Resultado do Tratamento , Doença de Chagas/tratamento farmacológico , Nifurtimox/efeitos adversos , Método Duplo-CegoRESUMO
BACKGROUND: Treatment with benznidazole for chronic Chagas disease is associated with low cure rates and substantial toxicity. We aimed to compare the parasitological efficacy and safety of 3 different benznidazole regimens in adult patients with chronic Chagas disease. METHODS: The MULTIBENZ trial was an international, randomised, double-blind, phase 2b trial performed in Argentina, Brazil, Colombia, and Spain. We included participants aged 18 years and older diagnosed with Chagas disease with two different serological tests and detectable T cruzi DNA by qPCR in blood. Previously treated people, pregnant women, and people with severe cardiac forms were excluded. Participants were randomly assigned 1:1:1, using a balanced block randomisation scheme stratified by country, to receive benznidazole at three different doses: 300 mg/day for 60 days (control group), 150 mg/day for 60 days (low dose group), or 400 mg/day for 15 days (short treatment group). The primary outcome was the proportion of patients with a sustained parasitological negativity by qPCR during a follow-up period of 12 months. The primary safety outcome was the proportion of people who permanently discontinued the treatment. Both primary efficacy analysis and primary safety analysis were done in the intention-to-treat population. The trial is registered with EudraCT, 2016-003789-21, and ClinicalTrials.gov, NCT03191162, and is completed. FINDINGS: From April 20, 2017, to Sept 20, 2020, 245 people were enrolled, and 234 were randomly assigned: 78 to the control group, 77 to the low dose group, and 79 to the short treatment group. Sustained parasitological negativity was observed in 42 (54%) of 78 participants in the control group, 47 (61%) of 77 in the low dose group, and 46 (58%) of 79 in the short treatment group. Odds ratios were 1·41 (95% CI 0·69-2·88; p=0·34) when comparing the low dose and control groups and 1·23 (0·61-2·50; p=0·55) when comparing short treatment and control groups. 177 participants (76%) had an adverse event: 62 (79%) in the control group, 56 (73%) in the low dose group, and 59 (77%) in the short treatment group. However, discontinuations were less frequent in the short treatment group compared with the control group (2 [2%] vs 11 [14%]; OR 0·20, 95% CI 0·04-0·95; p=0·044). INTERPRETATION: Participants had a similar parasitological responses. However, reducing the usual treatment from 8 weeks to 2 weeks might maintain the same response while facilitating adherence and increasing treatment coverage. These findings should be confirmed in a phase 3 clinical trial. FUNDING: European Community's 7th Framework Programme.
Assuntos
Doença de Chagas , Nitroimidazóis , Adulto , Humanos , Doença de Chagas/tratamento farmacológico , Método Duplo-Cego , Nitroimidazóis/administração & dosagem , Resultado do TratamentoRESUMO
BACKGROUND: Trypanosoma cruzi has been divided into Discrete Typing Units I and non-I (II-VI). T. cruzi I is predominant in Mexico and Central America, while non-I is predominant in most of South America, including Argentina. Little is known about congenital transmission of T. cruzi I. The specific aim of this study is to determine the rate of congenital transmission of T. cruzi I compared to non-I. METHODS/DESIGN: We are conducting a prospective study to enroll at delivery, 10,000 women in Argentina, 7,500 women in Honduras, and 13,000 women in Mexico. We are measuring transmitted maternal T. cruzi antibodies by performing two rapid tests in cord blood (Stat-Pak, Chembio, Medford, New York, and Trypanosoma Detect, InBios, Seattle, Washington). If at least one of the results is positive, we are identifying infants who are congenitally infected by performing parasitological examinations on cord blood and at 4-8 weeks, and serological follow-up at 10 months. Serological confirmation by ELISA (Wiener, Rosario, Argentina) is performed in cord and maternal blood, and at 10 months. We also are performing T. cruzi standard PCR, real-time quantitative PCR and genotyping on maternal venous blood and on cord blood, and serological examinations on siblings. Data are managed by a Data Center in Montevideo, Uruguay. Data are entered online at the sites in an OpenClinica data management system, and digital pictures of data forms are sent to the Data Center for quality control. Weekly reports allow for rapid feedback to the sites.
Assuntos
Anticorpos Antiprotozoários/sangue , Doença de Chagas/transmissão , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Trypanosoma cruzi/imunologia , Adulto , Argentina , Doença de Chagas/congênito , Doença de Chagas/diagnóstico , Doença de Chagas/prevenção & controle , Feminino , Sangue Fetal/imunologia , Honduras , Humanos , Lactente , Recém-Nascido , México , Gravidez , Complicações Parasitárias na Gravidez/sangue , Complicações Parasitárias na Gravidez/diagnóstico , Estudos Prospectivos , Trypanosoma cruzi/genéticaRESUMO
Currently available drugs against Trypanosoma cruzi infection, which causes 12000 deaths annually, have limitations in their efficacy, safety and tolerability. The evaluation of therapeutic responses to available and new compounds is based on parasite detection in the bloodstream but remains challenging because a substantial proportion of infected individuals have undetectable parasitemia even when using diagnostic tools with the highest accuracy. We characterize parasite dynamics which might impact drug efficacy assessments in chronic Chagas by analyzing pre- and post-treatment quantitative-PCR data obtained from blood samples collected regularly over a year. We show that parasitemia remains at a steady-state independently of the diagnostic sensitivity. This steady-state can be probabilistically quantified and robustly predicted at an individual level. Furthermore, individuals can be assigned to categories with distinct parasitological status, allowing a more detailed evaluation of the efficacy outcomes and adjustment for potential biases. Our analysis improves understanding of parasite dynamics and provides a novel background for optimizing future drug efficacy trials in Chagas disease. Trial Registration: original trial registered with ClinicalTrials.gov, number NCT01489228.
Assuntos
Doença de Chagas , Trypanosoma cruzi , Humanos , Doença de Chagas/parasitologia , Parasitemia/parasitologia , Infecção Persistente , Reação em Cadeia da Polimerase em Tempo Real , Trypanosoma cruzi/genética , Ensaios Clínicos como AssuntoRESUMO
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.
Assuntos
Doença de Chagas/tratamento farmacológico , Tripanossomicidas/administração & dosagem , Trypanosoma cruzi/efeitos dos fármacos , Adolescente , Antiparasitários , Doença de Chagas/parasitologia , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Feminino , Humanos , Masculino , Estudos Observacionais como Assunto , Resultado do Tratamento , Tripanossomicidas/efeitos adversos , Trypanosoma cruzi/genética , Trypanosoma cruzi/fisiologia , Adulto JovemRESUMO
BACKGROUND: Current treatment for Chagas disease with the only available drugs, benznidazole or nifurtimox, has substantial limitations, including long treatment duration and safety and tolerability concerns. We aimed to evaluate the efficacy and safety of new benznidazole monotherapy regimens and combinations with fosravuconazole, in the treatment of Chagas disease. METHODS: We did a double-blind, double-dummy, phase 2, multicentre, randomised trial in three outpatient units in Bolivia. Adults aged 18-50 years with chronic indeterminate Chagas disease, confirmed by serological testing and positive qualitative PCR results, were randomly assigned (1:1:1:1:1:1:1) to one of seven treatment groups using a balanced block randomisation scheme with an interactive response system. Participants were assigned to benznidazole 300 mg daily for 8 weeks, 4 weeks, or 2 weeks, benznidazole 150 mg daily for 4 weeks, benznidazole 150 mg daily for 4 weeks plus fosravuconazole, benznidazole 300 mg once per week for 8 weeks plus fosravuconazole, or placebo, with a 12-month follow-up period. The primary endpoints were sustained parasitological clearance at 6 months, defined as persistent negative qualitative PCR results from end of treatment, and incidence and severity of treatment-emergent adverse events, serious adverse events, and adverse events leading to treatment discontinuation. Primary efficacy analysis was based on the intention-to-treat and per-protocol populations and secondary efficacy analyses on the per-protocol population. Safety analyses were based on the as-treated population. Recruitment is now closed. This trial is registered with ClinicalTrials.gov, NCT03378661. FINDINGS: Between Nov 30, 2016, and July 27, 2017, we screened 518 patients, and 210 were enrolled and randomised. 30 patients (14%) were assigned to each treatment group. All 210 randomised patients were included in the intention-to-treat population, and 190 (90%) were included in the per-protocol population. In the intention-to-treat analysis, only one (3%) of 30 patients in the placebo group had sustained parasitological clearance at 6 months of follow-up. Sustained parasitological clearance at 6 months was observed in 25 (89%) of 28 patients receiving benznidazole 300 mg daily for 8 weeks (rate difference vs placebo 86% [95% CI 73-99]), 25 (89%) of 28 receiving benznidazole 300 mg daily for 4 weeks (86% [73-99]), 24 (83%) of 29 receiving benznidazole 300 mg daily for 2 weeks (79% [64-95]), 25 (83%) of 30 receiving benznidazole 150 mg daily for 4 weeks (80% [65-95]), 23 (85%) of 28 receiving benznidazole 150 mg daily for 4 weeks plus fosravuconazole (82% [67-97]), and 24 (83%) of 29 receiving benznidazole 300 mg weekly for 8 weeks plus fosravuconazole (79% [64-95]; p<0·0001 for all group comparisons with placebo). Six patients (3%) had ten serious adverse events (leukopenia [n=3], neutropenia [n=2], pyrexia, maculopapular rash, acute cholecystitis, biliary polyp, and breast cancer), eight had 12 severe adverse events (defined as interfering substantially with the patient's usual functions; elevated alanine aminotransferase [n=4], elevated gamma-glutamyltransferase [n=2], elevated aspartate aminotransferase [n=1], neutropenia [n=3], leukopenia [n=1], and breast cancer [n=1]), and 15 (7%) had adverse events that led to treatment discontinuation (most of these were in the groups who received benznidazole 300 mg daily for 8 weeks, benznidazole 300 mg once per week for 8 weeks plus fosravuconazole, and benznidazole 150 mg daily for 4 weeks plus fosravuconazole). No adverse events leading to treatment discontinuation were observed in patients treated with benznidazole 300 mg daily for 2 weeks or placebo. There were no treatment-related deaths. INTERPRETATION: Benznidazole induced effective antiparasitic response, regardless of treatment duration, dose, or combination with fosravuconazole, and was well tolerated in adult patients with chronic Chagas disease. Shorter or reduced regimens of benznidazole could substantially improve treatment tolerability and accessibility, but further studies are needed to confirm these results. FUNDING: Drugs for Neglected Diseases initiative (DNDi). TRANSLATION: For the Spanish translation of the abstract see Supplementary Materials section.
Assuntos
Doença de Chagas/tratamento farmacológico , Nitroimidazóis/administração & dosagem , Triazóis/administração & dosagem , Adulto , Bolívia , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Masculino , Nitroimidazóis/efeitos adversos , Carga Parasitária , Resultado do Tratamento , Triazóis/efeitos adversos , Adulto JovemRESUMO
BACKGROUND: Current algorithm for Congenital Chagas Disease (cCD) diagnosis is unsatisfactory due to low sensitivity of the parasitological methods. Moreover, loss to follow-up precludes final serodiagnosis after nine months of life in many cases. A duplex TaqMan qPCR kit for Trypanosoma cruzi DNA amplification was prospectively evaluated in umbilical cord (UCB) and peripheral venous blood (PVB) of infants born to CD mothers at endemic and non-endemic sites of Argentina. METHODS: We enrolled and followed-up 370 infants; qPCR was compared to gold-standard cCD diagnosis following studies of diagnostic accuracy guidelines. FINDINGS: Fourteen infants (3·78%) had cCD. The qPCR sensitivity and specificity were higher in PVB (72·73%, 99·15% respectively) than in UCB (66·67%, 96·3%). Positive and negative predictive values were 80 and 98·73% and 50 and 98·11% for PVB and UCB, respectively. The Areas under the Curve (AUC) of ROC analysis for qPCR and micromethod (MM) were 0·81 and 0·67 in UCB and 0·86 and 0·68 in PVB, respectively. Parasitic loads ranged from 37·5 to 23,709 parasite equivalents/mL. Discrete typing Unit Tc V was identified in five cCD patients and in six other cCD cases no distinction among Tc II, Tc V or Tc VI was achieved. INTERPRETATION: This first prospective field study demonstrated that qPCR was more sensitive than MM for early cCD detection and more accurate in PVB than in UCB. Its use, as an auxiliary diagnostic tool to MM will provide more accurate records on cCD incidence. FUNDING: FITS SALUD 001-CHAGAS (FONARSEC, MINCyT, Argentina) to the Public-Private Consortium (INGEBI-CONICET, INP-ANLIS MALBRAN and Wiener Laboratories); ERANET-LAC-HD 328 to AGS and PICT 2015-0074 (FONCYT, MinCyT) to AGS and FA.