Economic evaluation of treatments for chronic hepatitis B

The aim of this study was to conduct a cost-utility study of adefovir, entecavir, interferon alpha, pegylated interferon alpha, lamivudine and tenofovir for chronic hepatitis B in the context of Brazilian Public Health Care System. A systematic review was carried out for efficacy and safety. Another review was performed to collect utility data and transition probabilities between health states. A Markov model was developed in a time horizon of 40 years with annual cycles for three groups of: HBeAg positive, HBeAg negative, and all patients. These strategies were compared to a fourth group that received no treatment. Discount rates of 5% were applied and sensitivity analyses were performed. Tenofovir offered the best cost-utility ratio for the three evaluated models: U$397, U$385 and U$384 (per QALY, respectively, for HBeAg positive, negative, and all patients). All other strategies were completely dominated because they showed higher costs and lower effectiveness than tenofovir. The sequence of cost-utility in the three models was: tenofovir, entecavir, lamivudine, adefovir, telbivudine, pegylated interferon alpha, and interferon alpha. In the sensitivity analysis, adefovir showed lower cost-utility than telbivudine in some situations. The study has some limitations, primarily related to the creation of scenarios and modeling. In this study, tenofovir presented the best cost-utility ratio. The results obtained in this study will be valuable in decision-making and in the review of the clinical protocol, mainly involving the allocation of available resources for health care.

Antivirais incorporados no Brasil para hepatite B cronica: analise de custo-efetividade / Antivirales incorporados en Brasil para hepatitis B cronica: analisis de costo-efectividad / Incorporated antivirals for chronic hepatitis B in Brazil: a cost-effectiveness analysis

OBJETIVO Avaliar o custo-efetividade de diferentes tratamentos medicamentosos para hepatite B crônica entre pacientes adultos. MÉTODOS Utilizando modelo de Markov, construiu-se coorte hipotética de 40 anos para pacientes HBeAg-positivo ou HBeAg-negativo. Foram comparados os usos de adefovir, entecavir, tenofovir e lamivudina (com terapia de resgate em caso de resistência viral) para tratamento de pacientes adultos com hepatite B crônica, virgens de tratamento, com elevados níveis de alanina aminotransferase, sem evidência de cirrose e sem coinfecção por HIV. Valores para custo e efeito foram obtidos da literatura. A medida do efeito foi expressa em anos de vida ganhos (AVG). Taxa de desconto de 5% foi aplicada. Análise de sensibilidade univariada foi conduzida para avaliar incertezas do modelo. RESULTADOS O tratamento inicial com entecavir ou tenofovir apresentou melhores resultados clínicos. As menores razões custo-efetividade foram de entecavir para pacientes HBeAg-positivo (R$ 4.010,84/AVG) e lamivudina para pacientes HBeAg-negativo (R$ 6.205,08/AVG). Para pacientes HBeAg-negativo, a razão custo-efetividade incremental de entecavir (R$ 14.101,05/AVG) está abaixo do limiar recomendado pela Organização Mundial da Saúde. Análise de sensibilidade mostrou que variação nos custos dos medicamentos pode tornar tenofovir alternativa custo-efetiva tanto para pacientes HBeAg-positivo quanto para HBeAg-negativo. CONCLUSÕES Entecavir é alternativa recomendada para iniciar o tratamento de pacientes com hepatite B crônica no Brasil. Contudo, se houver redução no custo de tenofovir, esta pode se tornar alternativa mais custo-efetiva. .

OBJETIVO Evaluar el costo-efectividad de diferentes tratamientos medicamentosos para hepatitis B crónica entre pacientes adultos. MÉTODOS Utilizando el modelo de Markov, se construyó cohorte hipotética de 40 años para pacientes HBeAg-positivo o HBeAg-negativo. Se compararon los usos de adefovir, entecavir, tenofovir y lamivudina (con terapia de rescate en caso de resistencia viral) para tratamiento de pacientes adultos con hepatitis B crónica, vírgenes de tratamiento, con elevados niveles de alanina aminotransferasa, sin evidencia de cirrosis y sin coinfección por VIH. Valores para costo y efecto fueron obtenidos de la literatura y efecto en años de vida ganados (AVG). Tasa de descuento de 5% fue aplicada. Análisis de sensibilidad univariado fue conducido para evaluar incertidumbres del modelo. RESULTADOS El tratamiento inicial con entecavir o tenofovir presentó mejores resultados clínicos. Los menores cocientes costo-efectividad fueron de entecavir para pacientes HBeAg-positivo (R.010,84/AVG) y lamivudina para pacientes HBeAg-negativo (R.205,08/AVG).Para pacientes HBeAg-negativo, el cociente costo-efectividad incrementado de entecavir (R.101,05/AVG) está por debajo del límite recomendado por la Organización Mundial de la Salud. El análisis de sensibilidad mostró que la variación en los costos de los medicamentos puede tornar tenofovir una alternativa costo-efectiva tanto para pacientes HBeAg-positivo como para los HBeAg-negativo. CONCLUSIONES Entecavir es una alternativa recomendada para iniciar el tratamiento de pacientes con hepatitis B crónica en Brasil. Sin embargo, al haber reducción en el costo de tenofovir, éste puede convertirse en una alternativa más costo-efectiva. .

OBJECTIVE To evaluate the cost-effectiveness of different drug therapies for chronic hepatitis B in adult patients. METHODS Using a Markov model, a hypothetical cohort of 40 years for HBeAg-positive or HBeAg-negative patients was constructed. Adefovir, entecavir, tenofovir and lamivudine (with rescue therapy in cases of viral resistance) were compared for treating adult patients with chronic hepatitis B undergoing treatment for the first time, with high levels of alanine aminotransferase, no evidence of cirrhosis and without HIV co-infection. Values for cost and effect were obtained from the literature, and expressed in effect on life years (LY). A discount rate of 5% was applied. Univariate sensitivity analysis was conducted to assess model uncertainties. RESULTS Initial treatment with entecavir or tenofovir showed better clinical outcomes. The lowest cost-effectiveness ratio was for entecavir in HBeAg-positive patients (R$ 4,010.84/LY) and lamivudine for HBeAg-negative patients (R$ 6,205.08/LY). For HBeAg-negative patients, the incremental cost-effectiveness ratio of entecavir (R$ 14,101.05/LY) is below the threshold recommended by the World Health Organization. Sensitivity analysis showed that variation in the cost of drugs may make tenofovir a cost-effective alternative for both HBeAg-positive and HBeAg-negative patients. CONCLUSIONS Entecavir is the recommended alternative to start treating patients with chronic hepatitis B in Brazil. However, if there is a reduction in the cost of tenofovir, it can become a cost-effective alternative. .

Custo-efetividade dos análogos de nucleosídeos/nucleotídeos para hepatite crônica B / Cost-effectiveness of nucleoside/nucleotide analogues in chronic hepatitis B / Costo-efectividad de los análogos de nucleósidos/nucleótidos para hepatitis crónica B

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OBJECTIVE: To conduct a cost-effectiveness analysis of drug alternatives with rescue therapy in case of relapse due to viral resistance for the treatment of patients with chronic hepatitis B (CHB). METHODS: Hypothetical cohort of patients with CHB, HBeAg-negative, without clinical or histological evidence of cirrhosis, detectable HBV DNA, histological diagnosis of the disease, positive serum HBsAg for longer than six months, high levels of alanine aminotransferase (ALT) (twice as high as the upper limit of normality) and mean age of 40 years. A Markov model was developed for chronic hepatitis B (HBeAg- negative) with a 40-year time horizon. Costs and benefits were discounted at 5%. Annual rates of disease progression, costs due to complications and the efficacy of medicines were obtained from the literature. One-way and probabilistic sensitivity analysis evaluated uncertainties. RESULTS: Initiation of treatments with entecavir resulted in an increase of 0.35 discounted life-years gained compared to lamivudine. The incremental cost-effectiveness ratio was R$16,416.08 per life-years gained. In the sensitivity analysis, the incremental cost-effectiveness ratio was more sensitive to variation in the probability of transition from chronic hepatitis B to compensated cirrhosis, discount rate and medicine prices (± 10%). In the probabilistic sensitivity analysis, the acceptability curve showed that beginning treatment with entecavir was the most cost-effective alternative in comparison with the use of lamivudine. CONCLUSIONS: The availability of entecavir is economically attractive as part of early treatment for patients with chronic hepatitis B without HIV co-infection.

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Comparison of entecavir and adefovir for the treatment of chronic hepatitis B

The results of several new clinical trials that compared the effectiveness of entecavir (ETV) treatment with that of adefovir (ADV) treatment in patients with chronic hepatitis B (CHB) were published in recent years. However, the numbers of patients included in these clinical trials were too small to draw a clear conclusion as to whether ETV is more effective than ADV. Therefore, a new meta-analysis was needed to compare ETV with ADV for the treatment of CHB. A search of the Cochrane Central Register of Controlled Trials (CCTR), MEDLINE, the Science Citation Index, Embase, the China National Knowledge Infrastructure (CNKI), and the Wanfang Database for relevant studies published between 1966 and 2010 was performed. Trials comparing the use of ETV and ADV for the treatment of CHB were assessed. Of the 2,358 studies screened, 13 randomized controlled clinical trials comprising 1,230 patients (ETV therapy, 621; ADV therapy, 609) were analyzed. The serum hepatitis B virus (HBV) DNA clearance rate obtained in patients treated with ETV was significantly higher than that in patients treated with ADV at the 24th and 48th weeks of treatment (24 weeks: 59.6% vs. 31.8%, relative risk [RR], 1.82, 95% CI: 1.49-2.23; 48 weeks: 78.3% vs. 50.4%, RR, 1.61, 95% CI: 1.32-1.96). The serum HBeAg clearance rate, the HBeAg seroconversion rate, and the ALT normalization rate obtained for patients treated with ETV were also higher than the corresponding values for patients treated with ADV at the 48th week of treatment. The safety profiles were similar between patients treated with ETV and those treated with ADV. The evidence reviewed in this meta-analysis suggests that patients with hepatitis B have a greater likelihood of achieving a viral response and a biomedical response when treated with ETV than when treated with ADV.

Eficácia do adefovir dipivoxil, entecavir e telbivudina para o tratamento da hepatite crônica B: revisão sistemática / The efficacy of adefovir dipivoxil, entecavir and telbivudine for chronic hepatitis B treatment: a systematic review

INTRODUÇÃO: A hepatite crônica B é uma das doenças infecciosas mais frequentes no mundo e constitui um grave problema de saúde pública MÉTODOS: Para avaliar a eficácia dos análogos de núcleosídeo/nucletídeo utilizados no seu tratamento (adefovir dipivoxil, entecavir e telbivudina) foi conduzida uma revisão sistemática de ensaios clínicos randomizados. Foram consultadas, dentre outras, as bases de dados PubMed e LILACS RESULTADOS: Foram selecionados 29 artigos entre os publicados de janeiro/1970 até dezembro/2009 CONCLUSÕES: Todos os análogos de núcleosídeo/nucletídeo apresentam eficácia superior ou similar à lamivudina. O entecavir pode ser indicado para o tratamento da hepatite B crônica como alternativa à lamivudina em pacientes HBeAg positivo e negativo virgens de tratamento, considerando seu baixo potencial de resistência viral. A adição de adefovir à lamivudina apresentou bons resultados em pacientes resistentes à lamivudina. O uso de entecavir e telbivudina nesses pacientes apresenta risco de resistência cruzada. Telbivudina é um dos mais recentes antivirais disponíveis, mas resistência antiviral já documentada representa limitação ao seu uso como opção terapêutica à lamivudina. Eventos adversos aos análogos de núcleosídeo/nucletídeo foram similares em características, gravidade e incidência quando comparados à lamivudina e placebo.

INTRODUCTION: Chronic hepatitis B is one of the most frequent infectious disease in the world and represents a serious problem of public health METHODS: A systematic review of randomized clinical trials was conducted to evaluate the efficacy of the nucleoside/nucleotide analogues (adefovir, entecavir and telbivudine) used for the treatment of chronic hepatitis B. The databases PubMed and LILACS were consulted, among others RESULTS: Twenty nine articles published between January/1970 to December/2009 were selected CONCLUSIONS: All nucleoside/nucleotide analogues demonstrate upper or similar efficacy to lamivudine. The entecavir can be appropriate for patients with chronic hepatitis B, HBeAg positive and negative treatment-naive as alternative to lamivudine, considering its low potential of viral resistance. The addition of adefovir to lamivudine presented good results in lamivudine resistant patients. The use of entecavir and telbivudine in those patients presents risk of crossed resistance. TBV is one of the most recent antivirals available, but antiviral resistance already documented represents limitation to its use as therapeutic option to LAM. Adverse events of nucleoside/nucleotide analogues were similar in characteristics, gravity and incidence when compared to the lamivudina and placebo.

In vitro plant regeneration system for common bean (Phaseolus vulgaris): effect of N6-benzylaminopurine and adenine sulphate / Sistema de regeneración de plantas in vitro para el frijol común (Phaseolus vulgaris): efecto del frl sulfato N6-bencilaminopurina y adenina

A method for regeneration of the commercially important common bean (Phaseolus vulgaris ) using N6-benzylaminopurine(BAP) and adenine sulphate (AS) was established. Embryogenic axes of the Costa Rican common bean cultivars Bribrí, Brunca, Guaymí, Huetar and Telire were cultured on Murashige and Skoog medium supplemented with 100 mgl-1 myo-inositol, 1 mgl-1 thiamine, 30 gl-1 sucrose, BAP (0, 5 and 10 mgl-1), AS (0, 20 and 40 mgl-1) and 8 gl-1 agar. Regardless of the concentration of BAP and AS in the induction medium, the number of shoots and leaves differed significantly among the common bean cultivars evaluated. The higher average of shoots was obtained for Brunca > Telire > Bribrí > Guaymí > Huetar. Moreover, independently of the cultivar, the induction medium supplemented with 5 mgl-1 BAP and 20 or 40 mgl-1 AS resulted in the higher average of shoots formation. Culture of Bribrí, Brunca, Guaymí, Huetar and Telire embryogenic axes on induction medium supplemented with different BAP and AS resulted in a differential response. Successful acclimatization of common bean in vitro plants were achieved in the greenhouse, and plants appeared morphologically normal. The regeneration system developed in this investigation for this important crop could be a useful tool for the genetic modification through mutagenesis or genetic transformation.

In vitro regeneration and genetic fidelity of Tigridia pavonia (L. f.) DC

Plants of Tigridia pavonia (L.f.) DC were regenerated from twin-scaling explants cultured on Murashige and Skoog and N6 basal medium. The highest formation of shoots per responding explant was obtained on N6 medium supplemented with 4.5 uM 2,4-dichlorophenoxy acetic acid in combination with 2.2 uM benzylaminopurine. Shoots rooted readily on N6 basal medium supplemented with 1 g I-1 activated charcoal and 2.6 uM naphtalenacetic acid. The rooted shoots achieved 100 percent survival. Inter Simple Sequence Repeat analysis was carried out to check for possible genetic alterations in plants obtained after two consecutive subcultures. The results revealed that the recovered plants did not exhibit any type of polymorphism.

Tratamiento de la hepatitis crónica viral / Treatment of chronic viral hepatitis

Gracias a los actuales conocimientos sobre la patogénesis de la hepatitis crónica viral y a la contemporánea disponibilidad de un amplio espectro de fármacos capaces de modular el sistema inmunitario y de interferir en la replicación viral, es hoy posible plantear una estrategia terapéutica más eficaz con respecto al esquema empírico y desilusionante del pasado. Se destaca la importancia del diagnóstico etiológico de la infección viral y del daño hepático para la elección del tratamiento más apropiado para cada uno de los pacientes, considerando los factores que favorecen o desfavorecen una buena respuesta terapéutica. Entre los fármacos disponibles el Interferon ha demostrado la mayor eficacia, pero su empleo es limitado a un grupo particular de pacientes. Tratamientos combinados han dado resultados interesantes en este último tiempo en pacientes refractarios al Interferon Alfa