Resistencia transmitida de VIH-1 en pacientes sin exposición a tratamiento antirretroviral: Guatemala / Transmitted HIV-1 resistance in patients without exposure to antiretroviral treatment: Guatemala / Resistência transmitida ao HIV-1 em pacientes sem exposição ao tratamento antirretroviral: Guatemala

El objetivo del estudio fue describir los niveles de resistencia transmitida de VIH-1 en adultos atendidos en Unidades de Atención Integral de Guatemala. El estudio incluyó registros de 185 pacientes adultos VIH-1 positivo, de reciente diagnóstico sin antecedente de uso de TAR, de noviembre del 2019 a noviembre del 2020. El análisis se realizó en el software DeepChek® v2.0, para la clasificación de la resistencia se siguió el algoritmo de Stanford HIVdb (v9.4 - 07/12/2022). Se encontró 18.4% (IC 95% 13.1 - 24.7%) de resistencia general a alguna familia de ARVs. Se evidenció 15.1% (IC 95% 10.3 - 21.1%) de resistencia individual a la familia de INNTR afectando principalmente a NVP y EFV; 2.2% (IC 95% 0.6 - 5.4%) de resistencia a INTR, mayormente a FTC/3TC; y 2.7% (IC 95% 0.9 - 6.2%) de resistencia intermedia y baja los IP NFV y LPV/r. Tres casos presentaron resistencia múltiple a los INTR + INNTR. Las mutaciones más frecuentemente encontradas fueron K103N (41.2%), M184V/I (8.8%) y M46I (5.9%). La elevada resistencia transmitida del VIH-1 en pacientes atendidos en distintas Unidades de Atención Integral del VIH, demuestra la importancia de analizar periódicamente la tendencia de la resistencia en personas que no han estado expuestas a ARVs, lo cual a su vez es un marcador indirecto de presencia de resistencia adquirida en el país, datos que evidencian la necesidad de acciones e intervenciones prontas y efectivas dado su impacto en la salud pública.

The objective of this study was to describe the levels of transmitted HIV-1 resistance in patients with a recent HIV diagnosis before starting ART, treated in Comprehensive Care Units in Guatemala during the years 2019 and 2020. The study included records of 185 HIV-positive adult patients, recently diagnosed with HIV without a history of ART use. The analysis was carried out in the DeepChek® v2.0 software, the Stanford HIVdb algorithm (v9.4 - 07/12/2022) was followed to classify resistance. 18.4% (95% CI 13.1 - 24.7%) of general resistance to some family of ARVs was found. There was evidence of 15.1% (95% CI 10.3 - 21.1%) of individual resistance to the NNRTI family, mainly affecting NVP and EFV; 2.2% (95% CI 0.6 - 5.4%) resistance to INTR, mostly to FTC/3TC; and 2.7% (95% CI 0.9 - 6.2%) of intermediate and low resistance IP NFV and LPV/r. Three cases presented multiple resistance to NRTIs + NNRTIs. The most frequently found mutations were K103N (41.2%), M184V/I (8.8%) and M46I (5.9%). The high transmitted resistance of HIV-1 in patients treated in different Comprehensive HIV Care Units demonstrates the importance of periodically analyzing the trend of resistance in people who have not been exposed to ARVs, which in turn is an indirect marker. of the presence of acquired resistance in the country, data that demonstrate the need for prompt and effective actions and interventions given its impact on public health.

O objetivo deste estudo foi descrever os níveis de resistência transmitida ao HIV-1 em adultos tratados em Unidades de Cuidados Integrais na Guatemala. O estudo incluiu prontuários de 185 pacientes adultos HIV-1 positivos, recentemente diagnosticados sem histórico de uso de TARV, no período de novembro de 2019 a novembro de 2020. A análise foi realizada no software DeepChek® v2.0, para classificação da resistência, O algoritmo Stanford HIVdb (v9.4 - 07/12/2022) foi seguido. Foi encontrada 18.4% (IC 95% 13.1 - 24.7%) de resistência geral a alguma família de ARVs. Houve evidência de 15.1% (IC 95% 10.3 - 21.1%) de resistência individual à família de NNRTI, afetando principalmente NVP e EFV; 2.2% (IC 95% 0.6 - 5.4%) resistência ao INTR, principalmente ao FTC/3TC; e 2.7% (IC 95% 0.9 - 6.2%) de resistência intermediária e baixa ao IP NFV e LPV/r. Três casos apresentaram resistência múltipla a NRTIs + NNRTIs. As mutações mais frequentemente encontradas foram K103N (41.2%), M184V/I (8.8%) e M46I (5.9%). A elevada resistência transmitida do HIV-1 em pacientes atendidos em diferentes Unidades de Cuidados Integrados ao HIV demonstra a importância de analisar periodicamente a tendência de resistência em pessoas que não foram expostas aos ARVs, o que por sua vez é um marcador indireto da presença de ARVs adquiridos. resistência no país, dados que demonstram a necessidade de ações e intervenções rápidas e eficazes dado o seu impacto na saúde pública.

Novel fluoronucleoside analog NCC inhibits lamivudine-resistant hepatitis B virus in a hepatocyte model

ABSTRACT Antiviral drug resistance is the most important factor contributing to treatment failure using nucleos(t)ide analogs such as lamivudine for chronic infection with hepatitis B virus (HBV). Development of a system supporting efficient replication of clinically resistant HBV strains is imperative, and new antiviral drugs are needed urgently to prevent selection of drug-resistant HBV mutants. A novel fluorinated cytidine analog, NCC (N-cyclopropyl-4′-azido-2′-deoxy-2′-fluoro-β-d-cytidine), was recently shown to strongly inhibit human HBV in vitro and in vivo. This study was designed to evaluate the antiviral activity of NCC against lamivudine-resistant HBV. We generated a stable cell line encoding the major pattern of lamivudine-resistant mutations rtL180M/M204V and designated it "HepG2.RL1". Immuno-transmission electron microscopic examination and enzyme-linked immunosorbent assay were used to detect secretion of HBV-specific particles and antigens. Quantification of extracellular DNA and intracellular DNA of HepG2.RL1 cells by quantitative real-time polymerase chain reaction revealed >625-fold and >5556-fold increases in the 50% inhibitory concentration of lamivudine, respectively, compared with that for the wild-type virus. The results showed that NCC inhibited DNA replication and HBeAg production in wild-type or lamivudine-resistant HBV in a dose-dependent manner. In conclusion, screening for antiviral compounds active against lamivudine-resistant HBV can be carried out with relative ease using hepG2.RL1 cells. NCC is a potential antiviral agent against wild-type HBV and clinical lamivudine-resistant HBV and deserves evaluation for the treatment of HBV infection.

HCMV UL97 phosphotransferase gene mutations may be associated with antiviral resistance in immunocompromised patients in Belém, PA, Northern Brazil

Abstract INTRODUCTION: Human cytomegalovirus is one of the causes of opportunist infections in immunocompromised patients, and is triggered by factors such as state of viral latency, weakened immune responses, and development of antiviral resistance to ganciclovir, the only drug offered by the public health system in Brazil to treat the infection. The goal of this study was to identify mutations that may be associated with antiviral resistance in immunocompromised patients. METHODS: Molecular analysis was performed in 82 blood samples and subjected to genomic DNA extraction by a silica-based method. Three sequences of the HCMV UL97 gene, which encodes a phosphotransferase protein required for activation of ganciclovir, were amplified by polymerase chain reaction. Pyrosequencing methods were applied to one external 2096-bp segment DNA and two internal sequences between nucleotides 1087 to 1828 to detect mutations in this gene. RESULTS: Approximately 10% of sequences contained mutations between nucleotides 377 and 594, in conserved regions of the UL97 gene, leading to amino acid changes. Eleven coding mutations were identified, including changes leading to amino acid substitutions, E596K and S604F, which were observed in 100% of samples and are described for the first time in Brazil. In addition, one mutation (A594V) that is associated with ganciclovir resistance was detected in a kidney transplant patient. CONCLUSIONS: Further studies to detect mutations associated with HCMV resistance to antiviral drugs are required to demonstrate the need to increase the variety and availability of drugs used to treat viral infections in the public health care system in Brazil.

Prevalencia de resistencia a los anti-retrovirales en niños y adolescentes uruguayos infectados con el virus de la inmunodeficiencia humana en el Centro de Referencia VIH-SIDA. Centro Hospitalario Pereira Rossell. Montevideo-Uruguay / Prevalence of antiretroviral resistance in Uruguayan children and adolescents infected with the human immunodeficiency virus in the Reference Center HIV-AIDS. Centro Hospitalario Pereira Rossell, Montevideo, Uruguay

Resumen Introducción: A nivel mundial, la tasa global de resistencia primaria y secundaria a los anti-retrovirales (ARV) es de 15 y 40%, respectivamente. Se desconoce su prevalencia en Uruguay. Objetivo: Conocer la prevalencia de resistencia a los ARV en niños y adolescentes uruguayos bajo 15 años de edad infectados con VIH que se controlan en el Centro Hospitalario Pereira Rossell entre 2008 y 2016. Objetivos específicos: Cuantificar mutaciones de resistencia primarias y secundarias e identificar variables asociadas a resistencias; describir si el resultado del test de resistencia contribuyó a lograr una carga viral (CV) indetectable. Metodología: Descriptivo observacional, seguimiento longitudinal. Se incluyeron menores de 15 años con test de resistencia entre 1 de enero de 2008 y 15 de diciembre de 2016. Variables maternas y del niño. Resultados: Se incluyeron 56 niños. Tenían test de resistencia previo al inicio TARV 36 niños (64%) y por fallo terapéutico 20 (36%). La resistencia total fue 28,6% (16 niños): cuatro (11,1%) con mutaciones primarias y 12 (60%) secundarias. El test modificó el plan ARV en 15 (26,7%) de los 56 niños. El cambio logró CV indetectable a los seis meses en ocho casos. El cambio de TARV no se asoció con sida o muerte. Discusión: Los estudios de prevalencia son útiles para la toma de decisiones sobre la selección inicial de ARV. La prevalencia de mutaciones primarias fue similar a la publicada, mientras que la secundaria fue mayor.

Background: Primary and secondary antiretroviral (ARV) resistance rates of 15 and 40% respectively have been reported in worldwide. Its prevalence in Uruguay is unknown. Aim: To know the prevalence of ARV resistance in Uruguayan children under 15 years old infected with HIV that are controlled in the Centro Hospitalario Pereira Rossell between 2008 and 2016. Specific objectives: Quantify primary and secondary mutations, to identify variables associated with resistance; to describe if the result of the resistance test contributed to achieve undetectable viral load (VL). Methodos: Observational descriptive, longitudinal follow-up. Only children under 15 years with resistance test done between January first 2008 and December 31th 2016 were included in the study. Maternal and child variables. Results: Fifty six children were included. 36 children (64%) had resistance tests prior to the initiation of ART and the other 20 children (36%) due to therapeutic failure. Total resistance: 28.6% (16 children); 4 (11.1%) children with primary mutations and 12 (60%) secondary mutations. The test result changed the ARV plan in 15 (26.7%) of the 56 children. The change achieved undetectable CV in 8 children at month 6. The ART change was not associated with AIDS or death. Discussion: Prevalence studies are useful in making decisions about initial ARV treatment. The prevalence of primary mutations was similar to that published, while secondary prevalence was higher.

Resistencia de HIV-1 a drogas antirretrovirales en gestantes del área metropolitana de Buenos Aires / HIV-1 resistance to antiretroviral drugs in pregnant women from Buenos Aires metropolitan area

Se determinó la frecuencia de mutaciones asociadas a resistencia de HIV-1 a antirretrovirales en embarazadas del área metropolitana de Buenos Aires, 2008-2014. Se incluyeron 136 mujeres con carga viral ≥ 500 copias/ml: 77 (56.6%) eran naïve; las otras 59 (43.4%) eran expuestas, ya sea con tratamiento en curso (n: 24) o previo (n: 35). Se realizó análisis de resistencia genotípica basal en plasma de pacientes naïve y con experiencia de tratamiento antirretroviral. Las mutaciones se identificaron según las listas de la Organización Mundial de la Salud y la International Antiviral Society, respectivamente. Se comparó la frecuencia de mutaciones detectadas en los subperíodos 2008-2011 vs. 2012-2014. Un total de 37 (27.2%) mujeres presentaron ≥ 1 mutación asociada a resistencia: 25/94 (26.5%) en 2008-2011 y 12/42 (28.5%) en 2012-2014 (p > 0.05). Entre las naïve, 15 (19.5%) tenían ≥ 1 mutación: 10/49 (20.4%) en el subperíodo 2008-2011 y 5/28 (17.8%) en 2012-2014 (p > 0.05). Las mutaciones encontradas en pacientes naïve estuvieron asociadas a inhibidores no nucleosídicos de la transcriptasa reversa, y, como en estudios anteriores, K103N fue la más frecuente a lo largo de todo el período. Entre las pacientes expuestas, 22/59 (37.3%) presentaron ≥ 1 mutación asociada a resistencia. Este estudio demuestra una alta frecuencia de mutaciones asociadas a resistencia que se mantuvo estable a lo largo del período. Los niveles detectados sugieren una mayor circulación en nuestro medio de cepas de HIV-1 resistentes a antirretrovirales con respecto a los niveles previamente observados en Argentina.

The study aimed to determine the prevalence of antiretroviral resistance associated mutations in HIV-1 infected pregnant woman treated in Buenos Aires metropolitan area (period 2008-2014). A total of 136 women with viral load ≥ 500 copies/ml were included: 77 (56.6%) were treatment-naïve and 59 (43.4%) were antiretroviral-experienced patients either with current (n: 24) or previous (n = 35) antiretroviral therapy. Genotypic baseline resistance was investigated in plasma of antiretroviral-naïve patients and antiretroviral-experienced patients. The resistance mutations were identified according to the lists of the World Health Organization and the International Antiviral Society, respectively. Frequencies of resistance associated mutations detected in 2008-2011 and 2012-2014 were compared. A total of 37 (27.2%) women presented at least one resistance associated mutation: 25/94 (26.5%) in 2008-2011 and 12/42 (28.5%) in 2012-2014 (p > 0.05). Among naïves, 15 (19.5%) had at least one mutation: 10/49 (20.4%) in the period 2008-2011 and 5/28 (17.8%) in 2012-2014 (p > 0.05). The resistance mutations detected in naïves were associated with non nucleoside reverse transcriptase inhibitors, being K103N the most common mutation in both periods. In antiretroviral experienced patients, 22/59 (37.3%) had at least one resistance mutation. This study demonstrates a high frequency of resistance associated mutations which remained stable in the period analyzed. These levels suggest an increased circulation of HIV-1 antiretroviral resistant strains in our setting compared to previous reports from Argentina.

Comparison of tenofovir plus lamivudine versus tenofovir monotherapy in patients with lamivudine-resistant chronic hepatitis B

BACKGROUND/AIMS: Tenofovir disoproxil fumarate (TDF) exhibits similar antiviral efficacy against treatment-naïve and lamivudine (LAM)-resistant chronic hepatitis B (CHB). However, there are few clinical reports on the antiviral effects of TDF-LAM combination therapy compared to TDF monotherapy in patients with LAM-resistant CHB. METHODS: We investigated the antiviral efficacy of TDF monotherapy vs. TDF-LAM combination therapy in 103 patients with LAM-resistant CHB. RESULTS: The study subjects were treated with TDF alone (n=40) or TDF-LAM combination therapy (n=63) for ≥6 months. The patients had previously been treated with TDF-based rescue therapy for a median of 30.0 months (range, 8-36 months). A virologic response (VR) was achieved in 99 patients (96.1%): 95.0% (38/40) of patients in the TDF monotherapy group and 96.8% (61/63) of patients in the TDF-LAM combination therapy group. The VR rates were not significantly different between the TDF monotherapy and TDF-LAM combination therapy groups (88.9 vs. 87.3% at month 12, and 94.4 vs. 93.7% at month 24, log-rank p=0.652). Univariate and multivariate analyses revealed that none of the pretreatment factors were significantly associated with VR. CONCLUSIONS: TDF monotherapy was as effective as TDF-LAM combination therapy for maintaining viral suppression in the vast majority of patients with LAM-resistant CHB, which suggests that TDF add-on therapy with LAM is unnecessary.

Comparison of the clinical outcomes between antiviral-naïve patients treated with entecavir and lamivudine-resistant patients receiving adefovir add-on lamivudine combination treatment

BACKGROUND/AIMS: To analyze the effects of preexisting lamivudine (LAM) resistance and applying antiviral treatment (adefovir [ADV] add-on LAM combination treatment) on long-term treatment outcomes, and comparing the clinical outcomes of antiviral-naïve chronic hepatitis B patients receiving entecavir (ETV) monotherapy. METHODS: This study enrolled 73 antiviral-naïve patients who received 0.5-mg ETV as an initial therapy and 54 patients who received ADV add-on LAM combination treatment as a rescue therapy from July 2006 to July 2010. RESULTS: During 24-month treatments, the decreases in serum log10HBV-DNA values (copies/mL) were significantly greater in the antiviral-naïve patients treated with ETV than the patients receiving ADV add-on LAM combination treatment. The biochemical response rates for alanine aminotransferase normalization at 6 months (ETV) and 12 months (ADV add-on LAM) were 90.4% (66/73) and 77.8% (42/54), respectively (P=0.048). A Kaplan-Meier analysis indicated that the rates of serologic response, viral breakthrough, and emergence of genotypic resistance did not differ significantly between the two patient groups. There were also no significant intergroup differences in the rates of disease progression (PD) and new development of hepatocellular carcinoma (HCC). CONCLUSION: The long-term clinical outcomes of antiviral-naïve patients treated with ETV and LAM-resistant patients receiving ADV add-on LAM combination treatment were comparable in terms of the emergence of HCC and disease progression.

Efficacy and Safety of Tenofovir-Based Rescue Therapy for Chronic Hepatitis B Patients with Previous Nucleo(s/t)ide Treatment Failure

BACKGROUND/AIMS: We investigated the efficacy and safety of tenofovir disoproxil fumarate (TDF)-based treatment in chronic hepatitis B (CHB) patients who failed previous antiviral therapies. METHODS: Seventeen patients who failed to achieve virological responses during sequential antiviral treatments were included. The patients were treated with TDF monotherapy (four patients) or a combination of TDF and lamivudine (13 patients) for a median of 42 months. Hepatitis B virus (HBV) DNA and hepatitis B e antigen (HBeAg) were measured, and renal function was also monitored. RESULTS: Prior to TDF therapy, 180 M, 204 I/V/S, 181 T/V, 236 T, and 184 L mutations were detected. After TDF therapy, the median HBV DNA level decreased from 4.6 log10 IU/mL to 2.0 log10 IU/mL and to 1.6 log10 IU/mL at 12 and 24 months, respectively. HBV DNA became undetectable (< or =20 IU/mL) in 14.3%, 41.7%, and 100% of patients after 12, 24, and 48 months of treatment, respectively. HBeAg loss was observed in two patients. Viral breakthrough occurred in five patients who had skipped their medication. No significant changes in renal function were observed. CONCLUSIONS: TDF-based rescue treatment is effective in reducing HBV DNA levels and is safe for patients with CHB who failed prior antiviral treatments. Patients' adherence to medication is related to viral rebound.

Options for the management of antiviral resistance during hepatitis B therapy: reflections on battles over a decade

Although much advancement has been achieved in the treatment of chronic hepatitis B, antiviral resistance is still a challenging issue. Previous generation antiviral agents have already developed resistance in a number of patients, and it is still being used especially in resource limited countries. Once antiviral resistance occurs, it predisposes to subsequent resistance, resulting in multidrug resistance. Therefore, prevention of initial antiviral resistance is the most important strategy, and appropriate choice and modification of therapy would be the cornerstone in avoiding treatment failures. Until now, management of antiviral resistance has been evolving from sequential therapy to combination therapy. In the era of tenofovir, the paradigm shifts again, and we have to decide when to switch and when to combine on the basis of newly emerging clinical data. We expect future eradication of chronic hepatitis B virus infection by proper prevention and optimal management of antiviral resistance.

Surveillance programs for detection and characterization of emergent pathogens and antimicrobial resistance: results from the Division of Infectious Diseases, UNIFESP

Several epidemiological changes have occurred in the pattern of nosocomial and community acquired infectious diseases during the past 25 years. Social and demographic changes possibly related to this phenomenon include a rapid population growth, the increase in urban migration and movement across international borders by tourists and immigrants, alterations in the habitats of animals and arthropods that transmit disease, as well as the raise of patients with impaired host defense abilities. Continuous surveillance programs of emergent pathogens and antimicrobial resistance are warranted for detecting in real time new pathogens, as well as to characterize molecular mechanisms of resistance. In order to become more effective, surveillance programs of emergent pathogens should be organized as a multicenter laboratory network connected to the main public and private infection control centers. Microbiological data should be integrated to guide therapy, adapting therapy to local ecology and resistance patterns. This paper presents an overview of data generated by the Division of Infectious Diseases, Federal University of São Paulo, along with its participation in different surveillance programs of nosocomial and community acquired infectious diseases.

Várias alterações epidemiológicas ocorreram no perfil das doenças infecciosas hospitalares e comunitárias nos últimos 25 anos. Mudanças sociais e demográficas possivelmente relacionadas com esse fenômeno incluem o rápido crescimento populacional, o aumento da migração urbana e deslocamento através de fronteiras internacionais por turistas e imigrantes, alterações nos habitats de animais e artrópodes que transmitem doença assim como o aumento no número de pacientes com deficiências nas respostas de defesa. Os programas contínuos de vigilância de patógenos emergentes e resistência antimicrobiana são necessários para a detecção em tempo real de novos patógenos assim como para caracterizar mecanismos moleculares de resistência. Para serem mais efetivos, os programasde vigilância dos patógenos emergentes devem ser organizados em uma rede de laboratórios multicêntricos ligados aos principais centros de controle de infecções, públicos e privados. Os dados microbiológicos devem ser integrados a guias terapêuticos adaptando práticas terapêuticas à ecologia local eaos padrões de resistência. O artigo apresenta uma revisão dos dados gerados pela Disciplina de Infectologia, Universidade Federal de São Paulo, contemplando sua participação nos diferentes programas de vigilância de doenças infecciosas hospitalares e adquiridas na comunidade.

Comparison of interferon monotherapy with interferon-lamivudine combination treatment in children with chronic hepatitis B.

AIM: To compare interferon monotherapy with combination treatment using interferon and lamivudine in children with chronic hepatitis B. METHODS: Data from 65 children who had received either interferon-alpha (5 MU/m2 subcutaneous thrice a week for 6 months; n=35; Group 1) or this dose of interferon-alpha for 6 months with oral lamivudine for one year (4 mg/Kg/day, maximum 100 mg/day; n=30; Group 2) were analyzed retrospectively. Complete response was defined as ALT normalization, HBeAg/anti-HBe seroconversion and HBV DNA clearance. RESULTS: ALT normalization rates were similar in Groups 1 and 2 at the end of interferon treatment (13 [38%] and 16 [52%], respectively), at 12 months (19 [56%] and 18 [58%]) and at 24 months (24 [71%] and 23 [74%]). HBV DNA clearance was more frequently observed at 6 months in Group 2 than in Group 1 (19 [63%] versus 7 [20%]; p=0.01), but not at 12 months (19 [63%] versus 17 [49%]) or at 24 months (20 [67%] versus 21 [60%]). Rate of HBeAg/anti-HBe seroconversion was higher in Group 2 at 12 months (18 [60%] versus 11 [31%]; p< 0.05). Rate of complete response was similar in Groups 1 and 2 at 6 months (5 [14%] and 10 [33%], respectively), 12 months (14 [40%] and 17 [57%]) and 24 months (20 [57%] and 19 [63%]). CONCLUSION: Although lamivudine and interferon combination achieved higher initial rates of HBV DNA loss and HBeAg/anti-HBe seroconversion than interferon alone, the final response rates were similar with the two treatments. The combination treatment is therefore not indicated for chronic hepatitis B in children.

Adefovir Dipivoxil Alone or in Combination with Ongoing Lamivudine in Patients with Decompensated Liver Disease and Lamivudine-resistant Hepatitis B Virus

The purpose of this prospective study was to evaluate the efficacy and safety of adefovir dipivoxil with or without ongoing lamivudine in decompensated lamivudine-resistant chronic hepatitis B patients. Forty-six hepatitis B e antigen (HBeAg)-positive patients with decompensated liver function and lamivudine-resistant hepatitis B virus (HBV) were assigned to adefovir dipivoxil monotherapy (n=18) or combination therapy with ongoing lamivudine (n=28) according to their own preference. After 24 weeks of treatment, 83% of monotherapy and 86% of combination therapy showed serum HBV DNA below detection limit (<0.5 pg/mL). Alanine aminotransferase (ALT) normalized in 78% and 82% respectively. Median Child-Pugh-Turcotte (CPT) score or Model for End-Stage Liver Disease (MELD) score reduced significantly by 3 or 5 point in monotherapy and 2 or 2 point in combination therapy respectively. There were no significant differences in rate of undetectable serum HBV DNA, median change of ALT and median reduction of CPT or MELD scores between the two groups. In conclusion, both adefovir dipivoxil monotherapy and combination therapy with ongoing lamivudine result in comparable virologic, biochemical, and clinical improvements in HBeAg-positive patients with decompensated liver function and lamivudine-resistant HBV. Combination with lamivudine showed no additional benefit over monotherapy during 24 weeks of treatment in these patients.