Reducción en la infección por VHB y VHD en dos poblaciones indígenas de la Amazonia peruana después de la vacunación contra la hepatitis B / Reduction of HBV and HDV infection in two indigenous peoples of Peruvian Amazon after the vaccination against hepatitis B

Resumen: Objetivo: Conocer el resultado de la vacunación contra la hepatitis B en las comunidades hiperendémicas Kandozi y Chapra de la Amazonia Peruana a partir de la prevalencia de infecciones por los virus de la hepatitis B (VHB) y Delta (VHD), ocho años después de iniciada la vacunación. Material y métodos: Se realizó un estudio transversal en 2 944 pobladores de 67 comunidades indígenas Kandozi y Chapra en abril de 2010. El tamizaje serológico para el antígeno de superficie del VHB (HBsAg), anticuerpos anti-HBc IgM e IgG, anticuerpos anti-HBs y anti-VHD se determinaron mediante pruebas de ELISA. Resultados: Las tasas de prevalencia del HBsAg, anti-HBc IgG, anti-HBs ≥10 mlUI/ml y anti-VHD fueron 2.3, 39.13, 50.95 y 2.11%, respectivamente. La prevalencia del HBsAg en niños <11 años fue cero. Entre los portadores del HBsAg, las tasas de prevalencia de sobreinfeccion por el VHD e infección aguda por el VHB fueron 2.11% (todos fueron >14 años) y 11.94%, respectivamente. Conclusiones: Estos hallazgos muestran la eliminación de portadores de VHB en niños <11 años, ocho años después de iniciada la vacunación contra el VHB.

Abstract: Objective: To determine the outcome of the vaccination against hepatitis, we determined the prevalence of hepatitis B virus (HBV) and hepatitis D virus (HDV) infections, eight years after introduction of the vaccination. Materials and methods: A cross-sectional study was performed in 2 944 participants of 67 Kandozi and Chapra indigenous peoples in April 2010. Serological screening for hepatitis B surface antigen (HBsAg), antibody anti-HBc IgM and IgG, antibody anti-HBs and anti-HDV were determined by ELISA tests. Results: The prevalence rates of HBsAg, anti-HBc total, anti-HBs ≥10 mlUI/ml and anti-HDV were 2.3, 39.13, 50.95 and 2.11%, respectively. The prevalence rate of HBsAg in children <11 years was 0%. Among carriers of HBsAg, the prevalence rates of HDV and acute HBV infections were 2.11% (all were >14 years) and 11.94%, respectively. HBsAg and anti-HBc total were associated with individuals ≥10 years (p<0.001). Conclusions: These findings show the elimination of HBV carriers in children <11 years, eight years following introduction of the vaccination against HBV.

The expert consensus on clinical cure (functional cure) of chronic hepatitis B / 中华肝脏病杂志

Chronic hepatitis B virus (HBV) infection remains a major world public health problem. Current guidelines for the prevention and treatment of chronic hepatitis B (CHB) have suggested clinical cure (also known as functional cure) as the ideal therapeutic goal, which is associated with decreased risk of cirrhosis and hepatocellular carcinoma. Clinical cure is defined as sustained, undetectable serum HBsAg, HBeAg and HBV DNA with or without seroconversion to anti-HBs, but with the persistence of residual cccDNA, accompanied by resolution of liver injury after the completion of a finite course of treatment. Accumulating data from a series of randomized controlled trials as well as clinical practice have confirmed certain clinical benefit of optimal sequential/ combination strategies of direct acting antiviral drugs (DAA) [such as nucleoside analogues (NA)] or immunomodulators (such as pegylated interferon alpha (Peg-IFN)] for appropriately selected CHB patients. This consensus provides an updated and comprehensive analysis of the data supporting the use of combination therapies and summarizes the roadmap towards clinical cure of CHB to guide decision-making in clinical practice.

Identification of hepatitis B virus A1762T/G1764A double mutant strain in patients in Southern Brazil

Abstract Infection by hepatitis B virus (HBV) is a worldwide public health problem. Chronic HBV infection with high viral replication may lead to cirrhosis and/or hepatocellular carcinoma. Mutant HBV strains, such as the HBV A1762T/G1764A double mutant, have been associated with poor prognosis and higher risk of the patient for developing cirrhosis and/or hepatocellular carcinoma. This study analyzed the presence of the HBV A1762T/G1764A double mutant in patients with chronic HBV and its association with clinical parameters such as viral load, aminotransferases, and HBV antigens. A total of 49 patients with chronic hepatitis B were included in the study, and the HBV A1762T/G1764A double mutant strain was detected in four samples (8.16%) by polymerase chain reaction followed by restriction fragment length analysis (PCR-RFLP). The viral load was not significantly different between patients with or without the double mutant strain (p = 0.43). On the other hand, carriers of the HBV A1762T/G1764A double mutant had higher levels of ALT (p = 0.0028), while AST levels did not differ between groups (p = 0.051). In this study, 75% of the samples with the HBV A1762T/G1764A double mutation were HBeAg negative and anti-HBe positive, reflecting seroconversion even though they still displayed high viral loads. Our study has shown that the HBV A1762T/G1764A double mutant strain circulates in Brazilian patients, and is associated with elevated levels of ALT and HBeAg seroconversion.

Predictors of HBeAg seroconversion after long-term nucleos(t)ide analogues treatment for chronic hepatitis B: a multicenter study in real clinical setting

ABSTRACT Aims: To evaluate the HBeAg seroconversion rate in real clinical setting and explore its predictors in long-term nucleos(t)ide analogues (NAs) treatment for chronic hepatitis B (CHB). Methods: 251 patients were recruited from January 2001 to September 2009 in four hospitals in Hebei province, China, for this retrospective study. Clinical and laboratory data before and after treatment with lamivudine (LAM, 100 mg daily), adefovir (ADV, 10 mg daily), telbivudine (LDT, 600 mg daily), entecavir (ETV, 0.5 mg daily), and LAM/ADV combination were compared among three groups according to treatment outcomes: synchronous HBeAg loss and HBeAg seroconversion, anti-HBe development after treatment, and no anti-HBe. Adherence was also evaluated. Results: In real clinical setting, cumulative HBeAg seroconversion rates were 14.3%, 32.7%, 43.0%, 46.9%, and 50.5% after 1, 2, 3, 5, and 8 years, respectively. 45 patients (17.9%) were non-adherent. Adherence (p < 0.001, Hazard Ratio (HR) = 2.203), elevated alanine aminotransferase (ALT) levels (p < 0.001, HR = 2.049), and non-vertical transmission (p = 0.006, HR = 1.656) were predictors of HBeAg seroconversion. Conclusion: Adherence, elevated ALT, and non-vertical transmission are predictors of HBeAg seroconversion in CHB patients treated with NAs.

Cost-Effectiveness and Clinical Impact of Antiviral Strategies of HBeAG-Positive and Negative Chronic Hepatitis B

ABSTRACT Introduction. Chronic hepatitis B (CHB) is associated with high burden and healthcare costs. Virologic response achieved with antivirals is associated with progression avoidance. This study aimed to estimate the efficiency and clinical impact of antiviral strategies in CHB patients. Material and methods. A Markov model estimated lifetime complications and direct costs in both, HBeAg-positive and HBeAg-negative cohorts. Strategy 1 (71% of treated population) and strategy 2 (100%), both based on pegylated interferon (peg-IFN) followed by oral tenofovir or entecavir, were compared to no treatment. Progression was based on HBV-DNA levels. Rescue therapy with oral antivirals was applied for peg-IFN failure. Disease costs (€, 2014) and utilities were obtained from literature. Results. Compared to natural history, strategy 1 increased QALY (3.98 in HBeAg-positive, 2.16 in -negative cohort). With strategy 2, survival was up to 5.60 (HBeAg-positive) and 3.05 QALY (in HBeAg-negative). The model predicted avoidance of 128 and 86 carcinomas in HBeAg-positive and -negative patients with strategy 1, and up to 181 and 121 in HBeAg-positive and -negative for strategy 2. Total cost increased up to €102,841 (strategy 1) and €105,408 (strategy 2) in HBeAg-positive, and €85,858 and €93,754 in HBeAg-negative. A€1,581/QALY gained ratio was estimated versus the natural history for both strategies. In conclusion, increasing antiviral coverage would be efficient, reducing complications.

Poor sensitivity of rapid tests for the detection of antibodies to the hepatitis B virus: implications for field studies

Rapid tests (RTs) can be used as an alternative method for the conventional diagnosis of hepatitis B virus (HBV). This study aims to evaluate antibodies to HBsAg (anti-HBs) and antibodies to HBeAg (anti-HBe) RTs under different Brazilian settings. The following three groups were included: GI: viral hepatitis outpatient services; GII: low resource areas; and GIII: crack users and beauticians. Imuno-rápido anti-HBsAg™ and Imuno-rápido anti-HBeAg™ RTs were evaluated and showed specificities greater than 95% in all groups. The sensitivity values to anti-HBs were 50.38%, 51.05% and 46.73% and the sensitivity values to anti-HBe were 76.99%, 10.34% and 11.76% in the GI, GII and GIII groups, respectively. The assays had a low sensitivity and high specificity, which indicated their use for screening in regions endemic for HBV.

Evolution of hepatitis B serological markers in HIV coinfected patients: a case study

ABSTRACT OBJECTIVE To describe the evolution of serological markers among HIV and hepatitis B coinfected patients, with emphasis on evaluating the reactivation or seroreversion of these markers. METHODS The study population consisted of patients met in an AIDS Outpatient Clinic in São Paulo State, Brazil. We included in the analysis all HIV-infected and who underwent at least two positive hepatitis B surface antigen serological testing during clinical follow up, with tests taken six months apart. Patients were tested with commercial kits available for hepatitis B serological markers by microparticle enzyme immunoassay. Clinical variables were collected: age, sex, CD4+ T-cell count, HIV viral load, alanine aminotransferase level, exposure to antiretroviral drugs including lamivudine and/or tenofovir. RESULTS Among 2,242 HIV positive patients, we identified 105 (4.7%) patients with chronic hepatitis B. Follow up time for these patients varied from six months to 20.5 years. All patients underwent antiretroviral therapy during follow-up. Among patients with chronic hepatitis B, 58% were hepatitis B “e” antigen positive at the first assessment. Clearance of hepatitis B surface antigen occurred in 15% (16/105) of patients with chronic hepatitis B, and 50% (8/16) of these patients presented subsequent reactivation or seroreversion of hepatitis B surface antigen. Among hepatitis B “e” antigen positive patients, 57% (35/61) presented clearance of this serologic marker. During clinical follow up, 28.5% (10/35) of those who initially cleared hepatitis B “e” antigen presented seroreversion or reactivation of this marker. CONCLUSIONS Among HIV coinfected patients under antiretroviral therapy, changes of HBV serological markers were frequently observed. These results suggest that frequent monitoring of these serum markers should be recommended.

TeleCondutas: hepatite B / TeleGuides: Hepatitis B

As hepatite virais apresentam forma clínicas diversas, desde infecções assintomáticas até quadros de hepatopatia avançada, como cirrose e hepatocarcinoma. A equipe da atenção primária deve investigar pessoas com sinais e sintomas comuns da infecção, bem como assintomáticos que fazem parte do grupo de risco. Esta guia apresenta informação que orienta a conduta para casos de hepatite B no contexto da Atenção Primária à Saúde, incluindo: forma de transmissão, quadro clínico, suspeita ou diagnóstico de cirrose, diagnóstico de hepatite b, avaliação sorológica da hepatite b, avaliação de paciente com hepatite b aguda, avaliação de paciente com hepatite b crônica, rastreamento, vacina para hepatite b, encaminhamento para serviço especializado.

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.

New perspectives of biomarkers for the management of chronic hepatitis B

With recent advances in molecular and genomic investigations, the impact of hepatitis B viral and host factors on the progression of chronic HBV infection has been explored. For viral factors, hepatitis B viral load is a strong predictor for liver disease progression. Hepatitis B viral kinetics appear to be important for successful anti-viral therapy. Serum HBsAg level serves as a complementary marker to viral load for the prediction of HBV-related adverse outcomes in patients with low viral load. In those with low viral load, high serum HBsAg level is associated with higher risks of cirrhosis and HCC. Hepatitis B core-related antigen (HBcrAg) induces host immune responses, and the reduction of the HBcrAg level as well as the increment of total anti-HBc level are significantly associated with favorable outcomes. HBV genotypes (genotype C/D) and mutants (basal core promoter and deletion mutation in pre-S genes) are well known viral genetic markers to predict disease progression. For host factors, serum inflammatory biomarkers have been developed to evaluate the HBV-associated hepatic necroinflammation and fibrosis. Host single nucleotide polymorphism on sodium taurocholate cotransporting polypeptide (NTCP, an HBV entry receptor) may be associated with a decreased risk for cirrhosis and HCC. In conclusion, patients with chronic hepatitis B should be evaluated with relevant viral and host markers to identify those who are at a higher risk of liver disease progression and then receive timely antiviral therapy.

Efficacy of switching from adefovir to tenofovir in chronic hepatitis B patients who exhibit suboptimal responses to adefovir-based combination rescue therapy due to resistance to nucleoside analogues (SATIS study)

BACKGROUND/AIMS: It remains to be determined whether switching from adefovir (ADV) to tenofovir (TDF) provides better virological outcomes in patients exhibiting suboptimal responses to ADV plus nucleoside analogue (ADV+NA) therapy for NA-resistant chronic hepatitis B (CHB). METHODS: In this prospective trial, patients who showed partial responses (defined as serum hepatitis B virus [HBV] DNA >60 IU/mL) to ADV+NA therapy for NA resistance were randomly allocated to receive TDF plus NA (TDF+NA group, n=16) or to continue their current therapy (ADV+NA group, n=16). The primary end point was the proportion of patients with complete virological response (CVR, defined as serum HBV DNA 2log10 IU/mL was more likely in the TDF+NA group at both 24 and 48 weeks (68.8% vs. 56.3%, P=0.014 vs. 81.3% vs. 56.3%, P=0.001, respectively). During the follow-up, the rate of HBeAg seroconversion was higher in the TDF+NA group than the ADV+NA group (12.5% vs. 6.25%, P=0.640), as was that for the hepatitis B surface antigen (6.25% vs. 0%, P=0.080). No serious adverse events due to antiviral agents occurred. CONCLUSIONS: In patients exhibiting suboptimal responses to ADV+NA therapy for NA-resistant CHB, switching from ADV to TDF might provide better virological outcomes.

Predictive Factors for Sustained Remission after Discontinuation of Antiviral Therapy in Patients with HBeAg-positive Chronic Hepatitis B / 대한소화기학회지

BACKGROUND/AIMS: The optimal timing for discontinuing oral antiviral therapy in patients with HBeAg-positive chronic hepatitis B (CHB) is unclear. The aim of our study was to investigate sustained remission after stopping antiviral therapy in patients with HBeAg-positive CHB. METHODS: We analyzed the medical records of 58 patients who were HBeAg-positive and had discontinued antiviral therapy. Antiviral therapy was discontinued after HBeAg seroconversion and HBV DNA negativity for 6-12 months with consolidation therapy. Virologic relapse was defined as an increase in serum HBV DNA >2,000 IU/mL. RESULTS: No difference was observed between the virologic non-relapse and virologic relapse groups in baseline HBV DNA level (p=0.441) or duration of seroconversion (p=0.070). Time-to-undetectable HBV DNA during treatment was shorter in the virologic non-relapse group (29 patients) compared to the relapse group (29 patients) (4.9+/-2.6 vs. 13.2+/-12.7 months; p or =18 months, p=0.020) and early virologic response (HBV DNA <20 IU/mL) at six months during antiviral therapy (p=0.017) were significant predictors for sustained remission. CONCLUSIONS: A consolidation period of at least 18 months and early virological response at six months during antiviral therapy were associated with sustained remission in patients with HBeAg-positive CHB after treatment.

Tenofovir disoproxil fumarate monotherapy for nucleos(t)ide analogue-naive and nucleos(t)ide analogue-experienced chronic hepatitis B patients

BACKGROUND/AIMS: This study investigated the antiviral effects of tenofovir disoproxil fumarate (TDF) monotherapy in nucleos(t)ide analogue (NA)-naive and NA-experienced chronic hepatitis B (CHB) patients. METHODS: CHB patients treated with TDF monotherapy (300 mg/day) for > or =12 weeks between December 2012 and July 2014 at a single center were retrospectively enrolled. Clinical, biochemical, and virological parameters were assessed every 12 weeks. RESULTS: In total, 136 patients (median age 49 years, 96 males, 94 HBeAg positive, and 51 with liver cirrhosis) were included. Sixty-two patients were nucleos(t)ide (NA)-naive, and 74 patients had prior NA therapy (NA-exp group), and 31 patients in the NA-exp group had lamivudine (LAM)-resistance (LAM-R group). The baseline serum hepatitis B virus (HBV) DNA level was 4.9+/-2.3 log IU/mL (mean+/-SD), and was higher in the NA-naive group than in the NA-exp and LAM-R groups (5.9+/-2.0 log IU/mL vs 3.9+/-2.0 log IU/mL vs 4.2+/-1.7 log IU/mL, P<0.01). The complete virological response (CVR) rate at week 48 in the NA-naive group (71.4%) did not differ significantly from those in the NA-exp (71.3%) and LAM-R (66.1%) groups. In multivariate analysis, baseline serum HBV DNA was the only predictive factor for a CVR at week 48 (hazard ratio, 0.809; 95% confidence interval, 0.729-0.898), while the CVR rate did not differ with the NA experience. CONCLUSIONS: TDF monotherapy was effective for CHB treatment irrespective of prior NA treatment or LAM resistance. Baseline serum HBV DNA was the independent predictive factor for a CVR.

Long-term efficacy of tenofovir disoproxil fumarate therapy after multiple nucleos(t)ide analogue failure in chronic hepatitis B patients

BACKGROUND/AIMS: The efficacy of tenofovir disoproxil fumarate (TDF) for the treatment of chronic hepatitis B (CHB) patients following prior treatment failure with multiple nucleos(t)ide analogues (NAs) is not well defined, especially in Asian populations. In this study we investigated the efficacy and safety of TDF rescue therapy in CHB patients after multiple NA treatment failure. METHODS: The study retrospectively analyzed 52 CHB patients who experienced failure with two or more NAs and who were switched to regimens containing TDF. The efficacy and safety assessments included hepatitis B virus (HBV) DNA undetectability, hepatitis B envelop antigen (HBeAg) seroclearance, alanine transaminase (ALT) normalization and changes in serum creatinine and phosphorus levels. RESULTS: The mean HBV DNA level at baseline was 5.4 +/- 1.76 log10 IU/mL. At a median duration of 34.5 months of TDF treatment, the cumulative probabilities of achieving complete virological response (CVR) were 25.0%, 51.8%, 74.2%, and 96.7% at 6, 12, 24, and 48 months, respectively. HBeAg seroclearance occurred in seven of 48 patients (14.6%). ALT levels were normalized in 27 of 31 patients (87.1%) with elevated ALT at baseline. Lower levels of HBV DNA at baseline were significantly associated with increased CVR rates (p < 0.001). However, CVR rates did not differ between TDF monotherapy or combination therapy with other NAs, and were not affected by mutations associated with resistance to NAs. No significant adverse events were observed. CONCLUSIONS: TDF is an efficient and safe rescue therapy for CHB patients after treatment failure with multiple NAs.

Efficacy of prolonged entecavir monotherapy in treatment-naive chronic hepatitis B patients exhibiting a partial virologic response to entecavir

BACKGROUND/AIMS: The optimal management of patients exhibiting a partial virologic response (PVR) to entecavir (ETV) has not been determined . The aim of this study was to determine the long-term efficacy of prolonged ETV monotherapy in treatment-naive chronic hepatitis B (CHB) patients exhibiting a PVR to ETV therapy. METHODS: This study included 364 treatment-naive CHB patients treated with ETV for > or =48 weeks and who received continuous ETV monotherapy for > or =96 weeks. PVR was defined as a decrease in serum hepatitis B virus (HBV) DNA of more than 2 log10 IU/mL from baseline but with detectable HBV DNA by real-time PCR assay at week 48. RESULTS: Fifty-two of the 364 patients (14.3%) showed a PVR. Among them, 41 patients received continuous ETV monotherapy for > or =96 weeks (median duration 144 weeks, range 96-312 weeks), and 40 of these patients (95%) achieved a virologic response (VR, HBV DNA <20 IU/mL) during prolonged ETV monotherapy (median duration 78 weeks, range 60-288 weeks). The cumulative probabilities of a VR at weeks 96, 144, and 192 from treatment initiation were 78.0%, 92.7%, and 95.1%, respectively. The VR rate was 97.2% (35/36) in HBeAg-positive patients and 100% (5/5) in HBeAg-negative patients. In multivariate analysis, HBeAg positivity (odds ratio [OR], 9.231; 95% confidence interval [CI], 1.03-82.91; P=0.047) and a high baseline HBV DNA level (OR, 0.170; 95% CI, 0.08-0.37; P=0.000) were independently associated with a delayed virologic response. No patient developed genotypic resistance to ETV during follow-up. CONCLUSIONS: Long-term ETV monotherapy is effective for achieving a VR in treatment-naive CHB patients exhibiting a PVR to ETV. HBeAg positivity and high baseline HBV DNA level were independently associated with a delayed virologic response.

The factors associated with longitudinal changes in liver stiffness in patients with chronic hepatitis B

BACKGROUND/AIMS: Liver stiffness (LS) as assessed by transient elastography (TE) can change longitudinally in patients with chronic hepatitis B (CHB). The aim of this study was to identify the factors that improve LS. METHODS: Between April 2007 and December 2012, 151 patients with CHB who underwent two TE procedures with an interval of about 2 years were enrolled. Ninety-six of the 151 patients were treated with nucleos(t)ide analogues [the antiviral therapy (+) group], while the remaining 55 patients were not [the antiviral therapy (-) group]. The two groups of patients were stratified according to whether they exhibited an improvement or a deterioration in LS during the study period (defined as an LS change of 0 kPa, respectively, over a 1-year period), and their data were compared. RESULTS: No differences were observed between the antiviral therapy (+) and (-) groups with respect to either their clinical characteristics or their initial LS. The observed LS improvement was significantly greater in the antiviral therapy (+) group than in the antiviral therapy (-) group (-3.0 vs. 0.98 kPa, P=0.011). In the antiviral therapy (+) group, the initial LS was higher in the LS improvement group (n=63) than in the LS deterioration group (n=33; 7.9 vs. 4.8 kPa, P<0.001). However, there were no differences in any other clinical characteristic. In the antiviral therapy (-) group, the initial LS was also higher in the LS improvement group (n=29) than in the LS deterioration group (n=26; 8.3 vs. 6.5 kPa, P=0.021), with no differences in any other clinical characteristic. CONCLUSIONS: A higher initial LS was the only factor associated with LS improvement in patients with CHB in this study.

Hepatitis B Surface Antigen Quantification across Different Phases of Chronic Hepatitis B Virus Infection Using an Immunoradiometric Assay

BACKGROUND/AIMS: Quantification of hepatitis B surface antigen (HBsAg) is an emerging serologic test and may be useful for identifying treatment strategies for chronic hepatitis B (CHB). This study aimed to evaluate HBsAg titers during the natural course of CHB and identify correlations between HBsAg titers and hepatitis B virus (HBV) DNA concentrations across different CHB phases measured using an immunoradiometric assay (IRMA). METHODS: CHB phases were defined on the basis of HBV DNA concentrations, the presence of hepatitis B e antigen/antibody (HBeAg/Ab) and serum alanine aminotransferase levels. Serum HBsAg titers and paired HBV DNA concentrations in the different phases of CHB were compared using 627 serum samples. RESULTS: Mean HBsAg titers were significantly higher in the immunotolerant (IT) phase and immunoreactive (IR) HBeAg-positive phase than in the low-replicative (LR) and HBeAg-negative CHB (ENH) states. The correlation between HBsAg titers and HBV DNA concentrations was modest in the IT (n=36, r=0.804, p<0.001) and IR (n=48, r=0.773, p<0.001) phases, and it was poor in the LR state (n=116, r=0.289, p=0.002); however, no significant correlation was observed in the ENH state (n=67, r=0.146, p=0.237) or in the oral nucleos(t)ide analogue-treated group (n=267). CONCLUSIONS: HBsAg quantification using IRMA might be useful for discriminating different CHB phases and different stages of chronic liver disease.

Is it necessary to delay antiviral therapy for 3-6 months to anticipate HBeAg seroconversion in patients with HBeAg-positive chronic hepatitis B in endemic areas of HBV genotype C?

BACKGROUND/AIMS: Spontaneous HBeAg seroconversion occurs frequently in the immune reactive phase in HBeAg-positive chronic hepatitis B (CHB). Therefore, observation for 3-6 months before commencing antiviral therapy is recommended in patients with alanine aminotransferase (ALT) levels that exceed twice the upper limit of normal (ULN). However, HBeAg seroconversion occurs infrequently in patients infected with hepatitis B virus (HBV) genotype C. The aim of the present study was to determine whether the waiting policy is necessary in endemic areas of HBV genotype C infection. METHODS: Ninety patients with HBeAg-positive CHB were followed prospectively without administering antiviral therapy for 6 months. Antiviral therapy was initiated promptly at any time if there was any evidence of biochemical (i.e., acute exacerbation of HBV infection or aggravation of jaundice) or symptomatic deterioration. After 6 months of observation, antiviral therapy was initiated according to the patient's ALT and HBV DNA levels. RESULTS: Only one patient (1.1%) achieved spontaneous HBeAg seroconversion. Biochemical and symptomatic deterioration occurred before 6 months in 17 patients (18.9%) and 5 patients, respectively. High ALT and HBV DNA levels were both independent risk factors for biochemical deterioration. Of 15 patients with HBV DNA > or =5.1x107 IU/mL and ALT > or =5xULN, biochemical deterioration occurred in 7 (46.7%), including 1 patient receiving liver transplantation due to liver failure. CONCLUSIONS: Spontaneous HBeAg seroconversion in patients with HBeAg-positive CHB is rare within 6 months. Biochemical deterioration was common and may lead to liver failure. Immediate antiviral therapy should be considered, especially in patients with high ALT and HBV DNA levels in endemic areas of genotype C infection.

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.

Tenofovir disoproxil fumarate monotherapy for nucleos(t)ide-naive chronic hepatitis B patients in Korea: data from the clinical practice setting in a single-center cohort

BACKGROUND/AIMS: This study assessed the antiviral efficacy and safety of tenofovir disoproxil fumarate (TDF) for up to 12 months in Korean treatment-naive chronic hepatitis B (CHB) patients. METHODS: A total of 411 treatment-naive CHB patients who had been treated with TDF for at least 3 months (median 5.6) were consecutively enrolled. Clinical, biochemical, virological parameters and treatment adherence were routinely assessed every 3 months. RESULTS: The median age was 51.3 years, 63.0% of the patients were male, 49.6% were HBeAg (+), and 210 patients had liver cirrhosis. The median baseline HBV DNA was 5.98 (SD 1.68) log10 IU/mL. Among the patients completing week 48, 83.3% had a complete virologic response (CVR, <12 IU/mL by HBV PCR assay), and 88.2% had normalized levels of alanine aminotransferase (ALT). The cumulative probabilities of CVR at 3, 6, 9 and 12 months were 22.8%, 53.1%, 69.3% and 85.0%. During the follow-up period, 9.8% patients achieved HBeAg loss and 7.8% patients achieved HBeAg seroconversion. There was no virological breakthrough after initiating TDF. The most common TDF-related adverse event was gastrointestinal upset, and three patients discontinued TDF therapy. However, no serious life-threatening side effect was noted. CONCLUSIONS: In a clinical practice setting, TDF was safe and highly effective when administered for 12 months to Korean treatment-naive CHB patients.