Randomized trial of lamivudine versus entecavir in entecavir-treated patients with undetectable hepatitis B virus DNA: outcome at 2 Years

Entecavir-based combination therapies for chronic hepatitis B: A meta-analysis

BACKGROUND

Currently, there is no consensus on the efficacy and safety of the entecavir (ETV) monotherapy versus the ETV-based combination therapy for chronic hepatitis B.

METHODS

A comprehensive literature search was performed on the comparison of ETV-based combination therapy and monotherapy for chronical hepatitis B (CHB) patients in the PubMed, Embase, Web of Science, the Cochrane Libraries, and the Chinese BioMedical Literature Database. Both dichotomous and continuous variables were extracted, and pooled outcomes were expressed as odds ratio (OR) or mean difference (MD).

RESULTS

We included randomized clinical trials (RCTs) and cohorts involving Group A: nucleos(t)ide-naive patients (four RCTs, n = 719 patients), Group B: nucleos(t)ide-resistant patients (four cohorts, n = 196 patients), and Group C: entecavir-treated patients with undetectable hepatitis B virus DNA (two RCTs and two cohorts, n = 297). Group A. ETV monotherapy was better for rates of undetectable HBV DNA, while the rates of the HBV DNA levels at the end of treatment, HBeAg Loss, ALT normalization were similar between the two groups [MD, -0.85 (95% CI, -0.173-0.03); OR, 0.92 (95% CI, 0.24-3.56); OR, 1.31 (95% CI, 0.17-9.82)]; Group B. ETV monotherapy was better for rates of undetectable HBV DNA, while the rates of the HBV DNA levels at the end of treatment, HBeAg Loss, ALT normalization were similar; Group C. The ETV-based combination therapy was better for the rate of HBV DNA relapse.

CONCLUSION

Based on the current data, ETV-based combination therapy seemed to be no better than ETV monotherapy. Further studies are needed to verify this conclusion.

Immunization with lentiviral vector‑modified dendritic cells encoding ubiquitinated hepatitis B core antigen promotes Th1 differentiation and antiviral immunity by enhancing p38 MAPK and JNK activation in HBV transgenic mice

Hepatitis B virus (HBV) infection is a global public health problem. T helper (Th)1‑associated cytokines are involved in HBV clearance during acute and persistent infection. In our previous study, it was demonstrated that lentiviral vectors encoding ubiquitinated hepatitis B core antigen (LV‑Ub‑HBcAg) effectively transduced dendritic cells (DCs) to induce maturation, which promoted T cell polarization to Th1 and generated HBcAg‑specific cytotoxic T lymphocytes (CTLs) ex vivo. In the present study, HBV transgenic mice were immunized with LV‑Ub‑HBcAg‑transduced DCs and HBcAg‑specific immune responses were evaluated. Cytokine expression was analyzed by ELISA. T lymphocyte proliferation was detected with a Cell Counting Kit‑8 assay and HBcAg‑specific CTL activity was determined using a lactate dehydrogenase release assay. The expression levels of p38‑mitogen‑activated protein kinase (p38‑MAPK), phosphorylated (p)‑p38MAPK, c‑Jun N‑terminal kinase (JNK) and p‑JNK were detected by western blot analysis. The results demonstrated that LV‑Ub‑HBcAg‑transduced DCs significantly increased the Th1/Th2 cytokine ratio, and effectively reduced the levels of serum hepatitis B surface antigen (HBsAg), HBV DNA, and liver HBsAg and HBcAg. Furthermore, the LV‑Ub‑HBcAg‑transduced DCs upregulated the expression of p‑P38‑MAPK and p‑JNK in T lymphocytes. In conclusion, the present study indicated that LV‑Ub‑HBcAg‑transduced DCs generated predominant Th1 responses and enhanced CTL activity in HBV transgenic mice. Activation of the P38‑MAPK/JNK signaling pathway may be involved in this induction.

Time-varying serum gradient of hepatitis B surface antigen predicts risk of relapses after off-NA therapy

Background

The serum gradient of hepatitis B surface antigen (HBsAg) varies over time after cessation of nucleos(t)ide analog (NA) treatment in patients with chronic hepatitis B (CHB). The association between the time-varying HBsAg serum gradient and risk of relapse has not been elucidated.

Methods

This multicenter cohort study prospectively enrolled CHB patients who discontinued 3 year-NA treatment. Eligible patients were serologically negative for HBeAg and viral DNA at NA cessation. The participants (n = 140) were followed every 3 months through HBsAg quantification. Virological and clinical relapses were defined as viral DNA levels >2000 IU/mL and alanine aminotransferase (ALT) levels >80 U/mL, respectively. The association of time-varying HBsAg levels with relapses was assessed through a time-dependent Cox analysis.

Results

During a median follow-up of 19.9 (interquartile range [IQR], 10.6–25.3) months, virological and clinical relapses occurred in 94 and 49 patients, with a 2-year cumulative incidence of 79.2% (95% confidence interval [CI], 70.9%–86.4%) and 42.9% (95% CI, 34.1%–52.8%), respectively. The serum level of HBsAg was associated with virological (P < 0.001) and clinical (P = 0.01) relapses in a dose–response manner, with adjusted hazard ratios of 2.10 (95% CI, 1.45–3.04) and 2.32 (95% CI, 1.28–4.21). Among the patients (n = 19) whose HBsAg levels ever dropped below 10 IU/mL, only one and three patients subsequently developed clinical and virological relapses.

Conclusion

The serum gradient of HBsAg measured throughout the off-therapy observation is associated with the subsequent occurrence of virological and clinical relapses in CHB patients who discontinue NA treatment.

Entecavir to Telbivudine Switch Therapy in Entecavir-Treated Patients with Undetectable Hepatitis B Viral DNA

PURPOSE

This study examined 2-year outcome of consecutive therapy using entecavir (ETV) followed by telbivudine (LdT) in subjects with undetectable hepatitis B virus (HBV) DNA level and normal alanine aminotransferase level after the initial 6 months of ETV treatment.

MATERIALS AND METHODS

Sixty subjects were randomized to continue with ETV or switch to LdT. Significant difference in baseline characteristics was not found between the two groups. Persistent HBV DNA level of 20-60 IU/mL in three consecutive samples collected three months apart or singly measured HBV DNA level of >60 IU/mL was defined as virological rebound.

RESULTS

During 96 weeks of follow-up, all subjects of the ETV-only group (n=30) resulted in undetectable HBV DNA level. On the other hand, 83.3% (n=25) of the LdT-switched group showed treatment success. Virological rebound time varied from week 24 to 84 after switching to LdT. HBV DNA level was 180 to 2940 IU/mL at rebound time. All subjects with virological rebound (n=5) showed drug-resistant mutation: three had mutation rtM204I, and two had mutation rtM204V. Consecutive treatment using ETV followed by LdT showed virological rebound in 16.7% of subjects during 96 weeks of follow-up. HBV DNA negativity during initial ETV therapy could not be achieved in patients who switched to LdT.

CONCLUSION

Consecutive treatment using ETV followed by lamivudine was ineffective for treating chronic hepatitis B. LdT was found as a more potent antiviral agent than lamivudine. However, this conclusion requires larger-scale, long-term prospective reviews of the treatment effects of ETV-LdT switch therapy.

Telbivudine versus entecavir in patients with undetectable hepatitis B virus DNA: a randomized trial

BACKGROUND

Telbivudine has been suggested to induce hepatitis B surface antigen (HBsAg) decline to the similar degree as pegylated interferon. We aimed to investigate whether telbivudine could further decrease HBsAg titer in patients who maintain undetectable serum hepatitis B virus (HBV) DNA after initial entecavir treatment.

METHODS

In this open-label trial, patients who had serum HBsAg and HBV DNA levels ≥1,000 IU/mL and <60 IU/mL, respectively, following entecavir (0.5 mg/day) treatment for HBeAg-positive chronic hepatitis B were randomized to either switch treatment to telbivudine (600 mg/day, n = 47) or continue entecavir (n = 50) for 48 weeks.

RESULTS

The baseline characteristics were comparable between groups including HBsAg levels (median, 3.41 log₁₀ IU/mL). All patients had undetectable HBV DNA and normal alanine aminotransferase level. At week 48, the mean change in serum HBsAg levels was not significantly different between the telbivudine and entecavir groups (-0.03 log₁₀ IU/mL vs. -0.05 log₁₀ IU/mL; P = 0.57). No patient experienced HBsAg seroclearance or HBsAg decline >0.5 log₁₀ IU/mL. Eleven patients (23.4%) in the telbivudine group, but none in the entecavir group, experienced virologic breakthrough (P < 0.001). Seven patients (14.9%) exhibited genotypic resistance mutations (M204I +/- L180M) during the virologic breakthrough.

CONCLUSION

Sequential therapy with entecavir followed by telbivudine resulted in a high rate of virologic breakthrough and drug-resistance without any beneficial effect on HBsAg decline. These results do not support the use of low genetic barrier drugs as a switch treatment strategy in patients who achieve virologic response with high genetic barrier drugs.

TRIAL REGISTRATION

NCT01595685 (date of trial registration: May 8, 2012).

Potent natural products and herbal medicines for treating liver fibrosis

Liver fibrosis is a wound-healing response to chronic liver injury characterized by progressive inflammation and deposition of extracellular matrix components. The pathological condition of liver fibrosis involves secretion of extracellular matrix proteins and formation of scar tissue. The major regulators involved in hepatic fibrogenesis are the transforming growth factor (TGF)-β1/SMAD and toll-like receptor 4 (TLR4)-initiated myeloid differentiation primary response 88 gene (MyD88)/NF-ĸB cell signaling pathways. This article reviews natural products and herbal medicines that have demonstrated activity against liver fibrosis through different mechanisms of action, including anti-hepatitis B and C virus activity, anti-inflammation, inhibition of cytokine production and nuclear receptor activation, and free radical scavenging.

HBsAg, HBcAg, and combined HBsAg/HBcAg-based therapeutic vaccines in treating chronic hepatitis B virus infection

BACKGROUND

As the host immunity is diminished in patients with chronic hepatitis B (CHB), different approaches have been used to up-regulate their immune responses to produce therapeutic effects. But, cytokines, growth factors and polyclonal immune modulators could not exhibit sufficient therapeutic effects in these patients. Immune therapy with HBV-related antigens (vaccine therapy) has been used in CHB patients. But there is a paucity of information about the design of HBV antigen-based immune therapy in these patients.

DATA SOURCE

Preclinical and clinical studies on immune therapy with HBsAg-based vaccine, HBcAg and combination of HBsAg/HBcAg-based vaccines have been discussed.

RESULTS

HBsAg-based prophylactic vaccine was used as an immune therapeutic agent in CHB patients; however, monotherapy with HBsAg-based immune therapy could not lead to sustained control of HBV replication and/or liver damages. HBsAg-based vaccine was used as a combination therapy with cytokines, growth factors, and antiviral drugs. HBsAg-based vaccine was also used for cell-based therapy. However, satisfactory therapeutic effects of HBsAg-based vaccine could not be documented in CHB patients. In the mean time, evidences have supported that HBcAg-specific immunity is endowed with antiviral and liver protecting capacities in CHB patients. Recent data concentrate on the clinical use of combined HBsAg- and HBcAg-based vaccines in CHB patients.

CONCLUSION

Antigen-based immune therapy with HBV-related antigens may be an alternative method for the treatment of CHB patients but proper designs of antigens, types of adjuvants, dose of vaccinations, and routes of administration need further analyses for the development of an effective regimen of immune therapy against HBV.

Efficacy of lamivudine or entecavir against virological rebound after achieving HBV DNA negativity in chronic hepatitis B patients

Nucleos(t)ide analogues (NAs) lead to viral suppression and undetectable hepatitis B virus (HBV) DNA in some individuals infected with HBV, but the rate of virological rebound has been unknown in such patients. We examined the prevalence of virological rebound of HBV DNA among NA-treated patients with undetectable HBV DNA. We retrospectively analyzed 303 consecutive patients [158 entecavir (ETV)- and 145 lamivudine (LAM)-treated] who achieved HBV DNA negativity, defined as HBV DNA < 3.7 log IU/mL for at least 3 months. They were followed up and their features, including their rates of viral breakthrough, were determined. Viral rebound after HBV DNA negativity was not observed in the ETV-group. Viral rebound after HBV DNA negativity occurred in 38.7% of 62 HBe antigen-positive patients in the LAM-group. On multivariate analysis, age was an independent factor for viral breakthrough among these patients (P = 0.035). Viral rebound after HBV DNA negativity occurred in 29.1% of 79 HBe antigen-negative patients in the LAM-group. Differently from LAM, ETV could inhibit HBV replication once HBV DNA negativity was achieved. In contrast, LAM could not inhibit HBV replication even if HBV negativity was achieved in the early phase. Attention should be paid to these features in clinical practice.

Adherence, persistence, healthcare utilization, and cost benefits of guideline-recommended hepatitis B pharmacotherapy

OBJECTIVE

To compare pharmacotherapy adherence, persistence, and healthcare utilization/costs among US patients with chronic hepatitis B (CHB) initiated on an oral antiviral monotherapy recommended as first-line treatment by current national (US) guidelines vs an oral antiviral not recommended as first-line monotherapy.

RESEARCH DESIGN AND METHODS

In this retrospective cohort study, patients aged 18-64 with medical claims for CHB who initiated an oral antiviral monotherapy for CHB between 07/01/05 and 01/31/10 were identified from a large US commercial health insurance claims database. Patients were continuously enrolled for a 6-month baseline period and ≥90 days follow-up. They were assigned to 'currently recommended first-line therapy' (RT: entecavir or tenofovir) or 'not currently recommended first-line therapy' (NRT: lamivudine, telbivudine, or adefovir) cohorts.

MAIN OUTCOME MEASURES

Multivariate analyses were conducted to compare treatment adherence, persistence, healthcare utilization, and costs for RT vs NRT cohorts.

RESULTS

Baseline characteristics were similar between RT (n=825) and NRT (n=916) cohorts. In multivariate analyses, RT patients were twice as likely as NRT patients to be adherent (OR=2.09; p<0.01) and persistent (mean: RT=361 days, NRT=298 days; p<0.01) and half as likely to have an inpatient stay (OR=0.527; p<0.01). Between the two oral antivirals recommended as first-line treatment, even though pharmacy cost was higher for entecavir, mean total healthcare costs for entecavir and tenofovir were similar ($1214 and $1332 per patient per month, respectively). Similar results were also observed with regard to adherence, persistence, and healthcare use for entecavir and tenofovir.

CONCLUSIONS

A limitation associated with analysis of administrative claims data is that coding errors can be mitigated but are typically not fully eradicated by careful study design. Nevertheless, the current findings clearly indicate the benefits of initiating CHB treatment with an oral antiviral monotherapy recommended as first-line treatment by current guidelines.

Nucleoside/nucleotide analogues in the treatment of chronic hepatitis B

The current available agents for the treatment of chronic hepatitis B (CHB) include immunomodulatory agents, such as interferon-α and pegylated interferon-α, and oral nucleoside/nucleotide analogues (NAs), including lamivudine, adefovir, telbivudine, entecavir and tenofovir. The NAs work mainly by inhibiting hepatitis B virus (HBV) DNA polymerase activity and thus suppress HBV replication. Oral NAs have become the mainstay of CHB treatment, mainly due to their profound viral suppressive effects and also due in part to the ease of single daily dosing and lack of significant side effects. One major drawback of NA therapy is the development of drug resistance mutations with long-term treatment. Lamivudine, the first oral NA approved for CHB patients, is associated with high rates of drug resistance, with resultant virological relapse and biochemical flare. Fortunately, newer and more potent NAs, such as entecavir and tenofovir, have very low resistance rates, with potent and durable viral suppression. This review is aimed at the current developments in NAs for CHB treatment, detailing the mechanisms of antiviral activity of the different agents, the efficacy of viral suppression, the achievement of treatment endpoints, the development of drug resistance and the optimal strategies for using these drugs.