Long-term efficacy of entecavir plus adefovir combination therapy versus entecavir monotherapy in adefovir refractory chronic hepatitis B patients with prior lamivudine resistance

Cost-Effectiveness Comparison Between the Response-Guided Therapies and Monotherapies of Nucleos(t)ide Analogues for Chronic Hepatitis B Patients in China

BACKGROUND AND OBJECTIVE

Nucleos(t)ide analogue (NA) monotherapies are typically used as the primary treatment for chronic hepatitis B (CHB) patients, including lamivudine (LAM), telbivudine (TBV), adefovir (ADV), entecavir (ETV) and tenofovir (TDF). For high-resistance NAs (LAM, TBV, ADV), they can generate excellent clinical outcomes by using response-guided therapy; however, their pharmacoeconomic profiles remain unclear in China. We aimed to evaluate the cost effectiveness between response-guided therapies and monotherapies of NAs for Chinese hepatitis B e-antigen (HBeAg)-positive and -negative CHB patients.

METHODS

We constructed a Markov model to simulate CHB progression associated with 12 treatment strategies using effectiveness and cost data from the published literature. We measured the lifetime costs, quality adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs). One-way sensitivity (especially to extend the range of the TDF price) and probabilistic sensitivity analyses were used to explore the uncertainties of the model.

RESULTS

For both HBeAg-positive and -negative patients, no treatment strategy generated the lowest lifetime costs (US$31,185-US$31,338) and QALYs (7.54-7.58). ETV and TDF monotherapies were not dominated by other treatments, whereas, the ICER of ETV monotherapy was the lowest (US$6112/QALY-US$8533/QALY). For each high-resistance NA, compared with its monotherapy, the ICERs of its response-guided therapies were below the willingness-to-pay threshold of US$22,833/QALY. Additionally, TDF monotherapy was the preferred treatment when its price dropped to US$1820/year or lower.

CONCLUSION

Among 12 treatment strategies evaluated, ETV monotherapy is the most cost-effective treatment for treatment-naive CHB patients in China. The response-guided therapies of high-resistance NAs are more cost-effective than their monotherapies.

The Efficacy of Add-on Telbivudine Versus Switching to Pegylated Interferon Alfa-2a in Chronic Hepatitis B Patients With Poor Responses to Adefovir

BACKGROUND

There are limited options for chronic hepatitis B (CHB) patients who have poor responses to adefovir (ADV).

OBJECTIVES

The aim of this study is to evaluate the effects of adding on telbivudine (LdT) or switching to pegylated interferon alfa-2a (PEG-IFN-α2a) as alternative rescue therapies for patients with poor responses to the initial ADV treatments.

PATIENTS AND METHODS

Ninety-seven CHB patients with HBV DNA > 2 log10 copies/mL 48 weeks after ADV monotherapy were included in this study. Fifty-nine of these patients were treated with a combination of LdT plus ADV (LdT + ADV) daily, while thirty-eight patients were switched to PEG-IFN-α2a subcutaneous injections weekly for 48 weeks.

RESULTS

Both rescue strategies were proven to be safe and the majority of patients tolerated the therapies well. LdT + ADV led to more rapid reductions in viral loads than PEG-IFN-α2a monotherapy, with 2.14 (LdT + ADV) and 0.98 (PEG-IFN-α2a) log10 copies/mL decreases 48 weeks after rescue treatments, respectively (P < 0.00001). The rates corresponding to virological and biochemical responses were also elevated in patients who received the LdT + ADV combination therapy at the end of the observation period (88.1 vs. 68.4% for virological response, P = 0.017; 83.3 vs. 47.2%, P = 0.00045). However, the decline in the hepatitis B surface antigen (HBsAg) was more pronounced in PEG-IFN-α2a treated patients. Moreover, the cumulative rates of serological responses were higher in patients who switched to the PEG-IFN-α2a therapy.

CONCLUSIONS

Both add-on LdT and switching to PEG-IFN-α2a were satisfactory and optimal treatments for CHB patients with poor responses to ADV. Both rescue strategies resulted in significant reductions in serum viral load and ALT levels, and were associated with high rate of serological outcomes in our hospital.

Molecular Mechanisms to Control Post-Transplantation Hepatitis B Recurrence

Hepatitis B often progresses to decompensated liver cirrhosis requiring orthotopic liver transplantation (OLT). Although newer nucleos(t)ide analogues result in >90% viral and hepatitis activity control, severely decompensated patients still need OLT because of drug-resistant virus, acute exacerbation, or hepatocellular carcinoma. Acute hepatitis B is also an indication for OLT, because it can progress to fatal acute liver failure. After OLT, the hepatitis B recurrence rate is >80% without prevention, while >90% of transplant recipients are clinically controlled with combined hepatitis B immunoglobulin (HBIG) and nucleos(t)ide analogue treatment. However, long-term HBIG administration is associated with several unresolved issues, including limited availability and extremely high cost; therefore, several treatment protocols with low-dose HBIG, combined with nucleos(t)ide analogues, have been investigated. Another approach is to induce self-producing anti-hepatitis B virus (HBV) antibodies using an HBV envelope (HBs) antigen vaccine. Patients who are not HBV carriers, such as those with acutely infected liver failure, are good candidates for vaccination. For chronic HBV carrier liver cirrhosis patients, a successful vaccine response can only be achieved in selected patients, such as those treated with experimentally reduced immunosuppression protocols. The present protocol for post-OLT HBV control and the future prospects of newer treatment strategies are reviewed.

Telbivudine protects renal function in patients with chronic hepatitis B infection in conjunction with adefovir-based combination therapy

Previous studies have demonstrated that the treatment of chronic hepatitis B (CHB) infection with adefovir (ADV) can impair renal function. In contrast, treatment with telbivudine (LdT) improves renal function in CHB patients. The aim of this study was to evaluate the renoprotective effect of LdT in CHB patients receiving ADV-based combination therapy. The effects of treatment with ADV + LdT on renal function were compared to those resulting from treatment with ADV + entecavir (ETV), ADV + lamivudine (LAM), ADV alone and ETV alone. The consecutive cohort analysis included 831 CHB patients who received ADV + LdT, ADV + LAM, ADV + ETV, ADV alone or ETV alone for 96 weeks. Alterations in estimated glomerular filtration rate (eGFR) were compared between the five groups using a linear mixed-effects model. HBV DNA levels were also compared between the five groups during the 96-week period. Among the five treatment groups, significant improvements in eGFR were observed in the ADV + LdT and ADV + LAM groups over time (P < 0.001 for each group compared with baseline eGFR). In patients with a baseline eGFR between 50 and 90 mL/min, the change in eGFR was the most significant in the ADV + LdT group (+0.641 mL/min; P < 0.001). Age, gender, baseline eGFR and treatment option were significant predictive factors for eGFR changes. In conclusion, our results suggest that the combination therapy of LdT and ADV is significantly associated with renoprotective effects in CHB patients when compared with other ADV-based combination or single therapies.

Comparison of lamivudine plus adefovir therapy versus entecavir with or without adefovir therapy for adefovir-resistant chronic hepatitis B

BACKGROUND AND GOALS

Data regarding the management of adefovir (ADV) resistance are still limited. The aim of this study is to investigate treatment outcomes of rescue therapy in ADV-resistant chronic hepatitis B (CHB) patients.

STUDY

CHB patients who began rescue therapy due to documented genotypic resistance mutations to ADV between October 2006 and July 2012 were retrospectively reviewed.

RESULTS

Sixty-three patients were included in this study. Most patients had history of lamivudine (LAM) resistance. Treatment response was evaluated at 3-month intervals up to 12 months. The cumulative rate of complete virologic response (CVR) in hepatitis B virus (HBV)-infected patients (HBV DNA<60 IU/mL) was 15.9%, 27.2%, 28.9%, and 31.7% after 3, 6, 9, and 12 months of rescue therapy. Thirty-five patients were treated with a combination of LAM plus ADV (LAM+ADV group) and 28 patients were treated with entecavir (ETV)-based therapy (ETV with or without ADV therapy, ETV±ADV group). The cumulative CVR rate was significantly higher in the ETV±ADV group than in the LAM+ADV group at month 12 (46.4% vs. 20.6%, respectively, P=0.040). Multivariate analysis showed that pretreatment serum HBV DNA levels at <6 log10 IU/mL (hazard ratio: 34.109, P=0.001) and type of rescue therapy (hazard ratio: 4.944, P=0.036) were associated with CVR.

CONCLUSIONS

Lower baseline HBV DNA level and ETV±ADV therapy were the important predictive factors for CVR in ADV-resistant CHB patients. This study suggests the need of early switching to a rescue therapy such as ETV±ADV at the time of low-level viremia.

Management of antiviral drug resistance in chronic hepatitis B

Rescue antiviral treatment for patients with resistance to preexisting nucleos(t)ide analogues remains a clinical challenge. The correct choice of a first-line treatment of high potency and with a high genetic barrier to achieve sustained long-term suppression of viral replication provides the best chance of preventing treatment failure and the emergence of drug resistance. The management of treatment failure and drug resistance requires a precise and accurate clinical and virologic monitoring. Combination treatment with antiviral drugs that belong to different groups is associated with a lower chance of developing resistance to rescue drugs. To guarantee better control of viral replication in patients with drug resistance, the addition of another drug without a cross resistance profile should be given as early as possible, preferably at the time when genotypic resistance emerges. Long-term surveillance for treatment efficacy and possible emergence of drug resistance should be continued to prevent the emergence of multidrug-resistant strains.