Management of hepatitis C virus infection in the Asia-Pacific region: an update.

The Asia-Pacific region has disparate hepatitis C virus (HCV) epidemiology, with prevalence ranging from 0·1% to 4·7%, and a unique genotype distribution. Genotype 1b dominates in east Asia, whereas in south Asia and southeast Asia genotype 3 dominates, and in Indochina (Vietnam, Cambodia, and Laos), genotype 6 is most common. Often, availability of all-oral direct-acting antivirals (DAAs) is delayed because of differing regulatory requirements. Ideally, for genotype 1 infections, sofosbuvir plus ledipasvir, sofosbuvir plus daclatasvir, or ombitasvir, paritaprevir, and ritonavir plus dasabuvir are suitable. Asunaprevir plus daclatasvir is appropriate for compensated genotype 1b HCV if baseline NS5A mutations are absent. For genotype 3 infections, sofosbuvir plus daclatasvir for 24 weeks or sofosbuvir, daclatasvir, and ribavirin for 12 weeks are the optimal oral therapies, particularly for patients with cirrhosis and those who are treatment experienced, whereas sofosbuvir, pegylated interferon, and ribavirin for 12 weeks is an alternative regimen. For genotype 6, sofosbuvir plus pegylated interferon and ribavirin, sofosbuvir plus ledipasvir, or sofosbuvir plus ribavirin for 12 weeks are all suitable. Pegylated interferon plus ribavirin has been replaced by sofosbuvir plus pegylated interferon and ribavirin, and all-oral therapies where available, but cost and affordability remain a major issue because of the absence of universal health coverage. Few patients have been treated because of multiple barriers to accessing care. HCV in the Asia-Pacific region is challenging because of the disparate epidemiology, poor access to all-oral therapy because of availability, cost, or regulatory licensing. Until these problems are addressed, the burden of disease is likely to remain high.

Boceprevir early-access for advanced-fibrosis/cirrhosis in Asia-Pacific hepatitis C virus genotype 1 non-responders/relapsers.

AIM: To examined the efficacy and safety of treatment with boceprevir, PEGylated-interferon and ribavirin (PR) in hepatitis C virus genotype 1 (HCVGT1) PR treatment-failures in Asia. METHODS: The Boceprevir Named-Patient Program provided boceprevir to HCVGT1 PR treatment-failures. Participating physicians were invited to contribute data from their patients: baseline characteristics, on-treatment responses, sustained virological response at week 12 (SVR12), and safety were collected and analysed. Multivariate analysis was performed to determine predictors of response. RESULTS: 150 patients were enrolled from Australia, Malaysia, Singapore and Thailand (Asians = 86, Caucasians = 63). Overall SVR12 was 61% (Asians = 59.3%, Caucasians = 63.5%). SVR12 was higher in relapsers (78%) compared with non-responders (34%). On-treatment responses predicted SVR, with undetectable HCVRNA at week 4, 8 and 12 leading to SVR12s of 100%, 87%, and 82% respectively, and detectable HCVRNA at week 4, 8 and 12, leading to SVR12s of 58%, 22% and 6% respectively. Asian patients were similar to Caucasian patients with regards to on-treatment responses. Patients with cirrhosis (n = 69) also behaved in the same manner with regards to on-treatment responses. Those with the IL28B CC genotype (80%) had higher SVRs than those with the CT/TT (56%) genotype (P = 0.010). Multivariate analysis showed that TW8 and TW12 responses were independent predictors of SVR. Serious adverse events occurred in 18.6%: sepsis (2%), decompensation (2.7%) and blood transfusion (14%). Discontinuations occurred in 30.7%, with 18.6% fulfilling stopping rules. CONCLUSION: Boceprevir can be used successfully in PR treatment failures with a SVR12 > 80% if they have good on-treatment responses; however, discontinuations occurred in 30% because of virological failure or adverse events.

Peginterferon alfa-2b in the treatment of Chinese patients with HBeAg-positive chronic hepatitis B: a randomized trial.

BACKGROUND: In mainland China, peginterferon (PEG-IFN) alfa-2b 1.0µg/kg/wk for 24 weeks is the approved treatment for HBeAg-positive chronic hepatitis B. OBJECTIVE: This multicenter, randomized trial evaluated the safety and efficacy of regimens utilizing increased dose or treatment duration in treatment-naive Chinese patients with chronic hepatitis B. STUDY DESIGN: 670 HBeAg-positive patients from China, Malaysia, Taiwan area, Singapore, and Thailand were enrolled. Patients received PEG-IFN alfa-2b 1.0µg/kg/wk (arm A) or 1.5µg/kg/wk (arm B) for 24 weeks, or 1.5µg/kg/wk for 48 weeks (arm C). The primary end point was loss of HBeAg 24 weeks after end of treatment. RESULTS: At the end of follow-up, HBeAg loss was significantly greater in arm C compared with arm A (31.3% vs. 17.3%; P=0.001) and arm B (31.3% vs. 18.1%; P=0.001). No significant difference in the rate of HBeAg loss was observed between arms A and B. The proportions of patients with HBe seroconversion, HBV DNA levels <20,000IU/mL, and ALT normalization at the end of follow-up were significantly higher in arm C compared with arm A and arm B. In arms A, B, and C, rates of early treatment discontinuation were 6.3%, 4.9%, and 8.9%; of discontinuation due to an AE, 2%, 3%, and 3%; and of AEs requiring dose modification, 3%, 6%, and 10%, respectively. CONCLUSIONS: In Chinese patients with HBeAg-positive chronic hepatitis B, PEG-IFN alfa-2b 1.5µg/kg/wk for 48 weeks is more efficacious compared with 1.0 and 1.5µg/kg/wk for 24 weeks.

Treatment of hepatitis B in decompensated liver cirrhosis.

Chronic hepatitis B infection progresses from an asymptomatic persistently infected state to chronic hepatitis, cirrhosis, decompensated liver disease, and/or hepatocellular carcinoma. About 3% of patients with chronic hepatitis develop cirrhosis yearly, and about 5% of individuals with hepatitis B cirrhosis become decompensated annually. The outcome for patients with decompensated cirrhosis is bleak. Lamivudine, the first oral antiviral agent available for hepatitis B treatment is safe and effective and can improve or stabilize liver disease in patients with advanced cirrhosis and viraemia. Viral resistance restricts its prolonged use. Entecavir and tenofovir are newer agents with excellent resistance profile to date. These and some other antiviral agents are being investigated for optimal use in this rather challenging patient group.

A systematic review of hepatitis C virus epidemiology in Asia, Australia and Egypt.

BACKGROUND: The hepatitis C pandemic has been systematically studied and characterized in North America and Europe, but this important public health problem has not received equivalent attention in other regions. AIM: The objective of this systematic review was to characterize hepatitis C virus (HCV) epidemiology in selected countries of Asia, Australia and Egypt, i.e. in a geographical area inhabited by over 40% of the global population. METHODOLOGY: Data references were identified through indexed journals and non-indexed sources. In this work, 7770 articles were reviewed and 690 were selected based on their relevance. RESULTS: We estimated that 49.3-64.0 million adults in Asia, Australia and Egypt are anti-HCV positive. China alone has more HCV infections than all of Europe or the Americas. While most countries had prevalence rates from 1 to 2% we documented several with relatively high prevalence rates, including Egypt (15%), Pakistan (4.7%) and Taiwan (4.4%). Nosocomial infection, blood transfusion (before screening) and injection drug use were identified as common risk factors in the region. Genotype 1 was common in Australia, China, Taiwan and other countries in North Asia, while genotype 6 was found in Vietnam and other Southeast Asian countries. In India and Pakistan genotype 3 was predominant, while genotype 4 was found in Middle Eastern countries such as Egypt, Saudi Arabia and Syria. CONCLUSION: We recommend implementation of surveillance systems to guide effective public health policy that may lead to the eventual curtailment of the spread of this pandemic infection.

Asian-Pacific consensus statement on the management of chronic hepatitis B: a 2008 update.

Large amounts of new data on the natural history and treatment of chronic hepatitis B virus (HBV) infection have become available since 2005. These include long-term follow-up studies in large community-based cohorts or asymptomatic subjects with chronic HBV infection, further studies on the role of HBV genotype/naturally occurring HBV mutations, treatment of drug resistance and new therapies. In addition, Pegylated interferon alpha2a, entecavir and telbivudine have been approved globally. To update HBV management guidelines, relevant new data were reviewed and assessed by experts from the region, and the significance of the reported findings were discussed and debated. The earlier "Asian-Pacific consensus statement on the management of chronic hepatitis B" was revised accordingly. The key terms used in the statement were also defined. The new guidelines include general management, special indications for liver biopsy in patients with persistently normal alanine aminotransferase, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patients receiving immune-suppressive medications or chemotherapy and patients in the setting of liver transplantation, are also included.

A double-blind placebo-controlled study of emtricitabine in chronic hepatitis B.

BACKGROUND: Emtricitabine is a nucleoside analogue approved for treatment of human immunodeficiency virus 1 with clinical activity against hepatitis B virus (HBV). METHODS: To compare the safety and efficacy of emtricitabine with placebo in patients with HBV, we conducted a randomized (2:1), double-blind study at 34 sites in North America, Asia, and Europe that enrolled adults between November 2000 and July 2002 who had chronic HBV infection but had never been exposed to nucleoside or nucleotide treatment. Each patient received either 200 mg of emtricitabine (n=167) or placebo (n=81) once daily for 48 weeks and underwent a pretreatment and end-of-treatment liver biopsy. Histologic improvement was defined as a 2-point reduction in Knodell necroinflammatory score with no worsening in fibrosis. RESULTS: At the end of treatment, 103 (62%) of 167 patients receiving active treatment had improved liver histologic findings vs 20 (25%) of 81 receiving placebo (P<.001), with significance demonstrated in subgroups positive (P<.001) and negative (P=.002) for hepatitis Be (HBe) antigen. Serum HBV DNA readings showed less than 400 copies/mL in 91 (54%) of 167 patients in the emtricitabine group vs 2 (2%) of 81 in the placebo group (P<.001); alanine aminotransferase levels were normal in 65% (109/167) vs 25% (20/81), respectively (P<.001). At week 48, 20 (13%) of 159 patients in the emtricitabine group with HBV DNA measured at the end of treatment had detectable virus with resistance mutations (95% confidence interval, 8%-18%). The rate of seroconversion to anti-HBe (12%) and HBe antigen loss were not different between arms. The safety profile of emtricitabine during treatment was similar to that of placebo. Posttreatment exacerbation of HBV infection developed in 23% of emtricitabine-treated patients. CONCLUSION: In patients with chronic HBV, both positive and negative for HBe antigen, 48 weeks of emtricitabine treatment resulted in significant histologic, virologic, and biochemical improvement.

Treatment of chronic hepatitis B infection using interferon.

Four to 6 months of conventional interferon alpha (IFN-alpha) (5MU daily or 10MU three times weekly) resulted in HBeAg loss in approximately 33% of HBeAg positive patients (controls: 12%). Longer treatment duration improved HBeAg seroconversion. Children with chronic HBV infection and high ALT respond to IFN-a at similar rates. Good end-of-treatment (ET) biochemical and virological response were also achieved with IFN-alpha in HBeAg negative, HBV-DNA positive hepatitis patients. Sustained response (SR) however, was disappointing, but improved with longer duration of treatment: (10-15% SR with 4/6 months treatment: 30% SR with 24 months treatment). Weekly pegylated IFN-alpha2a (PegIFN-alpha2a) for 24 weeks gave a significantly higher HBeAg conversion rate (33%) than conventional IFN-alpha2a (25%). Fifty-two weeks of PegIFN-alpha2b gave a sustained HBeAg loss in 35% patients and HBeAg seroconversion in 29% patients. Similar results were obtained with 48 weeks of weekly PegIFN-alpha2a. PegIFN-alpha2a monotherapy was found to be superior to lamivudine monotherapy in affecting a 6-month SR (normal ALTs and HBV DNA < 20,000 copies/mL) in HBeAg negative/anti-HBe positive chronic hepatitis B patients. There is a tendency for IFN-a and lamivudine combination to result in better sustained response than lamivudine monotherapy. This tendency is also observed with PegIFN-a and lamivudine combination although the combination did not appear to be better than PegIFN-alpha monotherapy. IFN induced HBeAg seroconversion is durable, could increase over time and resulted in better overall survival and survival free of hepatic decompensation or hepatocellular cancer. The main advantage of IFN-a therapy is that a course of finite duration may achieve sustained off-therapy response in a proportion of both HBeAg positive and HBeAg negative chronic hepatitis B patients. However, IFN treatment is usually associated with side-effects, especially flu-like symptoms, fatigue, neutropenia, thrombocytopenia and depression. These are usually tolerable but may require dose modification and premature cessation of treatment (5%). Interferon therapy induced hepatitis flares may lead to decompensation in patients with cirrhosis and can be dangerous in patients with decompensated liver function despite dose reduction.

Treatment of chronic hepatitis B in HIV co-infected patients.

In the Asia Pacific region Human Immunodeficiency virus (HIV) is often acquired in individuals already infected with hepatitis B virus (HBV). The immune suppression caused by HIV infection reduces cellular immune response against HBV and liver inflammation may improve, but the risk of developing cirrhosis is not. HBV infection does not affect the progression of HIV disease. Anti-retroviral agents may be directly hepatotoxic and cause ALT elevations in patients with chronic hepatitis. Highly active anti-retroviral therapy (HAART) improves immunity and as cytotoxic lymphocyte responses improve, hepatitis flares can occur, usually r within 3 months of initiation of HAART. These hepatitis flares may be followed by normalization of ALT and clearance of HBVDNA. If lamivudine is included in the HAART regime, hepatitis flares may not occur till late and these late flares signal the development of lamivudine resistant HBV strains (90% of HBV/HIV co-infection). Treatment options for chronic HBV infection include interferon (IFN), and nucleoside analogues. Lamivudine, adefovir dipivoxil, tenofovir disoproxil fumarate (DF) are nucleoside analogues with activity against both HBVDNA polymerase and HIV reverse transcriptase. The latter two compounds have added activity against lamivudine resistant HBVDNA. Lamivudine should be avoided in the initial treatment of both hepatitis B as well as HIV because of the high incidence of resistance. Interferon should be considered first for treatment of HBV in HIV co-infected individuals and is usually unsuccessful in the later stages of HIV infection when immune suppression is extreme. As new and improved agents in HAART continue to prolong survival, the use of liver transplantation for cirrhotic patients co-infected with HIV and HBV may increase.

Asian-Pacific consensus statement on the management of chronic hepatitis B: a 2005 update.

BACKGROUND/AIMS: A large amount of new data on the treatment of chronic hepatitis B has become available such that the 2003 consensus statement requires revision and update. METHODS: New data were presented, discussed and debated in an expert pre-meeting to draft a revision. The revised contents were finalized after discussion in a general meeting of APASL. RESULTS: Conceptual background, including the efficacy and safety profile of currently available and emerging drugs, was reviewed. Nineteen recommendations were formed and unresolved issues and areas for further study were suggested. CONCLUSION: The current therapy of chronic hepatitis B is modestly effective but not satisfactory. The development of new drugs and new strategies is required to further improve the outcomes of treatment.

Four years of lamivudine treatment in Chinese patients with chronic hepatitis B.

BACKGROUND AND AIMS: This study assessed the efficacy and safety of up to 4 years of lamivudine treatment and the clinical relevance of the emergence of YMDD-variant hepatitis B virus (HBV). METHODS: Fifty-eight Chinese adult patients with chronic hepatitis B (CHB) were randomized to lamivudine 100 mg/day for up to 5 years and were monitored for YMDD-variant HBV, hepatitis B e antigen (HBeAg) seroconversion (loss of HBeAg and detectable antibody to HBeAg) and serum alanine aminotransferase (ALT) concentrations. Four-year data are reported here. RESULTS: The rate of HBeAg seroconversion increased with extended therapy and also with higher baseline ALT concentrations. YMDD-variant HBV was detected in 67% (39/58) of patients at some point during treatment. After 4 years, a total of 47% (27/58) of patients achieved HBeAg seroconversion. Thirty-three per cent (13/39) of patients with YMDD-variant HBV achieved HBeAg seroconversion; this increased to 57% (8/14) in patients with moderately elevated (>2-5 x upper limit of normal) pre-treatment ALT concentrations. The proportion of patients that achieved normal serum ALT increased from 29% (17/58) at baseline to 69% (31/45) following 4 years of treatment. That included 68% (23/34) of patients with YMDD-variant HBV and 73% (8/11) of those without the variant. All patients receiving lamivudine had reduced serum concentrations of HBV-DNA compared with baseline, despite the emergence of YMDD-variant HBV in 39 patients. Lamivudine was generally well tolerated; there was little change in the number or type of drug-related adverse events in the fourth year of the study. CONCLUSIONS: Despite the emergence of YMDD-variant HBV, Chinese patients showed increased HBeAg seroconversion and improvement in ALT levels with an increased duration of treatment with lamivudine.

Practical difficulties in the management of hepatitis B in the Asia-Pacific region.

The Asia-Pacific Expert Committee on Hepatitis B Management recently reviewed the impact of hepatitis B in the region and assessed the differences and similarities observed in the practical management of the disease in individual Asia-Pacific countries. Hepatitis B is a major health concern in the Asia-Pacific region, and of all chronically infected carriers worldwide, approximately 75% are found in Asia. The disease poses a considerable burden on healthcare systems, and is likely to remain a cause of substantial morbidity and mortality for several decades. Disease prevention activities, including screening and vaccination programs, have been implemented successfully in some Asia-Pacific countries and similar measures are being established in other parts of the region. The management of hepatitis B in the Asia-Pacific varies throughout the region, with each country confronting different issues related to treatment options, disease monitoring and duration of therapy. The influence of cost, availability of diagnostic equipment, and patient awareness and compliance are of additional concern. Although guidelines such as those developed by the Asian Pacific Association for the Study of the Liver have been created to address problems encountered in the management of hepatitis B, many physicians in the region still find it difficult to make satisfactory management decisions because of the treatment choices available. This article examines the different approaches to hepatitis B management in a number of Asia-Pacific countries, and highlights the difficulties that can arise when adhering to treatment guidelines and disease prevention solutions that have proved to be successful in the region.