Variability in long-term hepatitis B virus dynamics under antiviral therapy.

Hepatitis B virus (HBV) dynamics in treated patients can be complex and differ considerably from other viral infections. We analyse dynamics of liver and serum levels of HBV DNA in 24 chronically HBV-infected individuals undergoing 1 year of combination therapy with pegylated interferon alpha and adefovir dipivoxil (ADV), followed by 2 years of ADV monotherapy. Serum viral dynamics differentiated the patients into four response groups dependent on how quickly viremia became undetectable: quickly suppressed (HBV DNA <100 copies/ml within 8 weeks and staying suppressed, GRP1); quickly suppressed but some rebound (<10,000 copies/ml, GRP2); slow decay (GRP3); virological failures (>10,000 copies/ml, GRP4). These groups did not differ before start of therapy by serum HBV DNA (p=0.2), HBsAg (p=0.1), ALT (p=0.4), total HBV DNA within the liver (p=0.08), or cccDNA (p=0.3). Despite very different serum HBV DNA levels after 3 years, there was no statistical difference in total HBV DNA within the liver (p=0.08), nor in cccDNA levels (p=0.1), but HBsAg levels in serum were significantly lower for GRP1 compared to GRP4 (p=0.02). Efficacy in terms of reduction over the 3 years of serum HBV DNA, liver HBV DNA, cccDNA, and ratios of liver HBV DNA to cccDNA were 99.98%, 99.5%, 98.4%, and 83.2% respectively, exhibiting larger antiviral effects in serum than in liver. Over the course of therapy, HBV DNA viremia exhibited large oscillations for some individuals. Mathematical modelling reproduced the dynamics of these diverse groups by assuming a number of viral clones arose that experienced delayed recognition by the antibody response. Large viremia oscillations under therapy suggest sequential outgrowth of viral clones with delayed recognition by the humoral response.

Telbivudine plus pegylated interferon alfa-2a in a randomized study in chronic hepatitis B is associated with an unexpected high rate of peripheral neuropathy.

BACKGROUND & AIMS: This study investigated the antiviral efficacy and safety of telbivudine in combination with pegylated interferon (PegIFN) alpha-2a in chronic hepatitis B (CHB) patients. METHODS: This was a randomized, open-label, multicentre study, in treatment-naïve patients with HBeAg-positive CHB, comparing the efficacy and safety of telbivudine in combination with PegIFN alpha-2a with telbivudine monotherapy and PegIFN alpha-2a monotherapy. The study was terminated early due to increased rates of peripheral neuropathy in the combination-therapy group. RESULTS: Of the 159 patients randomized (from 300 planned) 50 were assigned to combination therapy, 55 to telbivudine, 54 to PegIFN, and 110 (18, 49, and 43, respectively) reached week 24. Peripheral neuropathy occurred in 7/50, 1/54, and 0/54 patients in the three groups of safety populations, respectively. No relationship between the occurrence of peripheral neuropathy and other variables (e.g., pharmacokinetic data, treatment efficacy, ALT levels, creatine kinase elevations) were observed. At week 24, undetectable HBV DNA (<300 copies/ml) was achieved by 71% (12/17), 35% (17/48), and 7% (3/42) of patients, with available data receiving combination therapy, telbivudine monotherapy and PegIFN monotherapy, respectively (p = 0.022 for combination therapy vs. telbivudine; p<0.0001 for combination therapy vs. PegIFN). CONCLUSIONS: Combination therapy carried an increased risk of peripheral neuropathy. Despite the rapid and profound reductions in HBV DNA levels, combination therapy with telbivudine and PegIFN should not be used.

Temporary HBV resolution in an HIV-coinfected patient during HBV-directed combination therapy followed by relapse of HBV.

Coinfection of hepatitis B virus (HBV) and HIV is common due to overlapping routes of transmission accompanied by an increased risk for liver-related mortality. We report the case of a chronically infected hepatitis Be antigen positive patient, coinfected with HIV (CD4+ T-cell count > 500 cells/microl), with histological evidence of advanced liver disease. The patient developed anti-HBs (antibody to hepatitis B surface antigen [HBsAg]) seroconversion, a strong reduction of intrahepatic covalently closed circular DNA and a marked improvement of liver histology after 24 weeks of HBV-targeted combination therapy with adefovir dipivoxil and pegylated interferon-alpha2b followed by another 12 weeks of adefovir dipivoxil monotherapy. Antiviral therapy was stopped after the development of stable anti-HBs titres, and anti-HBs titres remained stable for additional 9 months post-treatment. A continuous decline of anti-HBs was observed during the next 6 months until anti-HBs disappeared despite a stable HIV infection. A triple course of therapeutic vaccination failed to re-establish anti-HBs antibodies, but reappearance of HBV DNA and HBsAg was detected. By enzyme-linked immunosorbent spot analyses, HBV-directed T-cell responses clearly increased during antiviral combination therapy followed by a reduction to pre-treatment levels in association with disappearance of anti-HBs antibodies despite therapeutic vaccination. The presented case highlights the volatile nature of chronic HBV infection even after a prolonged disease-free period in the setting of an underlying HIV coinfection in a patient with a stable and relatively high CD4+ T-cell count but nevertheless impaired immune system and calls for further investigation of probably temporary immunomodulatory effects of interferon-alpha and/or nucleoside analogues in immunocompromised patients.

Peginterferon alpha-2b plus adefovir induce strong cccDNA decline and HBsAg reduction in patients with chronic hepatitis B.

Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) is responsible for persistent infection of hepatocytes. The aim of this study was to determine changes in intrahepatic cccDNA in patients with chronic hepatitis B (CH-B) during 48 weeks of antiviral therapy and its correlation to virological, biochemical, and histological parameters. Twenty-six HBsAg-positive CH-B patients received combination treatment with pegylated interferon alpha-2b (peg-IFN) and adefovir dipivoxil (ADV) for 48 weeks. Paired liver biopsies from before and at the end of treatment were analyzed for intrahepatic HBV-DNA. Median serum HBV-DNA had decreased by -4.9 log10 copies/mL at the end of treatment and was undetectable in 13 individuals (54%). Median intrahepatic total HBV-DNA and cccDNA had decreased by -2.2 and -2.4 log10, respectively. Changes in intracellular HBV-DNA positively correlated with HBsAg serum reduction and were accompanied by a high number of serological responders. Eight of 15 HBeAg-positive patients lost HBeAg, and five developed anti-HBe antibodies during treatment. These eight patients exhibited lower cccDNA levels before and at the end of therapy than did patients without HBeAg loss. Four patients developed anti-HBs antibodies. ALT normalized in 11 patients. The number of HBs-antigen- and HBc-antigen-positive hepatocytes was significantly lower after treatment, suggesting the involvement of cytolytic mechanisms. In conclusion, combination therapy with peg-IFN and ADV led to marked decreases in serum HBV-DNA and intrahepatic cccDNA, which was significantly correlated with reduced HBsAg.