Reduction of covalently closed circular DNA with long-term nucleos(t)ide analogue treatment in chronic hepatitis B.

BACKGROUND AND AIMS: Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA), a mini-chromosome essential for HBV replication, is supposed to be resistant to nucleos(t)ide analogue treatment. We investigated the effect of long-term nucleos(t)ide analogue treatment on cccDNA. METHODS: Among 129 patients who had been enrolled in previous international nucleos(t)ide analogue clinical trials and had liver biopsies at baseline and one year after treatment, we recruited 43 patients on long-term continuous treatment for 72 to 145months for a third liver biopsy. Serum HBV DNA, hepatitis B surface antigen (HBsAg) levels, total intrahepatic HBV DNA (ihHBV DNA), cccDNA, HBV pregenomic RNA (pgRNA) as well as histologic changes were examined. RESULTS: At the time of the third biopsy, serum HBV DNA levels were undetectable in all but one patient. The median levels of HBsAg, ihHBV DNA, and cccDNA were 2.88logIU/ml, 0.03copies/cell, and 0.01copies/cell, respectively. Compared to baseline levels, there was reduction of HBsAg levels by 0.54log (71.46%), ihHBV DNA levels by 2.81log (99.84%), and cccDNA levels by 2.94log (99.89%), with 49% having cccDNA levels below the detection limit. One patient had undetectable HBsAg. The median pgRNA level, measured only in the third biopsy, was 0.021copies/cell, with 40% of patients having undetectable pgRNA. CONCLUSIONS: Long-term nucleos(t)ide analogue treatment induced marked depletion of cccDNA in the majority of patients while serum HBsAg levels, though reduced, were detectable in all but one patient. Whether cccDNA depletion is sustained and associated with better patient outcome requires further study. LAY SUMMARY: It is generally presumed that a form of hepatitis B virus DNA, called covalently closed circular DNA (cccDNA), which hides inside the nuclei of liver cells of patients with chronic hepatitis B, cannot be reduced by antiviral treatment. The present study showed that with prolonged treatment (median period 126months), cccDNA can be markedly reduced, with 49% of liver biopsies having undetectable cccDNA. This suggests that viral replication capacity would be very low after prolonged antiviral treatment.

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

UNLABELLED: We aimed to determine the 2-year outcomes of entecavir followed by lamivudine in patients with undetectable viral load (<12 IU/mL) and normal alanine aminotransferase (ALT) after initial entecavir treatment for at least 6 months. Patients were randomly assigned 1:1 to continue with entecavir or switch to lamivudine. Liver biochemistry and hepatitis B virus (HBV) DNA were determined at weeks 0, 4, 12, 24, 48, 72, and 96. Mutational analysis using line-probe assay were performed at weeks 0, 24, 48, and 96 and at the time of HBV DNA relapse. There was no elevation of ALT observed in any patients up to 96 weeks. At 96 weeks of follow-up, 19/25 (76%) patients in the lamivudine arm had persistently undetectable HBV DNA, compared with 25/25 (100%) patients in the entecavir arm. Six patients in the lamivudine arm had HBV DNA >20 IU/mL, occurring at a range of 12 to 96 weeks. Of these, four patients had HBV DNA of less than 100 IU/mL during rebound (three had undetectable HBV DNA after switching back to entecavir), and the remaining two patients had HBV DNA levels of 7,973 and 699 IU/mL. Three patients (12%) had evidence of drug-resistant mutations, of which two patients had rtM204I mutation and one patient had rtM204V mutation. One of these three patients had previous lamivudine exposure before entecavir treatment and one patient had questionable drug compliance. CONCLUSION: Sequential therapy using entecavir followed by lamivudine resulted in virological rebound in 24% of patients after 96 weeks. Prior optimal viral suppression with entecavir did not confer any significant advantage in patients who switched to lamivudine.

Mild-to-moderate elevation of alanine aminotransferase increases liver stiffness measurement by transient elastography in patients with chronic hepatitis B.

OBJECTIVES: Liver stiffness measurement has been shown to be increased in severe acute flares of hepatitis. Whether lesser degree of hepatitis can also increase liver stiffness is not known. The present study aimed to investigate the effect of mild-to-moderate elevations of alanine aminotransferase (ALT) on liver stiffness in chronic hepatitis B. METHODS: Fifty-eight patients with chronic hepatitis B with ALT levels from 1 to 10 × upper limit of normal were recruited. Liver stiffness measurements were performed at the time of ALT elevation, and liver stiffness measurement was repeated once normalization of ALT occurred after antiviral therapy. Liver biopsies were performed in 38 patients. RESULTS: All 58 patients achieved normalization of ALT after antiviral therapy, with a median time of 3 months between the first and second liver stiffness measurement. There was a significantly lower median liver stiffness measurement after commencement of antiviral therapy, with the normalization of ALT levels compared with pre-treatment levels (6.4 vs. 7.9 kPa, respectively; P<0.001). The area under the receiver operator characteristic curve for diagnosing F2 fibrosis in elevated ALT was 0.68, compared with 0.73 after ALT normalization. Twelve (32%) patients would have been misclassified as having cirrhosis using liver stiffness measurements taken at the time of ALT elevation, compared with 16% after normalization of ALT. CONCLUSIONS: Even mild-to-moderate elevation in ALT levels may increase liver stiffness independent of underlying liver fibrosis. Higher levels of ALT were associated with higher discrepancies in liver stiffness. Therefore, the timing of liver stiffness measurement is important.