Predictors of liver histological changes and a sustained virological response to peginterferon among chronic hepatitis B e antigen-positive patients with normal or minimally elevated alanine aminotransferase levels.

A proportion of chronic hepatitis B patients with normal or only minimally elevated alanine aminotransferase (ALT) levels display significant histologic changes and would benefit from antiviral therapy. We aim to evaluate the histologic abnormalities seen in these patients and then determine which of them would most likely respond to peginterferon therapy. One hundred and thirteen hepatitis B e antigen (HBeAg)-positive patients with a normal or minimally elevated ALT level and moderate-to-severe histologic changes in their liver tissue were selected to receive peginterferon monotherapy and participate in a follow-up analysis. A multiple logistic regression analysis indicated that increasing age (P=.049) and lower hepatitis B virus (HBV) DNA levels (P=.038) were associated with significant histological abnormalities in patients with a normal or minimally elevated ALT. Our predictive model which incorporated HBeAg testing at treatment week 12 combined with hepatitis B surface antigen (HBsAg) testing at treatment week 24 was able to identify which patients with a normal ALT level would achieve a sustained virological response (SVR) (positive predictive value [PPV]: 66.7%, negative predictive value [NPV]: 90.0%). Lower HBsAg and HBeAg levels at treatment week 24 were associated with a SVR in patients with a minimally elevated ALT level (PPV: 100.0%, NPV: 100.0%). A liver biopsy and antiviral therapy should be strongly considered when treating HBeAg-positive patients with a normal or minimally elevated ALT level, low HBV DNA level, and aged >35 years. On-treatment quantification of combined HBsAg and HBeAg test results may be useful for predicting a SVR to peginterferon monotherapy in these patients.

Metformin inhibits hepatitis B virus protein production and replication in human hepatoma cells.

Hepatitis B virus surface antigen (HBsAg) plays an important role in maintaining the tolerance and may interfere with host innate and adaptive immune responses; therefore, novel therapeutic strategies to reduce HBsAg loads in patients infected with hepatitis B virus (HBV) are emerging as an attractive but challenging issue. Metformin could regulate hepatic metabolism while the latter interacts with HBV infection. We hypothesized that metformin could affect HBsAg expression and HBV replication and may work synergistically when combined with current antivirals. In our study, a notably inhibitory effect on HBsAg production, as well as a moderate inhibition in HBV replication and HBeAg expression was observed following metformin treatment. The 50% effective concentration (EC50) for extracellular HBsAg and intracellular HBsAg in HBV-producing HepG2.2.15 cells was 2.85 mm and 2.75 mm, respectively, with a similarly selective index of about 18. When administered in combination, metformin enhanced the inhibitory effects of interferon-α2b on HBsAg expression and HBV replication and provided a complimentary role in HBsAg expression for lamivudine (LMV). This novel action of metformin derives partially from its inhibition on multiple HBV cis-acting elements. By the virtues of preferably hepatocyte distribution and safety profile, collectively, our results suggest that metformin would be potentially clinically helpful as an HBsAg production inhibitor.