A case of chronic hepatitis B which achieved hepatitis B surface antigen seroclearance during combination therapy with peginterferon alfa-2b and entecavir

Abstract

A 65-year-old Japanese male with chronic hepatitis B (CH-B) diagnosed in December 2008 was referred to our department in July 2009. He started combination therapy with peginterferon alfa-2b (80 μg/week) and entecavir (0.5 mg/day) for 48 weeks from December 2009. At the initiation of therapy, his significant laboratory test results were as follows: alanine aminotransferase (ALT) 55 IU/l, aspartate aminotransferase (AST) 37 IU/l, hepatitis B surface antigen (HBsAg) positive, hepatitis B e antigen (HBeAg) positive, hepatitis B virus (HBV) DNA levels 7.9 Log copies/ml. HBV DNA, HBsAg and HBeAg levels decreased progressively with therapy. After 36 weeks, HBV DNA, AST and ALT levels flared up, but after 44 weeks, HBV DNA levels decreased below 2.1 Log copies/ml and HBeAg seroconversion and HBsAg seroclearance were achieved. After 72 weeks he maintained HBsAg seroclearance and achieved a sustained viral response. Cases of spontaneous HBsAg seroclearance have been reported previously, but HBsAg seroclearance caused by combination therapy with peginterferon alfa-2b and entecavir has not been reported. Pre- and post-treatment cccDNA load in liver tissue, hepatitis B virus core-related antigen (HBcrAg) concentration in serum and expression of hepatitis B core antigen (HBcAg) in hepatocyte were compared, and it was found that all were drastically decreased. The present study suggests that these reduction appeared to contribute to the successful outcome of this therapy.