HBeAg-negative chronic hepatitis B (CHB) patients with low Level HBsAg and with a history of drug resistance or suboptimal/partial virological response were enrolled. After giving informed consent, patients were treated with nucleoside analog(s) (NAs) once a day and weekly subcutaneous injections of alfa-2a 180 micrograms/week or peginterferon alfa-2b 80 micrograms/week for 12 weeks. 12 weeks later, NAs was stopped, patients were treated with weekly subcutaneous injections of alfa-2a 180 micrograms/week or peginterferon alfa-2b 80 micrograms/week. Treatment endpoint was HBsAg loss(<0.05 IU/mL).

It is estimated that more than 400 million people are infected with hepatitis B virus (HBV) globally. HBeAg-negative CHB patients with low Level HBsAg and with a history of drug resistance or suboptimal/partial virological response were enrolled in the out-patient department of 3rd Affiliated Hospital of Sun Yat-sen University. All of them were HBsAg positive and anti-HBs negative for more than 6 months with HBV DNA<100 IU/mL and HBsAg levels <1000 IU/mL. All patients did not have other liver diseases and contraindications for interferon therapy.

After giving informed consent, patients were treated with NAs once a day and weekly subcutaneous injections of alfa-2a 180 micrograms/week or peginterferon alfa-2b 80 micrograms/week for 12 weeks. 12 weeks later, NAs was stopped, patients were treated with weekly subcutaneous injections of alfa-2a 180 micrograms/week or peginterferon alfa-2b 80 micrograms/week. The use of other immune suppressive or regulatory drugs and other antiviral drugs was prohibited during the course of the study.

In this study, treatment endpoint was HBsAg loss(<0.05 IU/mL).Anti-HBs positive(>10 milli-International unit)(mIU/mL) defined as seroconversion. Depending on the decline of HBsAg level, treatment was either continued for a prolonged period (no more than 96 weeks) until the endpoint was achieved, or terminated in case of nonresponse.

Inclusion Criteria:

1. CHB patients who had received single NAs for more than 12 months and had a history of NAs drug resistance or suboptimal/partial virological response.
2. Hepatitis B e antigen (HBeAg)-negative.
3. Hepatitis B surface antigen (HBsAg) positive and <1000 IU/mL.
4. Hepatitis B virus DNA <100 IU/mL.

Exclusion Criteria:

1. Patients with liver cirrhosis, Hepatocellular Carcinoma or alpha feto protein (AFP) >2 upper limit of normal(ULN) or other malignancies.
2. Patients with other factors causing liver diseases.
3. Pregnant and lactating women.
4. Patients with concomitant HIV infection or congenital immune deficiency diseases.
5. Patients with diabetes, autoimmune diseases.
6. Patients with important organ dysfunctions.
7. Patients with serious complications (e.g., infection, hepatic encephalopathy, hepatorenal syndrome, gastrointestinal bleeding.)
8. Patients who receive antineoplastic or immunomodulatory therapy in the past 12 months.
9. Patients with a previous use of IFN anti hepatitis B virus treatment.
10. Patients who can't come back to clinic for follow-up on schedule.