Patients with HBsAg <1500 IU/ml treated with nucleotide antiviral drugs have a high probability of clinical cure by switching to long-acting interferon Disease: HBeAg-positive chronic hepatitis B (hepatitis B major triplet) Description: Male, 33 years old, employee, with good economic income. Before 2006, he was found to be HBsAg positive in a physical examination, but liver function tests showed that transaminases had been fluctuating within the normal range, so the patient did not pay attention to it. In February 2009, a physical examination of liver function showed elevated transaminases, which fluctuated repeatedly, with ALT mostly between 150-350 U/L, accompanied by repeated weakness, feeling tired and poor appetite. Diagnosis: HBeAg-positive chronic hepatitis B. Underwent entecavir antiviral therapy for 2 years and 6 months, virus turned negative, transaminases returned to normal range, HBsAg 1350 IU/ml. Treatment expectation: I will take oral medication for the rest of my life, according to my current treatment status is there any treatment plan to replace long-term medication and achieve clinical cure Examination and medication status: Diagnosis: Chronic hepatitis B virus negative, but oral medication needs to be taken for a long time. History: After 2 years and 6 months of oral antiviral medication, long-acting interferon combination therapy was added in August 2010 for 2 months followed by interferon monotherapy until December 2012. Examination: Virology: HBV DNA <5E+2 copies/mL; Serology: HBsAg(-), HBsAb(-), HBeAg(-), HBeAb(-), HBcAb(+); Biochemistry: ALT 33 U/L, AST elevated (35 U/L ), γ-GT 28 U/L. Treatment course: Patient was young, had previous antiviral The patient had a history of antiviral treatment, normal baseline ALT levels and negative HBV DNA, suggesting that chronic hepatitis B was under control and the surface antigen level was low. After administration of pegylated interferon-2a, HBV DNA was negative at the 1st, 3rd, 6th and 9th month of examination, and liver function was normal, while HBsAg quantification continued to decrease; HBsAg clearance occurred after 1 year of treatment (standard course of treatment, i.e. 48 weeks). Follow-up after discontinuation has been more than 1 year, and HBeAg serological conversion and HBsAg serological conversion were always maintained, and liver function was within the normal range. At the time of the first injection, the patient had fever and muscle pain, which improved after three days. At the beginning of treatment, there was a decrease in leukocytes and two injections of colony-stimulating factor, followed by one month of riclosant, without other abnormalities, which did not affect the treatment. Expert summary: For young patients and have the requirement to stop medication, if HBsAg <1500 IU/ml patients prefer to switch to pegylated interferon treatment, it is expected to achieve a limited course of antiviral therapy, and even expected to obtain HBsAg clearance and achieve a state of clinical cure. During pegylated interferon treatment, the change of HBsAg quantification helps to judge the efficacy. Patients whose HBsAg quantification decreases more significantly during the treatment period can extend the course of treatment appropriately and are expected to obtain better efficacy.