Quantitative real time pcr

HBV DNA was detected using quantitative real-time PCR (Sansure Biotech Inc., Hunan, China) and a Roche Light cycler 480 (Roche Corporation, Basel, Switzerland). HBsAg and HBeAg were quantified using an automated chemiluminescent microparticle immunology analyzer (Abbott I2000, Abbott Laboratories, Chicago, IL, USA). Alanine aminotransferase (ALT) was quantified using an automatic biochemical analyzer ADVIA 2400 (Siemens, Munich, Germany).

The patients are enrolled in a retrospective study based on a multi-center, randomized controlled phase III clinical trial from March 2013 to July 2015. A total of 855 HBeAg-positive CHB patients were taken as candidates and were randomized to the PegIFN α-2a group (Pegasys®, Roche, Switzerland) or PegIFN α-2b (PegBeron®, Amoytop Biotechnology, China) group by a ratio of 1:2. Patients received 48 weeks of treatment (180 μg/week) and 24 weeks of follow-up. Those candidates who failed to finish the entire study and whose serum samples were unavailable were excluded, finally, 650 patients were finally qualified for this study (The patient flow chart of this study is shown in Graphical abstract. HBsAg, HBeAg, and anti-HBe were measured using serially collected serum (Roche Diagnostics, Switzerland), HBV pgRNA was extracted from patient serum samples (200 μL) using a nucleic acid extraction kit (Sansure Biotech Inc. China) which was developed based on the magnetic bead technology, and HBV DNA was detected using quantitative real-time PCR (Sansure Biotech Inc. Hunan, China).