Clinical outcome after cessation of nucleos(t)ide analog treatment in chronic hepatitis B patients who achieved HBsAg seroclearance

Background We determined the long-term clinical outcome and the durability of treatment cessation after HBsAg seroclearance following nucleos(t)ide analog (NA) therapy in patients with chronic hepatitis B (CHB). Methods We analyzed virological relapse (VR), HBsAg reversion, clinical relapse, and changes in HBsAg and HBcrAg levels by iTACT assay after treatment cessation of 90 CHB patients who achieved HBsAg seroclearance by NA treatment. Results Median age of patients at treatment cessation was 57 years. Median duration of NA treatment and follow-up from cessation of NA were 9.25 and 5.2 years, respectively. Although VR occurred in 19 of 90 (21.1%) patients, HBV DNA levels of 18 patients had temporal elevations and sustained levels under the detection level thereafter. HBsAg reversion using Architect HBsAg QT assay occurred in six patients (6.7%) after cessation of NA. Five patients had temporal HBsAg level elevations and sustained levels under the detection level thereafter. One patient had virological and clinical relapse at 6 months after cessation of NA, and received NA re-treatment. HBsAg levels by iTACT assay from end of treatment (EOT) gradually decreased and in 18 of 28 (64%) patients reached an undetectable level at 5 years after EOT. In contrast, HBcrAg levels by iTACT assay slowly decreased, and in 8 of 29 patients (28%) reached an undetectable level at 5 years after EOT. Conclusions Patients receiving NA treatment who achieved HBsAg seroclearance as determined by HBsAg QT assay rarely experienced virological or clinical relapse after the cessation of treatment.