[Clinical significance of hepatitis B virus pgRNA for deciding antiviral therapy discontinuation in patients with chronic hepatitis B].

Objective: To explore the clinical significance of hepatitis B pregenomic RNA (pgRNA) for deciding antiviral therapy discontinuation in patients with chronic hepatitis B (CHB). Methods: Data of patients with CHB who were treated with long-term antiviral therapy in the Center for Infectious Diseases, West China Hospital of Sichuan University from January 2019 to December 2019 were collected. Drug discontinuity after evaluation of high-sensitivity HBV DNA and HBV pgRNA (HBV DNA ≤20 IU/ml and HBV pgRNA<150 copies/ml) was observed. The prospective observational study on 91 patients with HBeAg-negative CHB was conducted. The clinical conditions were followed up 3, 6 and 12 months after the drug discontinuation. The relationship between HBV pgRNA and relapse after drug discontinuation was analyzed. Results: From observation to 12 months after drug discontinuation, a total of 34 patients (37.4%) had developed recurrence and resumed antiviral therapy, and the cumulative recurrence rate within 12 months of drug discontinuation was 46.8%. Among the relapsed patients, 14 (41.2%) had biochemical breakthroughs, and all achieved good biochemical and virological responses after the resumption of antiviral therapy. The Cox multivariate proportional hazards regression analysis showed that the level of HBV pgRNA before drug discontinuation and the type of antiviral drugs taken were associated with recurrence after drug discontinuation. The risk of recurrence after drug withdrawal in the HBV pgRNA ≤50 copies/ml group was 2.316 times higher than that in the HBV pgRNA negative group (HR=2.316, 95%CI: 1.047-5.126, P=0.038). The risk of recurrence after drug withdrawal in the HBV pgRNA >50 copies/ml group was 3.45 times higher than that in the HBV pgRNA negative group (HR=3.450, 95%CI: 1.338-8.892, P=0.010). Conclusion: HBV pgRNA can be used to predict the risk of recurrence after antiviral therapy discontinuation in patients with CHB. Patients with negative serum HBV pgRNA before drug discontinuation have a relatively low risk of relapse after drug discontinuation, and drug discontinuation is not recommended for patients with HBV pgRNA >50 copies/ml.