Long-term comparisons of the durability of 6 months versus 12 months antiviral therapy for hepatitis B after chemotherapy cessation

Background: Prophylaxis antiviral therapy is recommended for patients with hepatitis B receiving chemotherapy but the ideal treatment duration after chemotherapy cessation needs more evidence for clarification. Aims: This study aimed to compare the relapse rate of short finite intervals of 6 months and 12 months of -nucleos(t)ide analogue (NA) therapy in patients stratified by low hepatitis B virus (HBV)-DNA of < 2000 IU/ml or high HBV DNA of >= 2000 IU/ml. Methods: Patients started tenofovir or entecavir treatment 1 week before chemotherapy and were assigned to different treatment duration groups randomly after stratified by HBV DNA pretreatment: (1) HBV DNA of < 2000 IU/ml at 6-month or 12-month duration; (2)HBV DNA of >= 2000 IU/ml at 6-month or 12-month duration. Virological relapse (VR) was defined as HBV DNA of > 2000 IU/ml, and clinical relapse (CR) was defined as HBV DNA of > 2000 IU/ml and alanine aminotransferase of > 80 IU/L during the follow-up period. The primary endpoint was to compare the durability between groups 1 year after antiviral therapy cessation. The secondary endpoint was VR and CR rate at long-term follow-up after antiviral therapy cessation. Results: This study enrolled 61 patients, and 5 patients were lost to follow-up or tumor recurrence. VR and CR rates were 46.4% and 14.3% at 1-year and 55.3% and 16.1%, at long-term follow-up, respectively. VR and CR rates demonstrated no difference between the groups. Pretreatment HBV DNA at >= 2000 IU/ml and end-of-treatment hepatitis B surface antigen (HBsAg) at >= 500 IU/ml were the predictor of VR (hazard ratio [HR]: 2.98; p = 0.010 and HR: 2.38; p = 0.037). Conclusions: Prolongation from 6 months to 12 months of NA consolidation after chemotherapy cessation did not affect the VR or CR of HBV. High pretreatment HBV DNA and end-of-treatment HBsAg levels could predict VR after antiviral therapy cessation for chemotherapy.