Effectiveness of a Physician–Pharmacist Collaborative Protocol for Universal Hepatitis B Virus Screening Prior to Chemotherapy in Cancer Patients

Background/Aim: This study investigated the effectiveness of a protocol-based pharmacotherapy management (PBPM) system in preventing hepatitis B virus (HBV) reactivation induced by chemotherapy. Patients and Methods: This protocol requires pharmacists to verify orders for hepatitis B (HB) surface antigen (HBsAg), anti-HB core antibody (HBcAb), anti-HBs antibody (HBsAb), and HBV-deoxyribonucleic acid (DNA) tests before the start of chemotherapy. Pharmacists are also required to enter any missing test orders after confirming them with physicians. We retrospectively compared the implementation rates of HBsAg, HBcAb, HBsAb, and HBV-DNA tests using the chi-squared test across the following three periods: the pre-PBPM system implementation (pre-PBPM) period (July to September 2021; n=203), the ≤6 month post-PBPM system implementation (≤6M post-PBPM) period (November 2021 to April 2022; n=453), and the >6 month post-implementation (>6M post-PBPM) period (May to July 2022; n=245). Results: The implementation rate of HBsAg tests remained at 100% throughout the entire study period. The overall HBsAg positivity rate was 2.0% (18/901). The implementation rates of HBcAb/HBsAb tests increased significantly, from 59.6% (121/203; pre-PBPM period) to 91.2% (413/453; ≤6M post-PBPM period, p<0.001) and to 98.0% (240/245; >6M post-PBPM period, p<0.001). The HBcAb/HBsAb positivity rates and HBV-DNA implementation rates in the respective periods were 33.1% (40/121), 26.9% (111/413), and 23.8% (57/240), and 90.0% (36/40), 89.2% (99/111), and 91.2% (52/57), with no statistically significant differences observed. No cases of HBV reactivation were observed during the study period. Conclusion: Introduction of the PBPM system significantly contributed to the improvement in the implementation rates of HBsAb/HBcAb testing.