Association of Bcr-Abl Tyrosine Kinase Inhibitors With Hepatitis B Virus Reactivation Requiring Antiviral Treatment in Taiwan.

Importance: The US Food and Drug Administration (FDA) highlighted the potential risk of hepatitis B reactivation that was associated with Bcr-Abl tyrosine kinase inhibitor (TKI) treatment and has required updated product labels. Objective: To examine the association between hepatitis B flare and exposure to Bcr-Abl TKIs compared with non-Bcr-Abl TKIs. Design, Setting, and Participants: This nested case-control study included patients who entered a hepatitis B carrier cohort in Taiwan after January 1, 2005. Patients who received their first antiviral agents for hepatitis B flare for more than 28 days after the cohort entry date were included as case patients. For each case, a corresponding risk set was formed that included all eligible patients in the study cohort who had the same age (within 1 year), same sex, and were at risk of developing hepatitis B flare at the case date. As many as 10 control patients were randomly selected from the risk set for each case patient. TKIs were evaluated before the hepatitis B flare for case patients and before the corresponding index date for control patients. Data were collected from the Taiwan National Health Insurance research database from January 2000 to 2015. Data analysis was conducted from January to June 2019. Exposure: Use of Bcr-AbL TKIs. Main Outcomes and Measures: Conditional logistic regression was used to estimate the rate ratio for the association between hepatitis B flare and exposure to Bcr-Abl TKIs compared with non-Bcr-Abl TKIs. Results: Among 698 342 patients who carried incident hepatitis B virus, 66 702 patients with hepatitis B flare that required antiviral treatment (47 492 [71.2%] men; mean [SD] age at index date, 50.2 [13.8] years) were included as case patients, and 666 989 age and sex-matched patients (474 903 [71.2%] men; mean [SD] age, 50.2 [13.8] years) were included as control patients. Analysis revealed that Bcr-Abl TKI use during the previous 90 days was independently associated with a 56% higher risk of hepatitis B flare (adjusted rate ratio [aRR], 1.56; 95% CI, 1.11-2.20), and the aRR increased to 1.66 (95% CI, 1.20-2.28) for Bcr-Abl TKI use during the previous 365 days. Use of Bcr-AbL TKIs during the previous 60 days was associated with a significantly increased risk of flare among women (aRR, 3.20; 95% CI, 1.70-6.03) but not among men (aRR, 1.14; 95% CI, 0.72-1.81). Conclusions and Relevance: These findings suggest that sex-specific strategies may be needed to monitor for hepatitis B reactivation among patients receiving Bcr-Abl TKIs.