Risk of Hepatitis B Virus Reactivation in Rheumatoid Arthritis Patients Undergoing Tocilizumab-Containing Treatment.
BACKGROUND AND AIM
To investigate the risk of hepatitis B virus reactivation in patients undergoing long-term tocilizumab therapy for rheumatoid arthritis.


METHOD
From January 2011 through August 2019, a total of 97 patients were enrolled in this retrospective study. Clinical data, comedications, and the occurrence of HBV reactivation were recorded.


RESULTS
Seven patients were HBsAg+ (7.2%), 64 were HBsAg-/HBcAb+ (65.9%), and 26 were HBsAg-/HBcAb- (26.8%). The median disease follow-up time was 9 years. TCZ was administered for a median of 29 months. Four patients (4.1%) experienced HBV reactivation after tocilizumab therapy. Of the 7 HBsAg+ patients, 4 received antiviral prophylaxis and had no HBV reactivation; the remaining 3 patients did not receive antiviral prophylaxis, and all 3 (100%) experienced HBV reactivation and hepatitis flare-up. Hyperbilirubinemia occurred in 2 of these 3 patients, with mild prothrombin time prolongation in one. After salvage entecavir treatment, all patients had a favorable outcome. Of the 64 HBsAg-/HBcAb+ patients, only one became positive for serum HBV DNA (2.5 × 107 IU/mL) after 18 months of tocilizumab treatment (1.6%; 1/64). This patient was immediately treated with entecavir, which prevented hepatitis flare-up.


CONCLUSIONS
Tocilizumab is widely used in treating rheumatoid arthritis and has the potential to reduce the mortality rate among severe COVID-19 patients. However, HBV reactivation needs to be considered. HBsAg+ patients have a high risk of HBV reactivation, which could be prevented by antiviral prophylaxis. Although the risk of reactivation is low in HBsAg-/HBcAb+ patients, strict monitoring is necessary.
['Kuo|Meng Hsuan|MH|', 'Tseng|Chih-Wei|CW|0000-0002-6951-4646', 'Lu|Ming-Chi|MC|', 'Tung|Chien-Hsueh|CH|', 'Tseng|Kuo-Chih|KC|', 'Huang|Kuang-Yung|KY|', 'Lee|Chi-Hui|CH|', 'Lai|Ning-Sheng|NS|']
D061067:Antibodies, Monoclonal, Humanized D018501:Antirheumatic Agents D000998:Antiviral Agents D001172:Arthritis, Rheumatoid D006147:Guanine D006510:Hepatitis B Antibodies D006514:Hepatitis B Surface Antigens D006515:Hepatitis B virus D019694:Hepatitis B, Chronic D006801:Humans D012189:Retrospective Studies D012307:Risk Factors D014775:Virus Activation D017735:Virus Latency
Rheumatoid arthritis Tocilizumab HBV reactivation Hepatitis flare-up