Nivolumab Induced Reactivation of Hepatitis B in a Patient with Metastatic Gastric Adenocarcinoma—A Case Report

Background and Clinical Significance: The most common cause of liver toxicity with the use of immune checkpoint inhibitors (ICIs) is autoimmune hepatitis. As most patients with prior viral infections such as hepatitis B and hepatitis C were excluded in trials for the use of ICIs, the safety of ICIs in these patients with active or prior treated hepatitis is unknown. With expanded use of these medications in many malignancies, it is important to understand the risk of viral reactivation with these medications. There are only few case series and reports documenting hepatitis B reactivations with the use of ICIs. Case Presentation: We present a middle-aged woman with a history of treated hepatitis B who presented with metastatic gastric cancer. She was treated with two cycles of 5-FU, oxaliplatin and nivolumab followed by maintenance nivolumab. After 14 months of nivolumab, she developed marked transaminitis and was found to have reactivation of hepatitis B. As autoimmune hepatitis was the initial suspicion, the patient was initiated on prednisone 1 mg/kg with no improvement in transaminases. Due to the significant elevation of HBV DNA, she was diagnosed with hepatitis B reactivation. She was initiated on entecavir with normalization of transaminases and improvement in HBV DNA levels. She was successfully rechallenged with nivolumab with no evidence of recurrent transaminitis or worsening HBV DNA levels. Conclusions: There are case series of HBV reactivation with the use of ICIs. We believe that any patients with known history of HBV should get baseline viral titers prior to initiation of ICIs with serial monitoring of DNA levels. Prospective studies to evaluate risk of reactivation may need to be performed for us to get a better understanding of risks of viral reactivation and potential effects it may have on safety and efficacy of ICIs.