Late-onset Stevens-Johnson syndrome due to nivolumab use for hepatocellular carcinoma.

Nivolumab is a fully human immunoglobulin G4 immune checkpoint inhibitor antibody approved for use in the treatment of several malignancies. Severe side effects such as Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) have only extremely rarely been reported with this drug. We present herein a patient who developed SJS after 16 weeks of therapy with nivolumab. A week prior to this event, he developed a pruriginous papulo-erythematous rash. Prompt recognition of this phenomenon, immune checkpoint inhibitor discontinuation and steroid therapy are necessary steps in order to avoid dismal outcomes.