Upadacitinib for anti-TNFα refractory immune checkpoint inhibitor-induced colitis: a case report.

Although immune checkpoint inhibitors have revolutionized oncologic therapy, they are frequently associated with a wide spectrum of immune-related adverse events, most notably immune-mediated colitis (ImC). For cases of moderate-to-severe colitis, treatment typically involves corticosteroids with escalation to biologic agents such as infliximab or vedolizumab when necessary. However, treatment-refractory cases remain a major clinical challenge. We report the case of a 52-year-old woman with triple-negative breast cancer who developed severe ImC after pembrolizumab therapy. Despite high-dose corticosteroids and infliximab, her condition remained refractory. Initiation of upadacitinib, a selective Janus kinase 1 (JAK1) inhibitor, led to rapid clinical improvement and complete endoscopic remission of the colitis. This report highlights the therapeutic potential of upadacitinib against ImC, while also analysing the possible twofold role of JAK1-inhibitors in enhancing antitumour therapy efficacy and limiting the potential immune-related adverse events.