JAK Inhibitor Upadacitinib Induces Remission in Refractory Immune‐Related Colitis Triggered by CTLA‐4 and PD‐1 Inhibitor Combination Therapy in Malignant Pleural Mesothelioma: A Case Report

Abstract

ABSTRACT Background Immune checkpoint inhibitors have demonstrated efficacy against various cancers; however, there is a rising incidence of immune‐related colitis. Some cases of immune‐related colitis prove resistant to treatment, even with the administration of glucocorticoids or infliximab, and there is currently no established standard treatment for such cases. Case The patient, a 73‐year‐old male, had undergone combination therapy for malignant pleural mesothelioma for 2 years, utilizing both ipilimumab (a CTLA‐4 inhibitor) and nivolumab (a PD‐1 inhibitor). Unfortunately, the treatment led to side effects, specifically immune‐related adverse event (irAE) enterocolitis. Steroid and infliximab treatment failed to improve the patient's condition. Treatment with tacrolimus was attempted, but the patient remained unresponsive. Subsequently, 45 mg of upadacitinib, a Janus kinase (JAK) inhibitor, was administered. Symptoms improved rapidly following upadacitinib administration, and endoscopy also revealed positive results. With the increasing incidence of immune‐related colitis, some patients have become resistant to treatment with glucocorticoids and infliximab. In this case, the irAE enterocolitis was improved by upadacitinib administration. Conclusion In cases where immune‐related colitis proves resistant to treatment with glucocorticoids, infliximab, or tacrolimus, upadacitinib represents a potential option as a JAK inhibitor.

Keywords

• CTLA‐4 inhibitor
• irAE
• JAK inhibitor
• PD‐1 inhibitor
• upadacitinib