Successful Desensitization Treatment with Osimertinib after the Development of Osimertinib-induced Urticaria in a Patient Undergoing Treatment for Non-small Cell Lung Cancer Harboring the EGFR T790M Mutation: A Case Report

Abstract

Some patients discontinue receiving osimertinib for non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) Thr790Met (T790M) mutation due to adverse its effects. We report a case of successful desensitization therapy after osimertinib-induced urticaria. An 85-year-old Japanese woman received osimertinib as third-line therapy for NSCLC with the EGFR T790M mutation. After two days, she developed urticaria of the lower extremities. We started osimertinib desensitization therapy at 0.1 mg/day, which was gradually increased to 40 mg/day. She continued osimertinib for >12 months without adverse effects. Desensitization therapy with osimertinib could be useful for patients experiencing osimertinib-induced urticaria.