Supplementary Material for: Successful treatment with osimertinib based on therapeutic drug monitoring in a hemodialysis patient with non-small cell lung cancer: a case report

Although osimertinib is a key drug in the treatment of non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutation, the safety in hemodialysis patients has not been established. A 76-year-old man was diagnosed with NSCLC with EGFR deletion mutation in exon 19. After treatment failure with first- and second-generation EGFR tyrosine kinase inhibitors, a T790M mutation was revealed by liquid biopsy. Hemodialysis was started three times a week because chronic renal failure worsened during treatment. Although the subsequent administration of osimertinib (80 mg, daily), resulted in a tumor shrinkage and a gradual increase in the plasma concentration of osimertinib, which resulted in grade 3 general fatigue. Reducing the dosage of osimertinib decreased its plasma concentration, leading to an improvement in his adverse event. Subsequently, with by adjusting the dosage while periodically measuring the plasma concentration of osimertinib, a stable therapeutic effect was sustained over the long term with no symptoms. Periodic plasma concentration measurements may be indispensable for successful treatment with osimertinib in hemodialysis patients.

奥希替尼（osimertinib）是治疗表皮生长因子受体（epidermal growth factor receptor, EGFR）突变阳性非小细胞肺癌（non-small cell lung cancer, NSCLC）的关键药物，但目前其在血液透析患者中的安全性尚未明确。一名76岁男性被确诊为携带19号外显子EGFR缺失突变的NSCLC患者。在接受第一代、第二代EGFR酪氨酸激酶抑制剂治疗失败后，液体活检检出其存在T790M突变。治疗期间患者慢性肾衰竭病情恶化，遂开始每周三次血液透析治疗。后续予以奥希替尼80mg每日一次给药，患者肿瘤出现缩小，但奥希替尼血浆浓度逐渐升高，引发3级全身乏力。减少奥希替尼给药剂量后，其血浆浓度下降，不良反应得到改善。后续通过定期监测奥希替尼血浆浓度调整给药剂量，患者长期维持稳定的治疗效果，且未再出现相关不良反应。定期监测奥希替尼血浆浓度，或为血液透析患者成功应用奥希替尼治疗的必要手段。