Renal dysfunction during osimertinib treatment in patients with non–small cell lung cancer positive for EGFR mutations

Background: Osimertinib is a standard treatment for non–small cell lung cancer (NSCLC) positive for EGFR activating mutations. Although renal dysfunction associated with osimertinib treatment is reported to be rare, detailed information on this adverse effect is needed because cytotoxic drugs such as pemetrexed are also widely administered for NSCLC but cannot be used in individuals with renal dysfunction. Methods: We retrospectively collected clinical data including the serum creatinine concentration and estimated glomerular filtration rate (eGFR) during osimertinib treatment for 130 NSCLC patients. Results: Serum creatinine and eGFR worsened gradually during osimertinib treatment, with the median value of creatinine at the point of greatest deterioration differing significantly from that at baseline (0.93 versus 0.72 mg/dL, P < 0.01). Seventy patients (54 %) experienced worsening of the CTCAE grade for creatinine increased, with the frequency of patients with grade 1 or 2 being increased significantly (P < 0.01) at the point of greatest deterioration relative to baseline (grade 1, 46.9 % versus 14.6 %; grade 2, 14.6 % versus 0.8 %, respectively). A higher serum creatinine level at baseline was a significant risk factor for worsening of the CTCAE grade (odds ratio of 1.66, P < 0.001). The median serum creatinine and eGFR at 4 weeks after osimertinib discontinuation had improved to levels similar to those for baseline. Conclusions: Renal dysfunction occurred frequently during osimertinib treatment but was ameliorated after drug discontinuation, suggesting that, although renal function should be carefully monitored, its impairment is not likely to affect subsequent chemotherapy in most patients.