Phase Ib Study of Osimertinib Plus Ramucirumab in Japanese Lung Cancer Patients With EGFR Mutation

Background/aim To explore the safety of osimertinib plus ramucirumab in patients with EGFR-mutated lung adenocarcinoma. Patients and methods Six advanced lung adenocarcinoma patients with EGFR mutation were treated with osimertinib 80 mg/day plus ramucirumab 10 mg/kg, every two weeks. Defined dose-limiting toxicity (DLT) was assessed within the first two treatment cycles. Results Of those enrolled, five patients had both EGFR exon 20 T790M mutation and sensitizing mutation. DLT was observed in one patient (grade 3 appetite loss). During the entire period, no other severe adverse event was observed. Five patients showed partial response and one disease progression. Median progression-free survival for patients with EGFR T790M was 9.2 months. In an exploratory analysis, changes of cell-free DNA at 2 weeks predicted radiological tumor responses. Conclusion The safety results of osimertinib plus ramucirumab in Japanese lung adenocarcinoma patients with EGFR mutation will lead to further efficacy investigation.