1216P - Effectiveness of osimertinib plus chemotherapy and avastin for EGFR-mutated advanced non-small cell lung cancer with brain metastases

Background

Previous studies suggested that the addition of bevacizumab (7. 5/15 mg/kg) tends to have PFS benefit for patients with asymptomatic CNS metastases. Therefore, whether osimertinib plus bevacizumab (15 mg/kg) could benefit those patients with multiple BMs remains undetermined, especially for those with edema.

Methods

The study was expected to enroll 26 patients diagnosed with EGFR-mutant NSCLC and brain metastases who received osimertinib (80mg QD) plus pemetrexed (500mg/m²), cisplatin (75mg/m²) and bevacizumab (15mg/kg) for 6 cycles, then matained with osimertinib/bevacizumab (15mg/kg), and not received radiotherapy. The primary endpoint was intracranial objective response rate (iORR), the secondary endpoint was the reduction of edema index(EI). Treatment was continued until disease progression and the tumor response was determined according to the Response Evaluation Criteria in Solid Tumors (RECIST) Version 1.1. EI was calculated according to Chinese Consensus Guidelines for Brain Edema Therapy. The toxicity was determined according to CTCAE 4.0.

Results

From February 2018 to January 2021, 26 patients enrolled showed in the table. All the patients were evaluable and showed partial response (PR) when make efficacy evaluation at the first time. The average reduction of the intracranial target lesions is 48.8%, ranged from 33% of Pt12 to 72% of Pt24. The average edema index (EI) reduction is of 3.49, 6 patients had no edema after therapy evaluated at the first time, Pt2 reduced from severe edema to moderate edema, and Pt20 reduced from moderate edema to mild edema. The toxicities associated with this protocols were manageable. Only 1 patient was 3/4-grade diarrhea and 3 patients was 3/4-grade lymphopenia.

Conclusions

Osimertinib in combination with chemotherapy and Bevacizumab exhibits superior activity and generally manageable toxicities for the EGFR-mutated advanced NSCLC patients with brain metastases, and also for the patients with concurrent edema. It may provide a new and effective therapy strategy for them, but large sample and additional clinical trials are also needed.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest. Table: 1216P