Osimertinib in EGFR-positive non-small cell lung cancer spread to the brain or the layers surrounding the brain.

This trial was carried out to examine the effectiveness of osimertinib (Tagrisso) in non-small cell lung cancer (NSCLC) that has spread to the brain of the layers of the brain (meninges). The authors concluded that osimertinib showed improved survival and had a good response rate in these patients.

NSCLC is responsible for around 85% of all lung cancer diagnoses. While there are many treatment options such as chemotherapy, radiation therapy, and surgical removal of tumors, NSCLC that has spread remains difficult to treat. Some NSCLCs grow in response to EGFR, a protein that helps cancer cells grow and spread faster. 

Osimertinib works by blocking signals to EGFR. This helps shink cancer cells and stops them from multiplying. Osimertinib 80mg has shown effectiveness in treating NSCLC that has spread to the central nervous system (spine and brain metastases). However, the safety and effectiveness of osimertinib 160mg in patients with brain metastases (BM) or leptomeningeal metastases (LM; cancer spread in the tissue layer covering the brain and spine) remain under investigation.

There were 80 patients with NSCLC and BM  (40 patients) or LM (40 patients) involved in this trial. All patients had EGFR mutations and had been previously treated with an EGFR inhibitor drug, including osimertinib 80mg. All patients received osimertinib 160mg in this study. The average follow-up was 10.1 months in the BM group and 9.6 months in the LM group. 

In the BM group, the response rate was 55%. 77.5% of the patients had disease control (the cancer was not progressing). The average time without disease progression in the BM group was 7.6 months and the average overall survival was 16.9 months.

In the LM group, the response rate was 27.5%, while 92.5% had disease control. The average time without disease progression was 8 months and the average overall survival was 13.3 months. 

The authors concluded that 160mg of osimertinib is a safe and effective option for patients with NSCLC that has spread to BM or LM after previous EGFR inhibitor therapy. 

This study was sponsored by Astra Zeneca, the manufacturers of osimertinib. This study had a small number of participants and a short follow-up period. Also, there was no control group for comparison. Further studies are needed.