Study of NXP900 With Osimertinib in Subjects With Advanced, EGFR-Mutated Non-Small Cell Lung Cancer

This study is testing a new drug called NXP900 used together with osimertinib (a standard targeted therapy) in people with advanced non-small cell lung cancer that has a specific mutation in the EGFR gene. **You may be eligible if...** - You are 18 or older - You have advanced, locally advanced, or metastatic non-small cell lung cancer with an EGFR mutation - You have previously been treated with osimertinib (alone or combined with chemotherapy) - You are in good physical condition (ECOG score 0 or 1) **You may NOT be eligible if...** - Your cancer has a different main driver mutation (other than EGFR) - You have a known EGFR mutation that causes resistance to osimertinib - You have HER2 overexpression - You have a medical condition that prevents you from safely taking osimertinib Talk to your doctor to see if this trial is right for you.