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

Inclusion Criteria: 1. Provide written informed consent. 2. 18 years old or older. 3. Eastern Cooperative Oncology Group (ECOG) performance status of 0-1. 4. Unresectable, metastatic or locally advanced EGFR-mutated NSCLC. 5. Prior treatment with osimertinib as first or second line, as single agent or in combination with chemotherapy, in the metastatic or locally advanced setting. Exclusion Criteria: 1. Subject's cancer has a known oncogenic driver alteration other than EGFR. 2. Known EGFR mutations that cause resistance to osimertinib 3. Known human epidermal growth factor receptor 2 (HER2) overexpression 4. Any contraindications to treatment with osimertinib