Key Inclusion Criteria: - Are at least 18 years old (or old enough to legally make their own treatment decisions, according to local laws). - Have advanced NSCLC or metastatic NSCLC (NSCLC that started in the lungs and then spread to other parts of the body) with the KRAS G12C mutation. - Have had previous treatment with 1) chemotherapy that included a drug called cisplatin or a drug called carboplatin and 2) a type of drug called an immune checkpoint inhibitor. - Have recovered from their prior treatment and blood tests are within a safe range. Key Exclusion Criteria: - Have had previous treatment with a drug that targets KRAS G12C. - Have cancer that can potentially be removed with surgery. - Patients with brain lesions are not eligible if 1) any untreated brain lesions are > 2.0 cm in size 2) any brainstem lesions are present 3) ongoing steroid dosing >10 mg daily prednisone (or equivalent) and 4) poorly controlled (> 1/week) generalized or complex partial seizures or neurologic progression/instability due to brain lesions. - Have certain medical conditions or need to take certain medications that, in the opinion of a trial doctor, could make it unsafe for them to participate or difficult to complete the trial assessments, or are pregnant.