Keychain 006: This phase 3 trial is comparing the effectiveness of using either two targeted therapies (pembrolizumab and olaparib), or one targeted therapy (pembrolizumab) with a chemotherapy (pemetrexed) for the treatment of metastatic Non-Small-Cell Lung CancerA Phase 3 Study of Pembrolizumab in Combination With Pemetrexed/Platinum (Carboplatin or Cisplatin) Followed by Pembrolizumab and Maintenance Olaparib vs Maintenance Pemetrexed in the First-Line Treatment of Participants With Metastatic Nonsquamous Non-Small-Cell Lung Cancer

Exclusion

1. Has predominantly squamous cell histology NSCLC.
2. Has a known additional malignancy that is progressing or has progressed within the past 3 years requiring active treatment.
3. Has known active central nervous system (CNS) metastases and/or carcinomatous meningitis.
4. Has a severe hypersensitivity (≥Grade 3) to pembrolizumab and/or any of its excipients.
5. Has a known hypersensitivity to any components or excipients of cisplatin, carboplatin, pemetrexed, or olaparib.
6. Has an active autoimmune disease that has required systemic treatment in past 2 years.
7. Has a diagnosis of immunodeficiency or is receiving chronic systemic steroid therapy.
8. Has a known history of human immunodeficiency virus (HIV) infection, a known history of hepatitis B infection, or known active hepatitis C virus infection.
9. Has interstitial lung disease, or history of pneumonitis requiring systemic steroids for treatment.
10. Has received prior therapy with olaparib or with any other polyadenosine 5' diphosphoribose (polyADP ribose) polymerization (PARP) inhibitor.
11. Has received prior therapy with an agent directed to programmed cell death ligand 1 (PD-L1), anti PD-L2, or directed to a stimulatory or co-inhibitory T-cell receptor (e.g., cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), OX-40, CD137).
12. Has myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML) or with features suggestive of MDS/AML.
13. Has not completed palliative radiotherapy within 7 days of the first dose. Participants must have recovered from all radiation-related toxicities and not require corticosteroids.