A Study of Amivantamab and Lazertinib in Combination With Platinum-Based Chemotherapy Compared With Platinum-Based Chemotherapy in Patients With Epidermal Growth Factor Receptor (EGFR)-Mutated Locally Advanced or Metastatic Non- Small Cell Lung Cancer After Osimertinib Failure

The purpose of this study is to assess the efficacy of adding lazertinib to amivantamab, carboplatin, and pemetrexed (LACP/ACP-L dosing strategies) and amivantamab, carboplatin and pemetrexed (ACP) compared with carboplatin and pemetrexed (CP) in participants with locally advanced or metastatic epidermal growth factor receptor (EGFR) Exon 19del or Exon 21 L858R substitution non-small cell lung cancer (NSCLC) after osimertinib failure. The purpose of the extension cohort is to further describe the safety and efficacy for the ACP-L dosing schedule versus ACP with additional data. After completion of the primary analysis, the study may eventually transition to an open-label extension (OLE) or long-term extension (LTE) phase during which participants will have the option to continue their assigned treatment.

Inclusion Criteria: * Participant must have at least 1 measurable lesion, according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, that has not been previously irradiated * Participant must have histologically or cytologically confirmed, locally advanced or metastatic, non-squamous non-small cell lung cancer (NSCLC), characterized at or after the time of locally advanced or metastatic disease diagnosis by either epidermal growth factor receptor (EGFR) Exon 19del or Exon 21 L858R mutation * A participant with a history of brain metastases must have had all lesions treated as clinically indicated (that is, no current indication for further definitive local therapy). Any definitive local therapy to brain metastases must have been completed at least 14 days prior to randomization and the participant can be receiving no greater than10 milligrams (mg) prednisone or equivalent daily for the treatment of intracranial disease * Participant must have Eastern Cooperative Oncology Group (ECOG) status of 0 or 1 * Any toxicities from prior systemic anticancer therapy must have resolved to National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) Version 5.0 Grade 1 or baseline level (except for alopecia \[any grade\], Grade \<= 2 peripheral neuropathy, or Grade \<= 2 hypothyroidism stable on hormone replacement) * A participant of childbearing potential must have a negative serum pregnancy test at screening and within 72 hours of the first dose of study treatment and must agree to further serum or urine pregnancy tests during the study * Participant must have progressed on or after osimertinib monotherapy as the most recent line of treatment. Osimertinib must have been administered as either the first-line treatment for locally advanced or metastatic disease or in the second- line setting after prior treatment with first- or second-generation EGFR tyrosine kinase inhibitor (TKI) as a monotherapy. Participants who received either neoadjuvant and/or adjuvant treatment of any type are eligible if progression to locally advanced or metastatic disease occurred at least 12 months after the last dose of such therapy and then the participant progressed on or after osimertinib in the locally advanced or metastatic setting. Treatment with osimertinib must be discontinued at least 8 days (4 half-lives) prior to randomization (that is last dose no later than Day -8) Exclusion Criteria: * Participant received radiotherapy for palliative treatment of NSCLC less than 14 days prior to randomization * Participant with symptomatic or progressive brain metastases * Participant has history of or current evidence of leptomeningeal disease, or participant has spinal cord compression not definitively treated with surgery or radiation * Participant has known small cell transformation * Participant has a medical history of interstitial lung disease (ILD), including drug-induced ILD or radiation pneumonitis * Participant has a history of clinically significant cardiovascular disease including, but not limited to diagnosis of deep vein thrombosis or pulmonary embolism within 4 weeks prior to randomization; myocardial infarction; unstable angina; stroke; transient ischemic attack; coronary/peripheral artery bypass graft; or acute coronary syndrome. Participant has a significant genetic predisposition to venous thromboembolic events. Participant has a prior history of venous thromboembolic events and is not on appropriate therapeutic anticoagulation as per National Comprehensive Cancer Network or local guidelines