A Study of Lazertinib as Monotherapy or in Combination With Amivantamab in Participants With Advanced Non-small Cell Lung Cancer

Open to people ages 18 years and up

• Histologically or cytologically confirmed non-small cell lung cancer (NSCLC) with previously epidermal growth factor receptor (EGFR) mutation (identified locally in a Clinical Laboratory Improvement Amendments [CLIA]-certified laboratory [or equivalent]) that is metastatic or unresectable, and have progressed after standard of care front-line therapy, and exhausted available options with targeted therapy. A participant who has refused all other currently available therapeutic options is allowed to enroll. For the Phase 1b Lazertinib, Amivantamab and Platinum-doublet

Chemotherapy (LACP) combination cohort: histologically or cytologically confirmed advanced or metastatic EGFR-mutated NSCLC who have progressed on or after an EGFR-TKI as the most recent line of treatment with a maximum of 3 prior lines of therapy in the metastatic setting allowed. Phase 1b expansion Cohort A, B and C: For all expansion cohorts, the EGFR mutation must have been previously histologically or cytologically characterized, as performed by a CLIA-certified (US sites) or an accredited (outside of US) local laboratory, with a copy of the mutation analysis being submitted during screening. Expansion Cohort A: Participant must have advanced or metastatic EGFR-mutated non-small cell lung cancer (NSCLC) that has progressed on prior treatment with osimertinib in the first or second line, followed by progression on a platinum-based chemotherapy regimen as the last line of therapy prior to study enrollment. Prior use of first or second generation EGFR tyrosine kinase inhibitor (TKI) is allowed if administered prior to osimertinib. Expansion Cohort B: Participant must have previously treated, advanced or metastatic NSCLC with documented primary EGFR Exon 20ins activating mutation. Participants should have been treated with standard of care, platinum-based chemotherapy regimens, but may have treated with approved EGFR TKI, investigational EGFR, or immunotherapy agents if refusing front line platinum-based chemotherapy standard of care. Up to 3 lines of prior systemic anti-cancer treatment are allowed. Expansion Cohort C: Participant must have advanced or metastatic NSCLC characterized by an uncommon activating mutation Additional uncommon EGFR mutations/alterations, beyond those listed above, may be considered for enrollment after agreement with the medical monitor. Participants may be treatment naïve or have been treated with one prior line of therapy which must be a first or second generation TKI (that is gefitinib, erlotinib, afatinib) in the most recent line of therapy. Prior chemotherapy is allowed if administered prior to EGFR TKI therapy, or as the only systemic anti-cancer therapy prior to study enrollment. Up to 2 lines of prior systemic anti-cancer treatment are allowed

• Evaluable disease
• Eastern Cooperative Oncology Group (ECOG) performance status grade of 0 or 1
• Participants must meet the study protocol defined laboratory criteria without having a history of red blood cell transfusion, platelet transfusion, or granulocyte-colony stimulating factor support within 7 days prior to the date of the test
• A woman of childbearing potential: Must have a negative serum beta human chorionic gonadotropin at screening; Must agree not to breast-feed during the study and for 6 months after the last dose of study intervention. (Enrollment is not allowed even if a woman who is breast-feeding stops breast-feeding); Must agree not to donate eggs (ova, oocytes) for the purposes of assisted reproduction during the study and for 6 months after receiving the last dose of study intervention

• Participant has an uncontrolled illness, including but not limited uncontrolled diabetes, ongoing or active infection (includes infection requiring treatment with antimicrobial therapy [participants will be required to complete antibiotics week prior to study treatment] or diagnosed or suspected viral infection); active bleeding diathesis; Impaired oxygenation requiring continuous oxygen supplementation; Refractory nausea and vomiting, chronic gastrointestinal diseases, inability to swallow the formulated product, or previous significant bowel resection that would preclude adequate absorption of study treatment; or psychiatric illness or any other circumstances including (social circumstances) that would limit compliance with study requirements. Any ophthalmologic condition that is either clinically unstable or requires treatment
• Prior treatment with antiPD-1 or anti Programmed death-ligand 1 (PD-L1) antibody within 6 weeks of planned first dose of study intervention
• Untreated brain or other central nervous system (CNS) metastases whether symptomatic or asymptomatic. Participants who have completed definitive therapy, are not on steroids, and have a stable clinical status for at least 2 weeks prior to study treatment may be eligible for Phase 1b expansion cohorts. If brain metastases are diagnosed on Screening imaging, the participant may be enrolled, or rescreened for eligibility, after definitive treatment if above criteria are met
• Any Toxicities from prior anticancer therapy must have resolved to common terminology criteria for adverse events (CTCAE) version 5.0 Grade 1 or baseline level (except for alopecia [any grade], Grade <=2 peripheral neuropathy, and Grade <=2 hypothyroidism stable on hormone replacement therapy)
• Allergies, hypersensitivity, or intolerance to Lazertinib (both Phase 1 and Phase 1b) or their excipients. For the LACP combination cohort: participant has a contraindication for the use of carboplatin or pemetrexed (refer to local prescribing information for each agent). Participant has a history of hypersensitivity to, or cannot take, vitamin B12 or folic acid