Study of Immunotherapy (Sasanlimab) in Combination With Targeted Therapies in People With Advanced Non-small Cell Lung Cancer (NSCLC) (Landscape 1011 Study)

Inclusion Criteria Umbrella Phase 1b \& 2: * Histologically or cytologically confirmed locally advanced/metastatic (Stage IIIB-IV) NSCLC. * At least one measurable lesion per RECIST v1.1 at Screening. * ECOG Performance Status 0 or 1. * Resolved acute effects of any prior therapy to baseline severity or CTCAE Grade ≤1. * Adequate hepatic, renal, and bone marrow function. Additional Inclusion Criteria for Sub-Study A Phase 1b \&2: -BRAFV600E mutation in tumor tissue or plasma as determined by a local laboratory PCR or NGS assay and documented in a local pathology report. Additional Inclusion Criteria for Sub-Study A Phase 1b only: -Any line of therapy for locally advanced/metastatic NSCLC. Additional Inclusion Criteria for Sub-Study A Phase 2 only: -Previously untreated for locally advanced/metastatic NSCLC Additional Inclusion Criteria for Sub-Study B Phase 1b only:: -Any line of therapy for locally advanced/metastatic NSCLC. Additional Inclusion Criteria for Sub-Study B Phase 2 only: * Previously untreated for locally advanced/metastatic NSCLC (Arms B1 \& B2), or * One or 2 prior lines of therapy for advanced/metastatic NSCLC (Arm B3), including immune checkpoint inhibitor treatment + chemotherapy, and have progressed during or after that therapy. * PD-L1 TPS ≥1% Exclusion Criteria Umbrella Phase 1b \&2: * Active or prior autoimmune disease that might deteriorate when receiving an immunostimulatory agent. * Active non-infectious pneumonitis, pulmonary fibrosis, or known history of immune-mediated pneumonitis. * Active infection requiring systemic therapy. * Clinically significant cardiovascular disease. * Other malignancy within 2 years of first dose, with exceptions. * Symptomatic brain metastasis, with exceptions. Additional Exclusion Criteria for Sub-Study A Phase 1b\&2: * EGFR mutation, ALK fusion oncogene, or ROS1 rearrangement. * Prior treatment with any BRAF inhibitor or MEK inhibitor. Additional Exclusion Criteria for Sub-Study A Phase 2 only: -Prior therapy with anti-PD-1, anti-PD-L1, or anti-PD-L2 agents. Additional Exclusion Criteria for Sub-Study B Phase 1b\&2: -Documentation of any tumor-driving molecular alteration (eg, BRAF, EGFR, ALK) Additional Exclusion Criteria for Sub-Study B Phase 2 only: * Prior therapy with anti-PD-1, anti-PD-L1, or anti-PD-L2 agents.(Arms B1 \& B2) * Confirmed progressive disease on 1st or 2nd imaging tumor assessment after initiation of therapy for advanced/metastatic NSCLC.