Both Part A and B are randomized, double-blind, placebo-controlled.

Experimental: Part A: Olomorasib + Pembrolizumab
Participants will receive olomorasib administered orally in combination with pembrolizumab intravenously (IV) for up to 1 year followed by olomorasib alone for up to 3 years of total treatment.

Placebo Comparator: Part A: Placebo + Pembrolizumab
Participants will receive placebo administered orally in combination with pembrolizumab administered IV for up to 1 year followed by placebo alone for up to 3 years of total treatment.

Experimental: Part B: Olomorasib + Durvalumab
Participants will receive olomorasib administered orally in combination with durvalumab administered IV for up to 1 year followed by olomorasib alone for up to 3 years of total treatment.

Placebo Comparator: Part B: Placebo + Durvalumab
Participants will receive placebo administered orally in combination with durvalumab administered IV for up to 1 year followed by placebo alone for up to 3 years of total treatment.

Part A: Disease-Free Survival (DFS) by Investigator Assessment
Part B: Progression-Free Survival (PFS)
Part A & B: Overall Survival (OS)

• Histological or cytological confirmation of NSCLC.

  • Part A
    1. Clinical Stage II-IIIB (N2) treated with presurgical chemoimmunotherapy, with residual tumor present at time of surgery. Patients with a pathologic complete response are not eligible.
    2. Pathologic Stage II-IIIB (N2) NSCLC treated with initial upfront resection.
  • Part B - Clinical Stage III, unresectable NSCLC, without progression on concurrent platinum-based chemoradiotherapy.

• Must have disease with evidence of KRAS G12C mutation.

• Must have known programmed death-ligand 1 (PD-L1) expression

• Must have an ECOG performance status of 0 or 1.

• Able to swallow oral medication.

• Must have adequate laboratory parameters.

• Contraceptive use should be consistent with local regulations for those participating in clinical studies.

• Women of childbearing potential must

  • Have a negative pregnancy test.
  • Not be breastfeeding during treatment

• Have known changes in the EGFR or ALK genes.
• Have another type of cancer that is progressing or required active treatment within the past 3 years before screening.
• Have an active autoimmune disease that required systemic treatment in the past 2 years. Endocrine replacement therapy is allowed.
• Had any immune-related side effect or allergic reaction (Grade 3 or higher) from a previous immunotherapy medicine, or any immune-related side effect greater than Grade 1 that has not resolved. This does not apply for people with hormone-related diseases who are now on stable hormone replacement therapy.