Inclusion Criteria:

          -  Histologically confirmed diagnosis of non-small cell lung carcinoma with tumour PDL-1
             TPS≥50% by 22C3 pharmDx immunohistochemistry. Patients must have EGFR wild-type,
             ALK-rearrangement negative metastatic or advanced NSCLC (stage IV or incurable stage
             III). Patients with neuroendocrine (carcinoid) carcinoma, small cell or mixed small
             cell and non-small cell carcinoma are not eligible.

          -  Must agree to use methods to prevent pregnancy as agreed upon between the investigator
             and the participant for at least 120 days after the last dose of study treatment.

          -  The participant provides written informed consent for the trial.

          -  Have measurable disease.

          -  Provide archival tumor tissue sample for KRAS/BRAF/STK11 mutation analysis or newly
             obtained core or excisional biopsy of a tumor lesion not previously irradiated.

          -  Have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1.

          -  Have a life expectancy of greater than 3 months.

          -  Be able to swallow and retain oral medication and not have any clinically significant
             gastrointestinal abnormalities that may alter absorption such as malabsorption
             syndrome or major resection of the stomach or bowels.

          -  Have adequate organ function.

        Exclusion Criteria:

          -  Female with positive urine pregnancy test.

          -  Has received prior therapy with an anti-PD-1, anti-PD-L1, or anti-PD-L2 agent or with
             an agent directed to another stimulatory or co-inhibitory T-cell receptor, or a prior
             MEK inhibitor.

          -  Has received prior systemic anti-cancer therapy including investigational agents
             within 4 weeks prior to registration, excluding supportive medications such as
             bisphosphonates.

          -  Has received prior radiotherapy within 2 weeks of start of study treatment.
             Participants must have recovered from all radiation-related toxicities, not require
             corticosteroids, and not have had radiation pneumonitis. A 1-week washout is permitted
             for palliative radiation (≤2 weeks of radiotherapy) to non-central nervous system
             disease.

          -  Has received a live vaccine within 30 days prior to the first dose of study drug.

          -  Is currently participating in or has participated in a study of an investigational
             agent or has used an investigational device within 4 weeks prior to the first dose of
             study treatment.

          -  Has a diagnosis of immunodeficiency or is receiving chronic systemic steroid therapy
             (in dosing exceeding 10 mg daily of prednisone equivalent) or any other form of
             immunosuppressive therapy within 7 days prior to the first dose of study drug.

          -  Has a known additional malignancy that is progressing or has required active treatment
             within the past year.

          -  Has known active central nervous system metastases and/or carcinomatous meningitis.
             Participants with previously treated brain metastases may participate provided they
             are radiologically stable, clinically stable and without requirement of steroid
             treatment for at least 14 days prior to first dose of study treatment.

          -  Has severe hypersensitivity (≥Grade 3) to pembrolizumab and/or any of its excipients,
             or history of allergic reactions attributed to compounds of similar composition to
             binimetinib.

          -  Has active autoimmune disease that has required systemic treatment in the past 2
             years.

          -  Has a history of (non-infectious) pneumonitis that required steroids or has current
             pneumonitis.

          -  Has an active infection requiring systemic therapy.

          -  Has a known history of Human Immunodeficiency Virus.

          -  Has a known history of Hepatitis B or known active Hepatitis C virus infection.

          -  Has a known history of active (untreated) bacillus tuberculosis (TB).

          -  Has a history or current evidence/risk of retinal vein occlusion (RVO) or predisposing
             factors to RVO

          -  Has a history of retinal degenerative disease.

          -  Has a history of Gilbert's syndrome

          -  Has any factors that increase the risk of QTc prolongation or risk of arrhythmic
             events or baseline QTcB interval >480 msec

          -  Has a history of acute coronary syndromes, coronary artery bypass grafting,
             angioplasty, or stenting within the past 6 months prior to screening or cardiac
             metastases.

          -  Has history or evidence of current clinically significant uncontrolled arrhythmias.

          -  Has a history or evidence of current ≥Class II congestive heart failure as defined by
             New York Heart Association (NYHA).

          -  Has an intra-cardiac defibrillator or permanent pacemaker.

          -  Has treatment-refractory hypertension defined as a systolic blood pressure >140 mmHg
             and/or diastolic >90 mmHg which cannot be controlled by anti-hypertensive therapy.

          -  Has a history of neuromuscular disorders associated with elevated creatine
             phosphokinase (CK).

          -  Is planning to embark on a new strenuous exercise regimen after the first dose of
             study treatment.

          -  Has a history or current evidence of any condition, therapy, or laboratory abnormality
             that might confound the results of the study, interfere with the subject's
             participation for the full duration of the study, or is not in the best interest of
             the subject to participate, in the opinion of the treating investigator.

          -  Has known psychiatric or substance abuse disorders that would interfere with
             cooperation with the requirements of the trial.

          -  Is pregnant or breastfeeding, or expecting to conceive or father children within the
             projected duration of the study, starting with the screening visit through 120 days
             after the last dose of trial treatment.