Pembrolizumab in Elderly Patients With Advanced Lung Cancer

Inclusion Criteria: 1. Patients with histological or cytological documented stage III B or IV squamous and non-squamous non-small-cell lung cancer previously untreated. 2. Epidermal Growth Factor receptor (EGFR) and Anaplastic lymphoma kinase (ALK) have to be wild-type. 3. The subject must be willing and able to provide written informed consent/assent for the trial. 4. Patients must be aged more than 70 years, on day of signing informed consent. 5. Measurable disease (at least 1 lesion) based on RECIST criteria v1.1. Patients will not be eligible if this lesion was irradiated before inclusion. 6. Be willing to provide tissue from a newly obtained core or excision biopsy of a tumor lesion. Newly-obtained is defined as a specimen obtained up to 6 weeks (42 days) prior to initiation of treatment on Day 1. Subjects for whom newly-obtained samples cannot be provided (e.g. inaccessible or subject safety concern) may submit an archived specimen only upon agreement from the Sponsor. 7. PD-L1 expression ≥ 1% 8. Have a performance status of 0 or 1 on the Eastern Cooperative Oncology Group Performance Scale. 9. Screening laboratory values must meet the following criteria (Table 1, see protocol), all screening laboratory tests should be performed within 8 days of treatment initiation. 10. Male subjects of childbearing potential must agree to use an adequate method of contraception, starting with the first dose of study therapy through 120 days after the last dose of study therapy. Exclusion Criteria: 1. Is currently participating and receiving study therapy or has participated in a study of an investigational agent and received study therapy or used an investigational device within 4 weeks of the first dose of treatment. 2. Has a diagnosis of immunodeficiency or is receiving systemic steroid therapy at a dose over 10 mg of prednisone or equivalent, or any other form of immunosuppressive therapy within 7 days prior to the first dose of trial treatment. 3. Has a known history of active Tuberculosis Bacillus 4. Hypersensitivity to Pembrolizumab or any of its excipients. 5. Has had any prior anti-cancer therapy for his or her metastatic NSCLC. In the case of patients who have progressed to a metastatic stage after having been treated for early stage NSCLC, chemotherapy or radiation therapy as part of this previous treatment is allowed, provided they have been completed more than three months ago. Patients who received adjuvant or neoadjuvant treatment or both for early stages will be eligible for this trial. All adverse events related to these previous treatments must have recovered (i.e., ≤ Grade 1 or at baseline). 6. Has had any previous malignancy (except non melanoma skin cancer, and cancer in situ of: bladder, gastric, colon, cervical/dysplasia, melanoma, breast), unless a complete remission was achieved at least 2 years prior to study entry and no additional therapy is required or anticipated to be required during the study period. 7. Has known active central nervous system (CNS) metastases and/or carcinomatous meningitis. Subjects with previously treated brain metastases may participate if they are stable (without evidence of progression by imaging for at least four weeks prior to the first dose of trial treatment and any neurologic symptoms have returned to baseline), have no evidence of new or enlarging brain metastases, and are not using steroids at a dose over 10 mg of prednisone or equivalent, for at least 7 days prior to trial treatment. This exception does not include carcinomatous meningitis which is excluded regardless of clinical stability. 8. Has active autoimmune disease that has required systemic treatment in the past 2 years (i.e. with use of disease modifying agents, corticosteroids or immunosuppressive drugs). Replacement therapy (eg., thyroxin, insulin, or physiologic corticosteroid replacement therapy for adrenal or pituitary insufficiency, etc.) is not considered a form of systemic treatment. 9. Has a history of (non-infectious) pneumonitis that required steroids or current pneumonitis. 10. Has an active infection requiring systemic therapy. 11. Has a history or current evidence of any condition, therapy, or laboratory abnormality that might confound the results of the trial, interfere with the subject's participation for the full duration of the trial, or is not in the best interest of the subject to participate, in the opinion of the treating investigator. 12. Has known psychiatric or substance abuse disorders that would interfere with cooperation with the requirements of the trial. 13. Has any geriatric exclusion criteria: * advanced dementia (GDS ranking \>6) * moderate or severe functional dependence (Barthel Index \< 35) * Life expectancy less than one year, due to co-morbidities other than lung cancer. 14. Has a known history of Human Immunodeficiency Virus (HIV) (HIV 1/2 antibodies). 15. Has known active Hepatitis B (e.g., HBsAg reactive) or Hepatitis C (e.g., Hepatitis C Virus RNA \[qualitative\] is detected). 16. Has received a live vaccine within 30 days of planned start of study therapy. Note: Seasonal influenza vaccines for injection are generally inactivated flu vaccines and are allowed; however intranasal influenza vaccines (e.g., Flu-Mist®) are live attenuated vaccines, and are not allowed. 17. Evidence of interstitial lung disease.