Reduced CT + Anti-PD-1 as First Line Tx in Vulnerable Older Adults w/Adv <50% PD-L1 Non-Small Cell Lung Cancer (NSCLC)

Inclusion Criteria:

* Histologically or cytologically confirmed diagnosis of non-small cell lung cancer (NSCLC) (either squamous or non- squamous)
* Stage IIIB, IIIC or IV disease OR have recurrent disease and not be candidates for curative treatment such as combined chemo-radiation
* No previous line of treatment in the recurrent or metastatic setting. Neoadjuvant or adjuvant treatment more than 6 months before enrollment is acceptable.
* Age 70 or meeting frailty definition or above at the date of signing informed consent
* Absence of driver mutations that have first line Food and Drug Administration (FDA) approved targeted therapy (biomarker testing is optional for squamous cell)
* PD-L1 tumor proportion score (TPS) of less than 50%
* Eastern Cooperative Oncology Group (ECOG) PS of 0-3
* Have measurable disease based on RECIST 1.1 as determined by the local site investigator/radiology assessment
* Absolute neutrophil count (ANC) ≥ 1,000/μL
* Platelets ≥ 75,000/μL
* Hemoglobin (Hgb) ≥ 8.0 g/dL (transfusion permitted)
* Total bilirubin ≤ 2 x institutional upper limit of normal (ULN)
* Aspartate amino transferase (AST)serum glutamic-oxaloacetic transaminase (SGOT) /alanine aminotransferase (ALT)serum glutamic-pyruvic transaminase (SGPT) ≤ 5.0 × institutional ULN
* Ability to understand and the willingness to sign a written informed consent document

Exclusion Criteria:

* Participants with life expectancy of less than 3 months at the time of enrollment
* Has active autoimmune disease that has required systemic treatment in past 2 years (ie, with use of disease modifying agents, or immunosuppressive drugs)
* Diagnosis of interstitial lung disease
* Creatinine clearance of \<30 mL/min
* Symptomatic, untreated central nervous system (CNS) disease or leptomeningeal disease. Patients with asymptomatic or treated CNS disease are eligible
* Required ongoing use of immunosuppressive medication, including steroids, with the following allowable exceptions:

  * Doses less than or equal to the equivalent of prednisone 10 mg daily
  * Short courses of steroids that are discontinued prior to enrollment
  * Inhaled, intranasal and/or topical steroids
  * Dexamethasone taper for treating vasogenic edema associated with CNS disease