Pembrolizumab for Advanced NSCLC and PS 2-3

Patients will be treated with the standard dose of pembrolizumab for the first 12 weeks of the study. After week 12 assessments, patients without objective progression of disease are eligible to transition to Q6W dosing of pembrolizumab 400mg IV. Patients will be offered this schedule, also an FDA-approved option, at the discretion of the treating physician, based on tolerability of the q3week regimen and clinician assessment of need for closer follow up intervals. Pembrolizumab will be continued until disease progression, unacceptable toxicity, withdrawal of consent, or death.