Checkpoint inhibitors (CIs) are now standard of care for late-stage non-small-cell lung cancer (NSCLC); however, only a minority of patients treated with a CI show clinical benefit compared to platinum-based chemotherapy alone, regardless of programmed cell death ligand 1 (PD-L1) expression levels. We describe a case of durable tumor response and disease stabilization in a patient with advanced pretreated squamous NSCLC given a maintenance treatment comprised of nivolumab, docetaxel, and ramucirumab combined with the allogeneic cellular cancer vaccine viagenpumatucel-L over a period of 28 months. Our case suggests that combination strategies that serve to sensitize tumors to checkpoint inhibition, even in patients refractory to available treatment, may lead to improved efficacy.