The goal of this Phase 1 clinical study is test tumor infiltrating lymphocytes (known as C-TIL051) with NKTR-255 and anti-PD1 therapy for subjects with refractory non-small cell lung cancer. The purpose of this study is to: 1. Test the safety and ability for subjects to tolerate the TIL therapy 2. Measure to see how the NSCLC responds to the TIL therapy Participants will be asked to: * Provide a tumor sample prior to the start of any treatment which will be used to make the C-TIL051. * Receive standard of care treatment until their lung cancer no longer responds * When necessary, the C-TIL051 will be manufactured by the sponsor and sent back to the site * Subject will then receive chemotherapy (called lymphodepletion) for 3 days followed by 2 days of rest * C-TIL051 will then be infused on day 0 followed by NKTR-255 (IL-15) about 12 to 24 hours later * Pembrolizumab will be administered every 3 weeks for up to 2 years NKTR-255 is a novel polymer-conjugated human IL-15 receptor agonist molecule designed to increase the proliferation and survival of memory CD8+ T cells and enhance the formation of long-term immunological memory which may lead to sustained anti-cancer immune response. The combination of NKTR 255 and TIL's could improve proliferation and persistence of cellular therapies leading to enhanced anti-tumor activity.