Chemo-immunotherapy, Hypo-fractionated RT and Maintenance Immunotherapy for Stage III NSCLC.

The study hypothesis is that the new regimen tested in this study will be safe and effective by: 1. anticipating the use of durvalumab, together with chemotherapy (higher efficacy) 2. harnessing response to induction chemo-durvalumab (which is expected to be significant) to be able to reduce radiotherapy dose without reducing tumor control probability 3. reducing radiation-induced immunosuppression 4. reducing radiation-induced late morbidity, this aspect is important when considering that this regimen is expected to be able to cure a proportion of patients (long-term survivors) In this phase II study, the investigators will evaluate the combination of induction chemotherapy plus durvalumab followed by reduced-dose hypo-fractionated thoracic RT (concurrent with durvalumab) and durvalumab maintenance for stage 3 unresectable NSCLC patients candidate to sequential chemo-RT.