PDCD1 and non-small cell lung carcinoma: Additionally, the role of a combination of PD-1 inhibitors and CTLA-4 inhibitors in advanced NSCLC treatment are currently being studied in three phase 2 trials and eight phase 3 trials (clinicaltrial.gov ID: NCT03091491; NCT02659059; NCT03057106; NCT03215706; NCT03048136; NCT02477826; NCT02998528; NCT02453282; NCT02542293; NCT02352948; NCT03164616).