PDCD1 and nasopharyngeal carcinoma: As reported in nasopharyngeal carcinoma, these studies have shown a possible difference in efficacy and in the safety profiles across different anti-PD-1-based regimens, in which the ORR was higher for pembrolizumab than for nivolumab (26.3% vs. 19.0%) as a second- or later-line therapy, whereas the ORR with the first-line nivolumab reached as high as 40% [17].