CNPGUT2020ANTIPD1

Several antibodies targeting programmed cell death protein-1 (PD-1) have been reported safety profiles and promising antitumor activities in patients with nasopharyngeal carcinoma (NPC). However, only a small subset of patients benefits from the anti-PD-1 monotherapy, and the factors that affect the response need further study. This study aims to investigate multiple impact factors by analyzing the tumor, blood, and fecal samples of 57 NPC patients that accept Nivolumab or Camrelizumab treatment. The whole exon sequencing (WES) data was obtained to analyzed the tumor mutation burden (TMB). We observed that high TMB combined with heterozygosity at human leukocyte antigen class I (HLA-I) loci is associated with improved clinical outcomes. The plasma EBV DNA loads were quantified by quantitative polymerase chain reaction for blood specimens. In agreement with previous studies, we find the patients with higher plasma EBV DNA load showed worse progression-free survival. More importantly, we examined the patients' gut microbiome composition by metagenomic shotgun sequencing and identified a high abundance of Clostridiales bacterium and Blautia obeum in non-responders. This study provides insight into the influence of multiple genetic and environmental factors on the anti-PD-1 immunotherapy in NPC patients.