A multicenter, real-world study analysis: pembrolizumab changes treatment strategy for the patient with recurrent/metastatic head and neck squamous cell carcinoma.

Anti-PD-1/PD-L1 has made breakthrough progress in the treatment of recurrent and metastatic head and neck squamous cell carcinoma (R/M HNSCC). However, the Asian population in KEYNOTE-048 only accounts for 13.2% of the total population, and there is a lack of data on the mainland Chinese population. This multi-center trial (ChiCTR2400090060) evaluated the efficacy and safety of pembrolizumab in patients with R/M HNSCC. Between July 2020 and January 2024, 291 patients who received pembrolizumab-based therapy were enrolled from 20 hospitals across China. All patients were divided into two cohort: cohort 1 included patients unable surgery or radiotherapy (RT), who received first-line treatment of pembolizumab-based, and cohort 2 included patients eligible for surgery or RT, who received pembrolizumab-based treatment with or without local therapy. The primary endpoint was overall survival (OS), while secondary endpoints included time of pembrolizumab treatment (TOPT), immune-related adverse events (irAEs), and best overall response (BOR). With a median follow-up of 18.5 months, the mOS was not reached, with a 18mo-OS rate was 55.8%. The mOS for cohort 1 was 21.2 months. Interestingly, mOS for cohort 2 was not reached. Patients who received local therapy had a significantly improvement on 18mo-OS rate compared to those who did not (86.1% vs. 65.8%, p=0.021). A total of 24.7% of patients experienced irAEs. The study was the first report that the patient who was eligible for local treatment had a benefit from pembrolizumab, especially the OS was significantly improved for pembrolizumab followed by surgery or RT.