This study aimed to explore the efficacy and safety of sintilimab combined with induction chemotherapy (IC) in locally advanced head and neck squamous cell carcinoma (HNSCC) patients.

A total of 163 patients were prospectively enrolled; 98 patients received IC only, and 65 patients received IC with sintilimab. Following neoadjuvant therapy, patients either underwent surgery (31.9%) or chemoradiotherapy (68.1%). Objective response rate (ORR), progression free survival (PFS), overall survival (OS), and toxicities between the two groups were compared.

The ORR in the IC group was significantly lower than that in the IC with sintilimab group (68.4% vs 84.6%, P = 0.019). Grade 3 or higher acute toxicity occurred in 15 (15.3%) and 12 (18.5%) patients in the IC and IC with sintilimab groups, respectively. However, this difference was not significant (P = 0.596). After follow-up with a median time of 28.0 months, the IC group had a 2-year PFS rate of 27% (95%CI: 18-36%), whereas the IC with sintilimab group had a 2-year PFS rate of 44% (95%CI: 32-56%), and this difference was significant (P = 0.041). The 2-year OS rates in the IC and IC with sintilimab groups were 61% (95%CI: 52-70%) and 70% (95%CI: 60-80%), respectively, the difference was not significant (P = 0.681).

Addition of sintilimab to IC could provide longer PFS time than traditional chemotherapy regimen, without increasing the toxicity events.