Neoadjuvant immunochemotherapy with adebrelimab combined with the TP regimen for locally advanced OSCC: early results of a single-arm phase II clinical trial.

[BACKGROUND] This study aimed to investigate the efficacy of a PD-L1 inhibitor combined with chemotherapy in the treatment of locally advanced oral squamous cell carcinoma (OSCC).

[MATERIALS AND METHODS] This study was designed as a single-arm phase II trial, and a total of 30 patients were enrolled. All patients were pathologically confirmed to have head and neck squamous cell carcinoma. Patients received paclitaxel, carboplatin, and adebrelimab every 3 weeks as a treatment cycle, followed by surgery after three cycles of treatment. The primary endpoint was the postoperative pathological complete response (PCR) rate. The secondary endpoints included the objective response rate (ORR), major pathological response (MPR) rate, 2-year disease-free survival rate, and 2-year and 5-year overall survival rates. This study was conducted without using artificial intelligence (AI) tools in accordance with the TITAN Guidelines 2025.

[RESULTS] Among the 30 patients, 28 completed the full three cycles of immunochemotherapy, with an ORR of 60.7%. One patient dropped out, and one patient (3.3%) experienced grade 3-4 adverse reactions, leading to discontinuation after the first cycle. In the per-protocol population, 10 patients (35.7%) achieved a PCR in both the primary lesion and lymph nodes, whereas 18 patients (64.3%), including those with a PCR, achieved a MPR. Additionally, 20 patients (71.4%) achieved clinical to pathological downstaging. Common adverse reactions included alopecia (30; 100%), fatigue (7; 23.3%), anemia (24; 80%), hyperthyroidism (2; 6.7%), and pruritus (5; 16.7%).

[CONCLUSIONS] Preoperative neoadjuvant immunochemotherapy effectively improved the PCR rate in patients with locally advanced OSCC. PD-L1 inhibitors combined with chemotherapy have promising preliminary efficacy in patients with resectable locally advanced OSCC. However, additional follow-up is needed to obtain more comprehensive survival data and further validate these initial observations.