A prospective, single-arm, phase II study of adebrelimab plus carboplatin and albumin-bound taxanol as neoadjuvant therapy in patients with resectable locally advanced head and neck squamous cell carcinoma.

6034 Background: Currently, clinical studies have shown that patients with tumor remission after preoperative induction chemotherapy have a higher survival rate and a lower risk of distant metastasis, but the pathological complete remission rate of tumor after surgery is low. With the rise of tumor immunology, more and more immunotherapy methods have been applied to the treatment of clinical tumors. In terms of head and neck squamous cell carcinoma, we hereby investigate the efficacy of a PD-L1 inhibitor (Adebrelimab) combined with chemotherapy in patients with resectable advanced head and neck squamous cell carcinoma. Methods: This study hypothesized that preoperative induction of PD-L1 inhibitors combined with chemotherapy in patients with resectable advanced head and neck squamous cell carcinoma was superior to conventional chemotherapy regiments recommended by NCCN guidelines. As a course of treatment every three weeks, albumin-bound paclitaxel 260 mg/m2, carboplatin AUC=5 and Adebrelimab 1200 mg were given intravenously on the first day of every three weeks. After three doses, surgery was performed and radiotherapy was performed according to the stage of the tumor. The main index observed in this study was postoperative pathological complete response rate (PCR), and the secondary index was major pathological response rate (MPR) and 2-year survival rate (OS). Results: As of December 31, 2024, a total of 30 patients were enrolled in the study. Among them, the median age was 52 years, and 23 patients were male. During immunochemotherapy, the most common adverse reactions were alopecia (100%, 30/30), pruritus (16%, 5/30), and limb weakness (60%, 18/30). At present, 26 patients have completed all preoperative neoadjuvant therapy and successfully received surgical treatment. By comparing the MRI imaging images of these patients before and after medication, the efficacy evaluation of 14 patients was PR (53.9%, 14/26), 1 patient was CR (3.8%, 1/26), 1 patient was PD (3.8%, 1/26), and 10 patients was SD (38.5%, 10/26). In postoperative pathological specimens, 12 patients achieved pathological complete response (PCR: 46%, 12/26) and 3 patients achieved major pathological response (MPR: 11.5%, 3/26). We will follow up these patients and calculate their 2-year survival rate (OS). This study is still ongoing. Conclusions: In terms of head and neck squamous cell carcinoma, Phase I clinical studies have confirmed the therapeutic safety and tumor activity of PD-L1 inhibitors. In this Phase II study, the PD-L1 inhibitor (Adebrelimab) demonstrated a favorable therapeutic response to locally advanced head and neck squamous cell carcinoma, and we look forward to final therapeutic data. Clinical trial information: NCT06016413 .