Neoadjuvant tislelizumab with afatinib for locally advanced head and neck squamous cell carcinoma (neoCHANCE-1): An open-label, single-arm, phase 2 study.

Abstract

6073 Background: For patients with locally advanced head and neck squamous cell carcinoma (HNSCC), even receiving surgery with adjuvant radiotherapy or chemoradiotherapy, those remain at high risk of recurrence or metastasis. Neoadjuvant immunotherapy has been used in HNSCC, but provides only modest pathological response. Given single agent activity and unique mechanism of action of immune checkpoint inhibitors and epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), we aimed to evaluate the antitumour activity and safety of neoadjuvant PD-1 blockade with EGFR inhibition in locally advanced HNSCC. Methods: This open-label, single-arm, phase 2 trial was done at a a tertiary hospital in China. Eligible patients were aged 18 years or older and had resectable HNSCC disease, had an Eastern Cooperative Oncology Group performance status of 0–1, had at least one measurable target lesion according to the RECIST 1.1, had no prior antitumor therapy for HNSCC. Patients received neoadjuvant treatment with intravenous tislelizumab (200 mg) on the first day of each 3 week, with totally two cycles and orally afatinib (30 mg) starting on the first treatment day and ending on the day before surgery, with totally six weeks, and then patients proceeded to receive surgical resection. The primary endpoint was major pathological response, defined as the presence of 10% or less residual viable tumour at the time of surgery. Results: A total of 25 patients were enrolled completed the neoadjuvant therapy. Eight of 23 evaluable patients exhibited a major pathological response (MPR) (35%; 95% confidence interval [CI], 16%—57%), of which four had a complete pathological response of primary tumor (17%, 95%CI, 5%—39%). The overall response rate was 48% (12/25, 95%CI: 28%—69%) and disease control rate was 100% (25/25, 95%CI: 86%—100%). Common grade 3—4 adverse events included diarrhea (5/25 [20%]), hypokalemia (4/25 [16%]) and rash (3/25 [12%]). No treatment related fatalities were observed. Immunologically, post-neoadjuvant treatment demonstrated increased CD3, CD8, and CD56 expression within the tumor microenvironment. The increase of CD8 and CD56 expression level was significant higher in patients achieving MPR, along with elevated circulatory NK cells at baseline, compared to those in patients achieving non-MPR. Conclusions: This study underscores encouraging antitumor activity, manageable toxicity profile and promising immune activation elicited by neoadjuvant tislelizumab plus afatinib for HNSCC, which deserves further assessment. Clinical trial information: NCT05517330 .