Anlotinib reversed resistance to PD-1 inhibitors in recurrent and metastatic head and neck cancers: a real-world retrospective study.

Patients with recurrent or metastatic head and neck cancers (R/M HNCs) are prone to developing resistance after immunotherapy. This retrospective real-world study aims to investigate whether the addition of anlotinib can reverse resistance to PD-1 inhibitors (PD-1i) and evaluate the efficacy and safety of this combination in R/M HNCs. Main outcomes included objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), duration of response (DOR), and safety. Potential biomarkers included PD-L1 expression, lipid index, and genomic profiling. Twenty-one patients with R/M HNCs were included, including 11 nasopharyngeal carcinoma (NPC), five head and neck squamous cell carcinoma (HNSCC), three salivary gland cancers (SGC), and two nasal cavity or paranasal sinus cancers (NC/PNC). Among all patients, ORR was 47.6% (95% CI: 28.6-66.7), with 2 (9.5%) complete response; DCR was 100%. At the median follow-up of 17.1 months, the median PFS and OS were 14.3 months (95% CI: 5.9-NR) and 16.7 months (95% CI:8.4-NR), respectively. The median DOR was 11.2 months (95% CI: 10.1-NR). As per different diseases, the ORR was 45.5% for NPC, 60.0% for HNSCC, 66.7% for SGC, and 50.0% for NC/PNC. Most treatment-related adverse events (TRAEs) were grade 1 or 2 (88.9%). The most common grades 3-4 TRAE was hypertension (28.6%), and two treatment-related deaths occurred due to bleeding. Therefore, adding anlotinib to the original PD-1i could reverse PD-1 blockade resistance, with a favorable response rate, prolonged survival, and acceptable toxicity, indicating the potential as a second-line and subsequent therapy choice in R/M HNCs.