(A-119) Real-World Effectiveness of Low-Dose Nivolumab Plus Triple Metronomic Chemotherapy in Recurrent/Metastatic HNSCC: A Pragmatic Approach for Resource-Limited Settings

Background: Recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) poses a major challenge in low- and middle-income countries (LMICs) due to the high cost of immune checkpoint inhibitors (ICIs). While ICIs combined with chemotherapy improve survival, their limited affordability necessitates alternative strategies. Metronomic chemotherapy, with continuous low-dose drug administration, enhances anti-tumor immunity while reducing toxicity and cost. Low-dose nivolumab with triple metronomic chemotherapy (TMC-I) offers a promising, cost-effective alternative. This real-world study evaluates the effectiveness of TMC-I in R/M HNSCC, aiming to provide an affordable treatment option for resource-limited settings.

Objectives: To evaluate the clinical effectiveness of low-dose nivolumab combined with triple metronomic chemotherapy (TMC-I) in patients with recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC)
To assess overall survival (OS) and progression-free survival (PFS) associated with the TMC-I regimen
To analyze the objective response rate (ORR) and disease control rate (DCR) in patients receiving TMC-I
To analyze the safety and tolerability of the TMC-I regimen

Methods: This prospective observational study included 127 out of 250 screened adult patients with recurrent or newly diagnosed advanced HNSCC, treated with palliative intent, who had an Eastern Cooperative Oncology Group (ECOG) performance status of 0–1. Patients were recruited from three oncology centers and were followed until disease progression or death for a period of two years. Primary endpoints were objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). Kaplan-Meier analysis was used to estimate survival outcomes.

Results: The median age of patients was 50 years, with a male predominance. The objective response rate (ORR) was 60%. The median progression-free survival (PFS) was 14 months (95% CI: 9.47–13.01), while the median overall survival (OS) was 11 months (95% CI: 10.28–15.55). A statistically significant difference (p < 0.01) in OS and PFS was observed between patients who received initial chemotherapy followed by TMC-I and those who received upfront TMC-I. Additionally, clinical factors such as gender (p = 0.04) and tumor subsite (p = 0.0212) significantly impacted PFS. The rate of grade 3 and above adverse events was 46.1%.

Conclusions: TMC-I emerged as a promising, cost-effective alternative for recurrent or advanced HNSCC in resource-limited settings. It demonstrated favorable survival outcomes, safety and tolerability with treatment sequence and clinical factors influencing progression. Given its efficacy and affordability, TMC-I may serve as a viable option for improving patient care.