Abstract Background Despite advancements in systemic chemotherapy and immune checkpoint inhibitors (ICIs), advanced non-small cell lung canc
Abstract Background Despite advancements in systemic chemotherapy and immune checkpoint inhibitors (ICIs), advanced non-small cell lung cancer (NSCLC) continues to exhibit poor prognosis, underscoring an urgent need for safer and more effective therapeutic strategies. This study investigates the safety profile and biological effects of bronchial arterial infusion (BAI)-administered anti-PD-1 monoclonal antibody (aPD-1 mAb) using a preclinical beagle model and a clinical cohort of advanced NSCLC patients. Methods In preclinical evaluations, male beagles (n = 3/group) were randomized to receive 5 mg/kg aPD-1 mAb via BAI or intravenous routes (Venous group). Safety assessments included longitudinal imaging, biochemical analyses, and histopathological evaluation. Clinically, patients with advanced NSCLC meeting stringent inclusion criteria underwent BAI immunotherapy, with systematic monitoring of adverse events (AEs). Results Both administration routes demonstrated comparable safety in canines, with no evidence of immune-related pneumonitis or structural lung alterations on CT or histology. Transient AEs (e.g., hematoma, lameness) resolved spontaneously. Pharmacokinetic analysis revealed similar systemic drug concentrations and tissue distribution between BAI and Venous groups (all p > 0.05). Biochemical profiling identified isolated mild LDH elevation in one BAI-treated canine. Notably, the BAI group exhibited significantly enhanced systemic IL-2 levels (80.15 ± 5.24 pg/mL vs. 66.47 ± 5.24 pg/mL in Venous groups, p = 0.001) at day 28, paralleled by elevated pulmonary IL-2 expression (626.90 ± 18.49 vs. 559.18 ± 45.61 pg/mg, p = 0.03). In the clinical cohort (n = 17; 94.1% male, mean age 61.6 ± 7.1 years), BAI immunotherapy was well-tolerated with mild AEs including nausea (n = 1), dyspnea (n = 1), atrial fibrillation (n = 1), and puncture-site hematoma (n = 1). No severe immune-related toxicities (e.g., pneumonitis) emerged during follow-up. Conclusion Our study suggest the preliminary safety and feasibility of delivering aPD-1 mAb via BAI in both canine models and NSCLC patients.