Sintilimab + Nab-PP Combined with Recombinant Human Vascular Endothelial Inhibitor for Locally Advanced/Advanced and Recurrent Metastatic Squamous Non-Small Cell Lung Cancer: Study Protocol for a Single-Arm, Multi-Centre Phase II Clinical Study.

BackgroundSquamous non-small cell lung cancer (sq-NSCLC) remains a major cause of cancer-related mortality in world. While immunotherapy combined with chemotherapy has improved outcomes, response rates and survival remain suboptimal. Anti-angiogenic agents, such as recombinant human vascular endothelial inhibitor (endostar), may enhance the efficacy of immune checkpoint inhibitors (ICIs) by modulating the tumor microenvironment. This phase II trial evaluates the combination of endostar, sintilimab, and chemotherapy in advanced sq-NSCLC.ObjectiveTo assess the efficacy and safety of endostar combined with sintilimab and chemotherapy in patients with advanced sq-NSCLC, focusing on progression-free survival (PFS) as the primary endpoint. Secondary endpoints include overall survival (OS), duration of response (DoR), disease control rate (DCR), and safety. Exploratory analyses will investigate biomarkers and quality of life.MethodsThis prospective, single-arm, multicenter phase II trial (NCT06746179) will enroll 64 patients with advanced sq-NSCLC (stage IIIB-IV) and negative driver gene mutations. Patients will receive endostar (210 mg/dose, 72 h), sintilimab (200 mg/dose), and chemotherapy (nab-pp, carboplatin/cisplatin + albumin-bound paclitaxel) every 3 weeks for up to 6 cycles, followed by maintenance therapy until progression or intolerable toxicity. Radiological assessments will occur every 8 weeks initially, then every 12 weeks. Biomarker analysis and quality of life assessments will be performed.