Immune activation following envafolimab plus endostar in advanced non-small cell lung cancer: a retrospective, single-arm study

Immune checkpoint inhibitors (ICIs) are a key therapeutic approach for advanced non‑small cell lung cancer (NSCLC). However, many patients experience limited benefits, primarily due to acquired resistance. Envafolimab, a subcutaneous PD‑L1 inhibitor, and endostar, a recombinant human endostatin, may exert synergistic anti-tumor effects through immune activation and vascular normalization. This study investigated the effectiveness and safety of envafolimab combined with endostar in patients with advanced NSCLC, including a subgroup that progressed after previous anti-PD-1/PD-L1 therapy. This retrospective, single‑arm study was conducted at Beijing Cancer Hospital between May 2022 and May 2025. Patients received subcutaneous envafolimab (200 mg, day 1) and a continuous intravenous infusion of endostar (210 mg over 72 h) every 3 weeks until disease progression or unacceptable toxicity. Tumor responses were evaluated using RECIST v1.1, and adverse events (AEs) were graded according to CTCAE v5.0. Survival outcomes, including overall survival (OS) and progression-free survival (PFS), were estimated using the Kaplan–Meier method. A total of 20 patients, with a median age of 69 years, were enrolled in this study. The treatment demonstrated promising efficacy, achieving an objective response rate (ORR) of 30% and a disease control rate (DCR) of 60%. With a median follow-up of 21.8 months, the median progression-free survival (PFS) was 16.5 months, and the median overall survival (OS) was not reached. Furthermore, there were no reported cases of grade ≥ 3 treatment-related adverse events (TRAEs) or treatment-related deaths, indicating that the combination regimen was exhibited a favorable safety profile. The combination of envafolimab and endostar demonstrated promising efficacy and a manageable safety profile in patients with advanced NSCLC. Notably, it also exhibited preliminary clinical activity in the subgroup with disease progression following prior PD-1 blockade. These findings suggest that dual targeting with a PD-L1 inhibitor and anti-angiogenic therapy represents a viable strategy to potentially overcome immune resistance. Large-scale prospective studies are warranted to validate these clinical benefits and identify predictive biomarkers for treatment response.