Safety and Efficacy of the First Subcutaneous ICI, Envafolimab, in the Treatment of Advanced Lung Cancer Patients: A Real-World Study

Background: Envafolimab is a novel immune checkpoint inhibitor (ICI) with several advantages due to its subcutaneous administration. Phases I and II randomized controlled trials have demonstrated promising efficacy in treating colorectal and gastric cancer. However, the safety and efficacy of Envafolimab in patients with advanced lung cancer remain to be investigated. Methods: This retrospective, multicenter, open-label, single-arm cohort study examined real-world medical data from patients treated at four medical centers to assess the safety and efficacy of Envafolimab in treating patients with advanced lung cancer. The primary safety outcome was Envafolimab-related treatment-emergent adverse events (TEAEs) and immune-related adverse events (irAEs). The primary efficacy outcomes included overall survival (OS) and progression-free survival (PFS). Then, the relationship between clinical parameters and prognosis was investigated using univariate and multivariate regression analyses. Furthermore, the impact of tumor EGFR driver mutation status and PD-L1 expression on prognosis was explicitly explored in patients with nonsmall-cell lung cancer (NSCLC). Results: The cohort comprised 58 patients with a median follow-up time of 8.3 months (from March 1, 2022, to March 7, 2024). Envafolimab-related TEAEs and irAEs were observed in 53.4% and 27.6% of patients, respectively. No specific clinical factors were identified as being associated with irAEs. The median OS was 8.5 months (95% confidence interval [CI] 6.2-10.8), and the median PFS was 6.1 months (95% CI 3.8-8.3). For 47 patients with NSCLC, factors including ECOG PS > 2 (HR: 2.91, p = 0.015), Stage IV tumor (HR: 3.43, p = 0.043), and nonfirst-line Envafolimab treatment (HR: 3.27, p = 0.026) were associated with poor prognosis. Conclusion: Envafolimab demonstrates a tolerable safety profile and favorable efficacy. With its subcutaneous formulation, Envafolimab shows promising potential for treating advanced lung cancer.