PD-1 inhibitor versus bevacizumab in combination with platinum-based chemotherapy for first-line treatment of advanced lung adenocarcinoma: A retrospective-real world study.

BACKGROUND: Chemotherapy combined with immunotherapy or anti-vascular therapy is both recommended by guidelines for first-line treatment of lung adenocarcinoma. However, no head-to-head clinical trial has ever compared which strategy is the optimal choice. This real-world retrospective study was done to compare the efficacy and treatment-related adverse events of immunotherapy and bevacizumab in combination with chemotherapy.

PATIENTS AND METHODS: From January 2018 to March 2021, we retrospectively collected 276 patients with advanced lung adenocarcinoma managed with chemotherapy combined with bevacizumab or PD-1 inhibitors at our center. Among them, 139 patients were treated with chemotherapy combined with bevacizumab, while 137 patients were treated with chemotherapy combined with PD-1 inhibitors. After receiving four cycles of combination therapy, all patients received maintenance therapy until disease progression. Progression-free survival (PFS), overall response rate (ORR), overall survival (OS), disease control rate (DCR), and adverse events (AE) were analyzed between the two groups.

RESULTS: Compared to patients who received anti-vascular therapy, patients who underwent immunotherapy achieved better PFS (7.3 months vs. 10 months, p = 0.002) while ORR (40.9% vs. 51.1%, p = 0.093), as well as OS (18 months vs. 24 months, p = 0.060), had no statistical difference between the two groups. In the PD-L1-negative population, there was no statistical difference in PFS and OS between the two groups. (8.0 months VS. 6.0 months, p = 0.738; and 19 months vs. 13 months, p = 0.274). In the PD-L1-positive population, there was a significant benefit in PFS in the population receiving immunotherapy (7.0 months vs. 10.0 months, p = 0.009). Proteinuria and hypertension occurred more frequently in the bevacizumab-treated group (p = 0.001 and p = 0.002), whereas immune-related pneumonia and hypothyroidism occurred more frequently in the immunotherapy-treated group (p = 0.007 and p = 0.030).

CONCLUSIONS: The addition of a PD-1 inhibitor was superior to bevacizumab in terms of PFS among patients with advanced lung adenocarcinoma. PD-L1-positive patients appeared to exhibit better PFS, OS, and ORR. Toxic reactions were manageable in both groups.