Utility of atezolizumab plus bevacizumab, carboplatin, and paclitaxel combination for the treatment of advanced non-squamous non-small cell lung cancer patients with malignant pleural effusion

Abstract

Background: Malignant pleural effusion (MPE) remains a negative prognostic factor in non-small cell lung cancer (NSCLC), even after the emergence of immune checkpoint inhibitors. Vascular endothelial growth factor (VEGF) plays a pivotal role in the pathogenesis of MPE. Bevacizumab, a humanized monoclonal antibody against VEGF, is a key agent for patients who develop MPE. However, it is unclear whether MPE is a poor prognostic factor in patients with advanced non-squamous NSCLC receiving treatment with the atezolizumab plus bevacizumab, carboplatin, and paclitaxel (ABCP) regimen. Moreover, the effect of ABCP on MPE control is unknown. This study aimed to elucidate the efficacy and safety of ABCP for nonsquamous NSCLC patients with MPE. Methods: We retrospectively analyzed consecutive patients with advanced non-squamous NSCLC who received treatment with ABCP (January 2019–September 2023). Patients were divided into two groups (non-MPE and MPE), and treatment outcomes were compared. In the MPE group, treatment efficacy for MPE control and toxicity were evaluated. Results: Of the 46 patients enrolled, 17 and 29 were included in the non-MPE and MPE groups, respectively. The objective response and disease control rates were not significantly different between the non-MPE and MPE groups (76.5% vs. 51.7%, P=0.13; 88.2% vs. 82.8%, P>0.99; respectively). Similarly, the median progression-free survival and median overall survival were not significantly different (9.9 vs. 10.1 months, P=0.87; 16.0 vs. 19.9 months, P=0.87, respectively). In the MPE group, 25 patients (86.2%) achieved MPE control lasting >8 weeks from the initiation of treatment with ABCP; the median progression-free survival without an unequivocal increase in MPE was 15.0 months. The incidence rates of grade ≥3 non-immune- and immune-related adverse events were 83% and 17%, respectively. There was no treatment-related death. Conclusions: The ABCP regimen may be a promising treatment option for non-squamous NSCLC patients with MPE.