Comparison of Real-world Efficacy and Safety of Atezolizumab and Durvalumab in Combination With Chemotherapy for First-line Treatment of Extensive-stage Small-cell Lung Cancer.

Abstract

The combination of programmed cell death ligand 1 inhibitors and platinum-based chemotherapy has become the standard treatment for first-line therapy in extensive-stage small-cell lung cancer (ES-SCLC). This study compared the efficacy and safety of atezolizumab plus chemotherapy and durvalumab plus chemotherapy in the treatment of ES-SCLC in clinical practice. We retrospectively analyzed 40 patients with ES-SCLC treated with atezolizumab plus chemotherapy or durvalumab plus platinum-based chemotherapy at the Fukuoka University Hospital between October 2019 and November 2022. Among the 40 patients, 20 were treated with atezolizumab and 20 were treated with durvalumab. There was no significant difference in patient characteristics between the two groups; five patients who received atezolizumab and one who received durvalumab showed a performance status of 2 or higher. The median progression-free survival of patients who received atezolizumab or durvalumab was 5.6 and 5.4 months, respectively (p=0.881). The median overall survival of patients who received atezolizumab or durvalumab was 10.0 and 17.1 months, respectively (p=0.163). The objective response rate of the patients who received atezolizumab or durvalumab was 80.0% and 85.0%, respectively. There was no significant difference in the incidence of immune-related adverse events between the groups. This retrospective study was the first to compare the efficacy and safety of PD-L1 antibody, atezolizumab or durvalumab, in combination with carboplatin and etoposide in treatment-naïve ES-SCLC Japanese patients in a real-world setting. Both regimens, atezolizumab or durvalumab with carboplatin and etoposide, were effective and well-tolerated in Japanese ES-SCLC patients, in line with clinical trial findings.