Multicenter phase 1b study of first-line ivonescimab plus etoposide and carboplatin for extensive-stage small cell lung cancer

Ivonescimab is a humanized IgG1 bispecific anti-PD-1/VEGF antibody. A multicenter phase 1b study in China evaluated the combination of ivonescimab with etoposide and carboplatin (four cycles, followed by ivonescimab maintenance) for extensive-stage small cell lung cancer (ES-SCLC). The ORR was 80.0% and the disease control rate was 91.4%. Grade 3 or worse treatment-related adverse events (TRAEs) were observed in 60%; the most frequent toxicities were decreased neutrophil count (22.9%), decreased white blood cell count (14.3%), and anemia (14.3%). Adverse events with potential immunologic etiology, most of them grade 1 or 2, occurred in 40.0%. TRAEs leading to death were reported in 5.7%. The authors conclude that ivonescimab in combination with etoposide and carboplatin was well-tolerated and showed promising antitumor activity in patients with ES-SCLC.