The efficacy and safety of a novel PD-1/CTLA-4 bispecific antibody cadonilimab (AK104) in advanced non-small cell lung cancer: A multicenter retrospective observational study in China.

e20518 Background: Treatment choice for advanced non-small cell lung cancer (NSCLC) after front-line immuno-chemotherapy therapy is limited. As the first approved dual programmed cell death-1(PD-1) / cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) bispecific antibody worldwide, cadonilimab combined with anlotinib, a vascular epidermal growth factor tyrosine kinase inhibitor, showed potential anti-tumor activity in advanced NSCLC patients resistant to anti-PD-1/ programmed cell death ligand-1(PD-L1) antibodies in a phase Ib/II clinical trial. Methods: We retrospectively collectedthe efficacy and safety data in advanced NSCLC patients treated with cadonilimab in later therapy lines. The primary endpoints were objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS) and safety results. The secondary endpoints were overall survival (OS). Results: Totally, 41 advanced NSCLC patients who were refractory to previous chemotherapy and anti-PD-1/PD-L1 therapy and treated with later line cadonilimab-based regimens were enrolled. More than half of patients received cadonilimab as a fourth or later line of treatment. Until the data cut-off date (August 29, 2023), the treatment efficacy of 23 patients could be evaluated. One (4.3%) patient had partial response, 8 (34.8%) patients had stable disease, and 14 (60.9%) patients progressed. The ORR and DCR were 4.3% and 39.1%, respectively. The median PFS of all evaluated patients was 108.0 days (95% confidence interval: 62.3-153.7). Due to the short follow-up, median OS has not been reached yet. Treatment-related adverse events (TRAEs) and immune-related adverse events (irAEs) occurred in 26(63.4%) and 9(22%) patients, respectively. The most common AEs included gamma-glutamyl transferase elevation (17.1%), coughing (14.6%), and fatigue (12.2%). Five patients (12.2%) experienced grade≥3 AEs. Two patients temporarily paused medication due to Grade 2 rash. One patient and 2 patients permanently discontinued medication due to Grade 3 myocarditis and Grade 2 infusion reactions, respectively. Metabolomics results showed that lipids and lipid-like molecules were rich in stools of patients responsive to cadonilimab treatment. Conclusions: In this heavily treated advanced NSCLC patient cohort, cadonilimab-based regimens only showed moderate anti-tumor efficacy with a generally tolerable and manageable safety profile. More evidence supporting administration of cadonilimab is needed in NSCLC patients refractory to previous anti-PD-1/PD-L1 therapy.