Efficacy and Safety of Cadonilimab in Digestive System Neoplasms: A Systematic Review and Single-Arm Meta-Analysis

Objective: This study aimed to systematically evaluate the efficacy and safety of cadonilimab in the treatment of digestive system neoplasms. Methods: PubMed, Embase, Cochrane Library, Web of Science, Wiley Online Library, CNKI, Wanfang Data, CBM, and VIP databases were systematically searched to collect randomized controlled trials, non-randomized studies, and real-world studies investigating cadonilimab for the treatment of digestive system neoplasms. The initial search spanned from the inception of the databases to 4 February 2026, with an update search conducted in June 2026. Meta-analysis was performed using Stata 16.0 to systematically assess efficacy and safety outcomes. Results: A total of 10 studies, predominantly single-arm or retrospective, were included in this meta-analysis. Regarding the primary outcomes, because of the clinical heterogeneity across tumor types, pooled estimates should be interpreted as a summary across diverse diseases rather than as a single-tumor estimate. The overall pooled disease control rate (DCR) was 84% (95% CI = 76-91%), with tumor-specific DCRs of 87% in ESCC, 79% in HCC, 88% in G/GEJ adenocarcinoma, and 86% in PDAC. The pooled incidence of any-grade treatment-related adverse events (TRAEs) was 98% (95% CI = 95-100%), and the pooled incidence of any-grade immune-related adverse events (irAEs) was 32% (95% CI = 18-47%). For secondary outcomes: The partial response (PR) rate was 33% (95% CI = 21-46%), and the progressive disease (PD) rate was 11% (95% CI = 5-18%). The pooled incidence of grade ≥ 3 TRAEs was 52% (95% CI = 38-66%), and the pooled incidence of grade ≥ 3 irAEs was 11% (95% CI = 8-16%). However, incomplete reporting of low-frequency AEs across studies likely underestimates the pooled irAE rate. Conclusions: This study suggests that cadonilimab has the potential for antitumor activity in digestive system neoplasms. The observed safety profile was consistent with the known toxicities of immunotherapy, with notably high rates of TRAEs warranting vigilant monitoring. These findings should be considered hypothesis-generating and are insufficient to establish clinical benefit.