Gemcitabine + Cisplatin + S-1 Treatment for Advanced Cholangiocarcinoma: Cost-Effective, with Better Progression-Free Survival and Objective Response Rates Versus Standard Treatment with Gemcitabine + Cisplatin + Durvalumab

Objectives: To evaluate the prognosis and costs of gemcitabine + cisplatin + S-1 (GCS) versus gemcitabine + cisplatin + durvalumab (GCD), the standard of care for advanced cholangiocarcinoma, in a prospective observational study. Methods: We enrolled 52 patients who received GCS as first-line treatment from April 2020 to April 2024 and 44 patients who received GCD from March 2023 to April 2024. Overall survival (OS), progression-free survival (PFS) and objective response rate (ORR) were examined. Propensity score matching (PSM) was performed to balance baseline characteristics between the two groups, and OS, PFS and ORR were then analysed in the matched cohorts. Drug costs were compared until the end of treatment. Results: OS was not significantly different between GCD and GCS at 12.2 months (95% confidence interval [CI]: 7.5–16) versus 18.6 months (95% CI: 13.3–21.9) (p=0.0935). PFS was 6.26 months (95% CI: 3.2–8.8) versus 10.2 months (95% CI: 6.5–13.8) for GCD versus GCS, respectively (p=0.0151). The ORR was also better for GCD (36.5%) than for GCS (15.9%) (p=0.0234). Twenty-seven cases were included in the PSM analysis, which showed no significant differences in OS and better PFS (6.3, 95% CI: 2.8–9.3 versus 11.4, 95% CI: 6.2–15.0; p=0.0142) and ORR (14.8% versus 40.7%; p=0.0309) for GCS versus GCD, respectively. The cost of GCD versus GCS was 113,472 ± 72,198 versus 4622 ± 3109 US dollars by treatment end (p=0.0001). Conclusions: GCS was significantly less expensive than GCD and showed comparable OS and better PFS and ORR.