Irinotecan combined with oxaliplatin and S-1 in patients with metastatic pancreatic adenocarcinoma: a single-arm, three-centre, prospective study

OBJECTIVE: To study the efficacy and toxicity of irinotecan combined with oxaliplatin and S-1 in patients with metastatic pancreatic adenocarcinoma. PATIENTS AND METHODS: Previously untreated patients with cytologically or histologically confirmed metastatic pancreatic adenocarcinoma underwent a treatment regimen consisting of an intravenous infusion of irinotecan 165 mg/m(2) and oxaliplatin 85 mg/m(2) on day 1, and oral S-1 40 mg/m(2) twice daily on days 1–14, repeating the regimen every 21 days until one of the following occurred: disease progression, intolerable toxicity, or patient death. The primary endpoint was overall survival (OS), and the secondary endpoints were progression-free survival (PFS), response rate, toxicity, and quality of life. This ongoing study had been registered on ClinicalTrials.gov, NCT03726021. RESULTS: A total of 41 patients were enrolled in this study, 18 men and 23 women. The median PFS was 4.33 months [95% confidence interval (CI): 2.83–5.88] and the median OS was 11.00 months (95% CI: 9.16–12.84). There were no instances of a complete response; the partial response, stable disease, and disease progression rates were 39.02% (16/41), 29.27% (12/41), and 31.71% (13/41), respectively. The most common adverse side effects were mild to moderate nausea, vomiting, neutropenia, and thrombocytopenia. Grade 3 or 4 neutropenia and thrombocytopenia were observed in 29.27% (12/41) and 12.20% (5/41) of the patients, respectively. No treatment-related death was observed. CONCLUSION: Irinotecan combined with oxaliplatin and S-1 is a safe and effective treatment for metastatic pancreatic adenocarcinoma, and any toxicities are mild to moderate and tolerable. A larger study population is needed for further evaluation.