14047 Background: While gemcitabine (GEM) is the standard drug for chemotherapy against advanced pancreatic cancer, the development of multidrug therapies for improved outcome is important. We conducted multicentric combined chemotherapy with GEM and S-1 and report the results of the phase I trial. Methods: The subjects had unresectable pancreatic ductal cancer. The method of administration was single administration of GEM on the first day of the week from Level 1 to Level 4 at 400 to 1000 mg/m2, with concurrent administration of S-1 at 40 to 100 mg/day × 7 days, repeated every other week as a collaborative trial conducted at 3 facilities. The purpose was to determine the optimal dose with adverse events as an indicator. Results: Eighteen patients were enrolled (3 each at Levels 1, 2, 3 and 4’, 6 at Level 4). Average age was 60.9 years (38 - 71 years). There was no dose limiting toxicity (DLT) up to Level 3. Level 4 was the maximum tolerated dose since DLT was observed in 4/6 patients (mucositis 2, rash 1, anorexia 1), and no DLT was observed in 3 additional patients at Level 4’. The resulting recommended dose was Level 4 (GEM 1000 mg/m2, S-1 100 mg/day). For reference, partial response was observed in 5 patients, and median survival time at this stage is 336±39 days. Conclusions: The recommended dosage of GEM + S-1 combined chemotherapy for unresectable advanced pancreatic cancer was determined in a phase I trial. We intend to proceed to a phase II trial. No significant financial relationships to disclose.
A phase I trial of S-1 with concurrent radiotherapy for locally advanced pancreatic cancer