Phase I study of combination chemotherapy consisting of paclitaxel, cisplatin, and S-1 in patients with unresectable gastric cancer (KOGC-02)

Background: Triplet combination chemotherapy has the potential to improve the prognosis of patients with unresectable gastric cancer. We conducted a phase I trial of triplet combination chemotherapy consisting of paclitaxel, cisplatin, and S-1 (PCS) for unresectable gastric cancer. Patients and Methods: Patients with metastatic or incurable disease were enrolled. S-1 was administered on days 1-14. Paclitaxel and cisplatin were infused on days 1 and 15. The starting doses of paclitaxel and cisplatin were 100 and 20 mg/m ², respectively. Dose levels of paclitaxel and cisplatin were escalated as follows: 120 and 20 mg/m², respectively (level 2); 120 and 30 mg/m², respectively (level 3). End-points: Dose-limiting toxicities included grade 3 nausea, vomiting, and general fatigue, and grade 4 febrile neutropenia. The maximum tolerated dose and recommended dose were established at level 3 and level 2, respectively. Conclusion: Although further clinical trials are recommended to more thoroughly evaluate safety and efficacy, PCS appears to be an excellent candidate for a standard treatment strategy for unresectable gastric cancer.