Phase I study of combination therapy with S-1 and weekly docetaxel for advanced gastric cancer
Tomohiro Ozaki1, Kenji Tamura, Taroh Satoh
1Department of Medical Oncology, Kinki University School of Medicine, Nara Hospital, Otoda, Ikoma, Nara, Japan.
Background:
The primary objective of this study was to determine the maximum tolerated dose (MTD), the toxicity profile and the recommended dose (RD) for phase II of a combination of S-1 and weekly administration of docetaxel.
Patients And Methods:
Patients with histologically diagnosed recurrent or unresectable locally advanced gastric cancer were enrolled. A fixed oral dose of 80 mg/m2 S-1 was given for 3 weeks. Docetaxel was infused intravenously on day 1, 8 and 15, repeated every 5 weeks. A pharmacokinetic study was also performed.
Results:
A total of 14 patients were enrolled. One dose-limiting toxicity (DLT) (grade 3 diarrhea with febrile neutropenia) occurred at level 2. DLTs occurred in 3/5 patients at level 3, (grade 3 stomatitis, with febrile neutropenia or continuous grade 4 neutropenia). The pharmacokinetic study suggested no drug interactions. Overall response and disease control rates were 20% and 80%, respectively. The response rate at the RD (level 2) was 50%. Overall survival was 9.4 months.
Conclusion:
RD was level 2 (80 mg/m2 of S-1 for 3 weeks and 20 mg/m2 of docetaxel on day 1, 8 and 15, every 5 weeks). Dose intensities of S-1 and docetaxel were 48 mg/m2/week and 12 mg/m2/week, respectively. This regimen showed promising activity for advanced gastric cancer.
