S-1/Cisplatin
DrugPK Phase (Part 1), Beginning on Day 1 of the Pharmacokinetic Phase, 30 mg/m2 S-1 will be administered orally BID for 14 days (Days 1 through 14), followed by a 1-week recovery period.
On Day -2 and Day 14 of the Pharmacokinetic Phase, all patients will receive a single dose of 30 mg/m2 S-1 administered orally.
Extension Phase, Patients will receive S-1 at the dose that they tolerated in the PK Phase. S-1 will be administered orally BID for 2 weeks (Day 1 through Day 14) followed by a 1-week recovery period (Day 15 through Day 21). This cycle will be repeated every 3 weeks.