- Receiving a concomitant treatment interacting with TS-1, cisplatin or RAD001. Flucytosine (a fluorinated pyrimidine antifungal agent) Antivirals such as sorivudine, ramivudine, brivudine or other chemically related agents, warfarin, phenprocoumon, phenytoin, allopurinol, immunosuppressive agents. Strong and moderate inhibitors or inducers of P-glycoprotein, CYP3A4 and CYP3A5 (appendix A) are not eligible; a minimal of 2 weeks wash- out period will be required after stop such medications