S-1 is an oral fluoropyrimidine, consisting of tegafur, a prodrug of 5-FU, and two bio-modulators, 5-chloro-2,4-dihydroxypyridine and potassium oxonate, which maintains high serum 5-fluorouracil levels and reduces gastrointestinal toxicity. S-1 has demonstrated efficacy in a variety of solid tumors, especially in Asian patients.
The bolded part seems to suggest that S-1 is more effective in Asian patients. Doesn’t mean that it’s not effective in Western patients. It might be effective, just not to the same extent.
EDIT: Here’s a study that confirmed that the maximum dose of S-1 tolerated by Western patients is lower than the dose tolerated by Japanese patients.
If my info is correct. S1 will be available in the States in a couple years.and is now under studied by the FDA for its effectiveness as compare to Xeloda.
Last year,when I attended the ASCO 2011 convention there was a poster about s1, and the gentleman on duty indicated that they will try to market S1 thru a larger drug company in the States. I will get more info about S1 in the up coming ASCO2012 convention.
Basically S1 is like the Xeloda (Capecitabine) that is current available in Europe and in the States. these are the prodrug of 5FU taken by mouth.
Keep in mind, S-1 therapy is only used in Asia. Western hospitals don’t use it. Western patients can’t take it because of genetic differences. It’s either ineffective or causes bad reaction (don’t remember the exact details).