gemcitabine + S-1

Gemcitabine + S-1 is a combination chemotherapy regimen used primarily in the treatment of various solid tumors, including pancreatic cancer and other gastrointestinal cancers. Gemcitabine is a nucleoside analog (antimetabolite) that inhibits DNA synthesis by incorporation into DNA and inhibition of ribonucleotide reductase, leading to cell cycle arrest at the G1/S-phase boundary and induction of apoptosis[2][3][8]. S-1 is an oral fluoropyrimidine derivative composed of tegafur (a prodrug of 5-fluorouracil), gimeracil (an inhibitor of dihydropyrimidine dehydrogenase to increase 5-FU bioavailability), and oteracil (to reduce gastrointestinal toxicity). The combination leverages the synergistic cytotoxic effects on rapidly dividing tumor cells through dual inhibition of DNA synthesis pathways.

Brand names

Gemzar (for gemcitabine)

Other names

gemcitabine hydrochloridetegafur/gimeracil/oteracil