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S-1 Chemotherapy

Asan Medical Center · Phase 3 active Small molecule

S-1 is a chemotherapy medication that works by inhibiting thymidylate synthase, thereby disrupting DNA synthesis and cell division.

S-1 is a chemotherapy medication that works by inhibiting thymidylate synthase, thereby disrupting DNA synthesis and cell division. Used for Metastatic gastric cancer, Metastatic pancreatic cancer.

At a glance

Generic nameS-1 Chemotherapy
SponsorAsan Medical Center
Drug classAntimetabolite
TargetThymidylate synthase
ModalitySmall molecule
Therapeutic areaOncology
PhasePhase 3

Mechanism of action

S-1 is a prodrug that is converted into 5-fluorouracil (5-FU) and other active metabolites, which then inhibit thymidylate synthase. This inhibition prevents the synthesis of thymidine, a nucleotide required for DNA replication and cell division. As a result, S-1 selectively targets rapidly dividing cancer cells, causing DNA damage and ultimately leading to cell death.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results