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TS-1 (S-1)

National Cancer Center, Korea · Phase 3 active Small molecule ✓ Verified May 2026

TS-1 (S-1) is a Fluoropyrimidine antimetabolite Small molecule drug developed by National Cancer Center, Korea. It is currently in Phase 3 development for Gastric cancer, Colorectal cancer, Pancreatic cancer. Also known as: S-1.

TS-1 (S-1) is an oral fluoropyrimidine combination that inhibits thymidylate synthase and other enzymes in the pyrimidine synthesis pathway to suppress tumor cell DNA synthesis.

TS-1 is a medication used to treat Recurrent or Metastatic Gastric Cancer, Gastric Cancer, Advanced Non-Small Cell Lung Cancer, and Biliary Tract Neoplasm. It is administered as part of treatment regimens including SP, FL/Tax, and FL/Doc.

Likelihood of approval
61.3% vs 58.3% industry baseline
If approved by FDA: likely 2028–2030
Steps remaining: NDA/BLA submission
Confidence: High
Why this estimate
  • Baseline phase 3 → approval rate +58.3pp
    Industry-wide phase 3 drugs reach approval ~58.3% of the time (BIO/Informa 2023 industry benchmark across all therapeutic areas).
  • Oncology Phase 3 boost +3.0pp
    Oncology Phase 3 trials have higher approval rates (~61%) than the cross-industry average due to clearer endpoints and FDA oncology pathway.
Predicted approval windows by jurisdiction (conditional on FDA approval)
Regulator Country Likely year Lag vs FDA
FDA US 2028–2030
EMA EU 2029–2031 +0.7 yr
MHRA GB 2029–2031 +0.7 yr
Health Canada CA 2029–2032 +0.9 yr
TGA AU 2029–2032 +1.2 yr
PMDA JP 2029–2032 +1.5 yr
NMPA CN 2030–2033 +2.3 yr
MFDS KR 2029–2032 +1.4 yr
CDSCO IN 2029–2033 +1.8 yr
ANVISA BR 2030–2033 +2.3 yr

Hover any row for the lag rationale. Lag estimates are reduced when the drug has FDA Breakthrough or EMA PRIME designation (sponsors file globally in parallel).

Estimate based on the BIO/Informa industry phase transition rates plus per-drug modifiers for therapeutic area, sponsor type, FDA designations, mechanism, and trial design. Per-jurisdiction lags from Tufts CSDD international approval studies. Not investment, clinical or regulatory advice. Methodology: /methodology#likelihood.

At a glance

Generic nameTS-1 (S-1)
Also known asS-1
SponsorNational Cancer Center, Korea
Drug classFluoropyrimidine antimetabolite
TargetThymidylate synthase
ModalitySmall molecule
Therapeutic areaOncology
PhasePhase 3

Mechanism of action

S-1 is a fixed-dose combination of tegafur (a prodrug of 5-fluorouracil), gimeracil (a dihydropyrimidine dehydrogenase inhibitor), and oteracil (a orotate phosphoribosyltransferase inhibitor). This combination enhances 5-FU bioavailability and reduces gastrointestinal toxicity by modulating fluoropyrimidine metabolism. It acts as an antimetabolite, primarily targeting thymidylate synthase to disrupt DNA synthesis in rapidly dividing cancer cells.

Approved indications

Common side effects

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

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

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

Frequently asked questions about TS-1 (S-1)

What is TS-1 (S-1)?

TS-1 (S-1) is a Fluoropyrimidine antimetabolite drug developed by National Cancer Center, Korea, indicated for Gastric cancer, Colorectal cancer, Pancreatic cancer.

How does TS-1 (S-1) work?

TS-1 (S-1) is an oral fluoropyrimidine combination that inhibits thymidylate synthase and other enzymes in the pyrimidine synthesis pathway to suppress tumor cell DNA synthesis.

What is TS-1 (S-1) used for?

TS-1 (S-1) is indicated for Gastric cancer, Colorectal cancer, Pancreatic cancer, Biliary tract cancer.

Who makes TS-1 (S-1)?

TS-1 (S-1) is developed by National Cancer Center, Korea (see full National Cancer Center, Korea pipeline at /company/national-cancer-center-korea).

Is TS-1 (S-1) also known as anything else?

TS-1 (S-1) is also known as S-1.

What drug class is TS-1 (S-1) in?

TS-1 (S-1) belongs to the Fluoropyrimidine antimetabolite class. See all Fluoropyrimidine antimetabolite drugs at /class/fluoropyrimidine-antimetabolite.

What development phase is TS-1 (S-1) in?

TS-1 (S-1) is in Phase 3.

What are the side effects of TS-1 (S-1)?

Common side effects of TS-1 (S-1) include Nausea and vomiting, Diarrhea, Anorexia, Bone marrow suppression (leukopenia, thrombocytopenia), Stomatitis, Hand-foot syndrome.

What does TS-1 (S-1) target?

TS-1 (S-1) targets Thymidylate synthase and is a Fluoropyrimidine antimetabolite.

Related

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing