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Gemcitabine + S-1

AstraZeneca · Phase 3 active Small molecule

Gemcitabine + S-1 is a Cytotoxic chemotherapy combination Small molecule drug developed by AstraZeneca. It is currently in Phase 3 development for Pancreatic cancer, Biliary tract cancer, Gastric cancer. Also known as: Background Gemcitabine-based Chemotherapy Regimen, This regimen is not allowed for countries in the European Union., gemzar, TS-1.

Gemcitabine and S-1 are cytotoxic chemotherapy agents that work synergistically to inhibit DNA synthesis and cell division in cancer cells.

Gemcitabine and S-1 are cytotoxic chemotherapy agents that work synergistically to inhibit DNA synthesis and cell division in cancer cells. Used for Pancreatic cancer, Biliary tract cancer, Gastric cancer.

Likelihood of approval
64.3% 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.
  • Big-pharma sponsor +3.0pp
    AstraZeneca is a top-20 pharma sponsor — historical approval rates run ~3pp above average due to scale, regulatory experience, and trial-design quality.
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 nameGemcitabine + S-1
Also known asBackground Gemcitabine-based Chemotherapy Regimen, This regimen is not allowed for countries in the European Union., gemzar, TS-1
SponsorAstraZeneca
Drug classCytotoxic chemotherapy combination
TargetRibonucleotide reductase, DNA polymerase, thymidylate synthase
ModalitySmall molecule
Therapeutic areaOncology
PhasePhase 3

Mechanism of action

Gemcitabine is a nucleoside analog that inhibits ribonucleotide reductase and DNA polymerase, leading to DNA strand breaks and apoptosis. S-1 is an oral fluoropyrimidine prodrug that inhibits thymidylate synthase and incorporates into DNA/RNA, enhancing the cytotoxic effects when combined with gemcitabine. This combination leverages complementary mechanisms to improve efficacy in solid tumors.

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 Gemcitabine + S-1

What is Gemcitabine + S-1?

Gemcitabine + S-1 is a Cytotoxic chemotherapy combination drug developed by AstraZeneca, indicated for Pancreatic cancer, Biliary tract cancer, Gastric cancer.

How does Gemcitabine + S-1 work?

Gemcitabine and S-1 are cytotoxic chemotherapy agents that work synergistically to inhibit DNA synthesis and cell division in cancer cells.

What is Gemcitabine + S-1 used for?

Gemcitabine + S-1 is indicated for Pancreatic cancer, Biliary tract cancer, Gastric cancer.

Who makes Gemcitabine + S-1?

Gemcitabine + S-1 is developed by AstraZeneca (see full AstraZeneca pipeline at /company/astrazeneca).

Is Gemcitabine + S-1 also known as anything else?

Gemcitabine + S-1 is also known as Background Gemcitabine-based Chemotherapy Regimen, This regimen is not allowed for countries in the European Union., gemzar, TS-1.

What drug class is Gemcitabine + S-1 in?

Gemcitabine + S-1 belongs to the Cytotoxic chemotherapy combination class. See all Cytotoxic chemotherapy combination drugs at /class/cytotoxic-chemotherapy-combination.

What development phase is Gemcitabine + S-1 in?

Gemcitabine + S-1 is in Phase 3.

What are the side effects of Gemcitabine + S-1?

Common side effects of Gemcitabine + S-1 include Neutropenia, Anemia, Thrombocytopenia, Nausea and vomiting, Diarrhea, Fatigue.

What does Gemcitabine + S-1 target?

Gemcitabine + S-1 targets Ribonucleotide reductase, DNA polymerase, thymidylate synthase and is a Cytotoxic chemotherapy combination.

Related

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