Protein / target

Antithrombin-III

SERPINC1P01008Homo sapiensSwiss-Prot
Clinically validated
Therapeutic maturity
10
Approved medicines
30
Clinical trials
Small-molecule tractable
Druggability
Structure with Ligand

Protein at a glance

Biological role

Serine-type endopeptidase inhibitor activity

Primary system

Haematologic system

Strongest disease association

Reduced antithrombin III activity

Genetic evidence · score 0.99

Therapeutic maturity

Clinically validated target

10 approved medicines against this target

Druggability

Small molecule

Open Targets tractability · Structure with Ligand

Clinical development

10 approved · 2 in clinical development

30 linked trials

Derived from structured UniProt, Open Targets and literature data on this page.

Protein profile

UniProt 2026_02

Canonical identity and biological annotation from UniProt.

Function

Most important serine protease inhibitor in plasma that regulates the blood coagulation cascade (PubMed:15140129, PubMed:15853774). AT-III inhibits thrombin, matriptase-3/TMPRSS7, as well as factors IXa, Xa and XIa (PubMed:15140129). Its inhibitory activity is greatly enhanced in the presence of heparin

Subcellular location

Secreted, extracellular space
Domains and Gene Ontology detail (13)

Gene Ontology

  • Cblood microparticle
  • Cendoplasmic reticulum lumen
  • Cextracellular exosome
  • Cextracellular matrix
  • Cextracellular region
  • Cextracellular space
  • Cplasma membrane
  • Fheparin binding
  • Fidentical protein binding
  • Fprotease binding
  • Fserine-type endopeptidase inhibitor activity
  • Pblood coagulation

464 aa · 53 kDa

Biological roles

Reactome v97

What this protein does, drawn together from its UniProt function, Gene Ontology terms and Reactome pathways.

HaemostasisUniProt · GO · ReactomeProteolysisUniProt · GOKinase signallingReactomeCell adhesionGO
View supporting evidence

Haemostasis

  • ·Most important serine protease inhibitor in plasma that regulates the blood coagulation…
  • ·blood coagulation
  • ·regulation of blood coagulation
  • ·Fibrin formation

Proteolysis

  • ·Most important serine protease inhibitor in plasma that regulates the blood coagulation…
  • ·protease binding

Kinase signalling

  • ·Post-translational protein phosphorylation

Cell adhesion

  • ·extracellular matrix
View underlying pathways (6)

Concepts derived from UniProt GO Reactome — each badge above shows which sources supported that role.

Interaction neighbourhood

STRING v12.0

Proteins with the strongest functional or physical association. Node size and line weight reflect STRING confidence; hover or select a partner to inspect one association.

F2F9F10PLGFGAF12F11F3FGBVTNSERPINC1

10 strongest partners — larger node and heavier line mean higher confidence

Functional and physical associations from STRING v12.0. Only associations with this protein are drawn — partner-to-partner links are not part of this evidence.

Drugs targeting this protein

2

Whether each drug engages this protein directly or through a complex, and how many other targets are recorded for it. Direct binders with few recorded targets are listed first.

Dalteparin
Narrow target profileActivator

Antithrombin-III activator

Direct interaction with this protein · Only this protein recorded as a target

Enoxaparin
Narrow target profileActivator

Antithrombin-III activator

Direct interaction with this protein · Only this protein recorded as a target

ChEMBL mechanism, action type and target identity. Open Targets clinical status and indications.

Translational evidence

Open Targets 26

Why this target matters therapeutically — disease associations, drugs in development, tractability and safety, from Open Targets.

Strongest genetic associations

Human genetic evidence — the most direct causal link between this target and a disease.

Reduced antithrombin III activity0.99

Genetic · overall 0.79

hereditary antithrombin deficiency0.96

Genetic · overall 0.85

Venous thrombosis0.76

Genetic · overall 0.68

blood coagulation disease0.58

Genetic · overall 0.65

venous thromboembolism0.36

Genetic · overall 0.66

Highest-confidence therapeutic associations

Diseases where a drug acting on this target has already reached clinical development.

deep vein thrombosis0.99

Clinical · overall 0.66

pulmonary embolism0.99

Clinical · overall 0.60

atrial fibrillation0.98

Clinical · overall 0.60

myocardial infarction0.98

Clinical · overall 0.60

Recurrent thrombophlebitis0.92

Clinical · overall 0.56

Show all associations
hereditary antithrombin deficiency0.85
Reduced antithrombin III activity0.79
Venous thrombosis0.68
venous thromboembolism0.66
deep vein thrombosis0.66
blood coagulation disease0.65
pulmonary embolism0.60
atrial fibrillation0.60
myocardial infarction0.60
Recurrent thrombophlebitis0.56

Open Targets ranks 1,117 associations for this target and we store the top 10 by aggregated score. The long tail is largely literature co-mention and RNA-expression evidence, not evidence that this target drives those diseases.

Known drugs · 12 total

HEPARIN SODIUMApproval

Venous thrombosis · Thromboembolism · deep vein thrombosis

TINZAPARIN SODIUMApproval

deep vein thrombosis · Recurrent thrombophlebitis · venous thromboembolism

DALTEPARIN SODIUMApproval

deep vein thrombosis · venous thromboembolism · Recurrent thrombophlebitis

FONDAPARINUX SODIUMApproval

deep vein thrombosis · venous thromboembolism · Venous thrombosis

BEMIPARIN SODIUMPhase 3

pulmonary embolism · deep vein thrombosis

FITUSIRANPhase 3

hemophilia · hemophilia A · hemophilia B

NADROPARIN CALCIUMApproval

Recurrent thrombophlebitis · blood coagulation disease · venous thromboembolism

HEPARIN CALCIUMApproval

blood coagulation disease · thrombotic disease · myocardial infarction

DANAPAROID SODIUMApproval

Recurrent thrombophlebitis · Thrombocytopenia

FONDAPARINUXApproval

Recurrent thrombophlebitis · myocardial infarction · angina unstable

Tractability

SM · Structure with LigandSM · High-Quality PocketSM · Druggable FamilyAB · GO CC high confAB · UniProt loc med confAB · UniProt SigP or TMHMMPR · Small Molecule BinderOC · Approved Drug

Safety liabilities

thrombocytopenia

Clinical trials

30

Trials of drugs that target this protein — reached indirectly through those drugs, so a trial listed here studies the drug, not the protein.

COMPLETED · via Enoxaparin · NCT00170378

Show remaining trials (24)

ClinicalTrials.gov via the drug-target graph.

Forefront confidence

Synthesis

Our own weighting of the evidence behind each disease association. Human genetics and clinical evidence count for most; literature co-mention counts for little, because two entities sharing an abstract is not evidence that one drives the other.

Reduced antithrombin III activityWell supported
0.99
agreement 0.871.00
Genetic100%Genetic literaturedup

Open Targets aggregate 0.79 · 1 independent evidence family · 1 not counted as duplicate

hereditary antithrombin deficiencyWell supported
0.97
agreement 0.851.00
Genetic77%Animal model18%Literature5%Genetic literaturedup

Open Targets aggregate 0.85 · 3 independent evidence families · 1 not counted as duplicate

Venous thrombosisWell supported
0.94
agreement 0.851.00
Genetic44%Clinical40%Animal model13%Literature4%

Open Targets aggregate 0.68 · 4 independent evidence families

blood coagulation diseaseWell supported
0.87
agreement 0.770.98
Clinical54%Genetic45%Literature2%

Open Targets aggregate 0.65 · 3 independent evidence families

deep vein thrombosisWell supported
0.84
agreement 0.730.94
Clinical66%Genetic27%Literature7%

Open Targets aggregate 0.66 · 3 independent evidence families

This ranking differs from Open Targets' own: re-weighting moves genetically-evidenced diseases above more heavily co-mentioned ones. The evidence agreement range shows how closely the independent evidence families agree — it is not a statistical confidence interval, and nothing here is fitted to outcome data. Derived from Open Targets evidence types under Forefront weighting; the underlying per-type scores are shown above so the calculation can be checked.

What's happening now

10

Recent activity around this target, drawn from one canonical event stream. Every item is reached through 2 drugs that target this protein, so each event is news about that drug rather than about the protein directly.

  1. New publication2021-02-01
    American Society of Hematology 2021 guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19.

    Blood advances · 2021 · 293 citations · Europe PMC · via Enoxaparin

  2. New publication2020-03-29
    Apixaban for the Treatment of Venous Thromboembolism Associated with Cancer.

    The New England journal of medicine · 2020 · 671 citations · Europe PMC · via Dalteparin

  3. New publication2017-12-12
    Edoxaban for the Treatment of Cancer-Associated Venous Thromboembolism.

    The New England journal of medicine · 2018 · 1,036 citations · Europe PMC · via Dalteparin

  4. Regulatory approval2016-09-15

    Approval: Inhixa (EMA)

    ema · regulatory · ema · via Enoxaparin

  5. New publication2014-06-26
    Predicting the risk of venous thromboembolism in patients hospitalized with heart failure.

    Circulation · 2014 · 44 citations · Europe PMC · via Enoxaparin

  6. New publication2014-04-01
    D-dimer as a predictor of venous thromboembolism in acutely ill, hospitalized patients: a subanalysis of the randomized controlled MAGELLAN trial.

    Journal of thrombosis and haemostasis : JTH · 2014 · 82 citations · Europe PMC · via Enoxaparin

  7. New publication2013-02-01
    Rivaroxaban for thromboprophylaxis in acutely ill medical patients.

    The New England journal of medicine · 2013 · 412 citations · Europe PMC · via Enoxaparin

  8. New publication2012-12-13
    Prediction and prevention of thromboembolic events with enoxaparin in cancer patients with elevated tissue factor-bearing microparticles: a randomized-controlled phase II trial (the Microtec study).

    British journal of haematology · 2013 · 98 citations · Europe PMC · via Enoxaparin

  9. New publication2009-05-04
    Rivaroxaban versus enoxaparin for thromboprophylaxis after total knee arthroplasty (RECORD4): a randomised trial.

    Lancet (London, England) · 2009 · 646 citations · Europe PMC · via Enoxaparin

  10. New publication2003-07-01
    Low-molecular-weight heparin versus a coumarin for the prevention of recurrent venous thromboembolism in patients with cancer.

    The New England journal of medicine · 2003 · 1,599 citations · Europe PMC · via Dalteparin

Objective event titles are shown unmodified; the event kind and significance line are derived from structured fields. Forefront AttentionEvent stream aggregating Europe PMC Regulatory filings ClinicalTrials.gov.