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Protein / target

Integrin alpha-IIb

Encoded byITGA2BP08514Homo sapiensSwiss-Prot
Clinically validated
Therapeutic maturity
4
Approved medicines
Open Targets target-level
View by indication →
30
Clinical trials
Small-molecule tractable
Druggability
Approved Drug

Protein at a glance

Biological role

Extracellular matrix binding

Strongest disease association

Autosomal dominant macrothrombocytopenia

Via encoding gene ITGA2B · Genetic evidence · score 0.85

Therapeutic position

Established drug target

Small molecules and antibodies

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 overview

Integrin alpha-IIb/beta-3 (ITGA2B:ITGB3) is a receptor for fibronectin, fibrinogen, plasminogen, prothrombin, thrombospondin and vitronectin.

View complete UniProt function annotation

Integrin alpha-IIb/beta-3 (ITGA2B:ITGB3) is a receptor for fibronectin, fibrinogen, plasminogen, prothrombin, thrombospondin and vitronectin. It recognizes the sequence R-G-D in a wide array of ligands. It recognizes the sequence H-H-L-G-G-G-A-K-Q-A-G-D-V in fibrinogen gamma chain (By similarity). Following activation integrin alpha-IIb/beta-3 brings about platelet/platelet interaction through binding of soluble fibrinogen (PubMed:9111081). This step leads to rapid platelet aggregation which physically plugs ruptured endothelial cell surface (By similarity). Integrin ITGA2B:ITGB3 is also the receptor of erythrocyte-specific ICAM4 ligand involved in heterotypic cell-cell adhesion between erythrocytes and activated platelets (PubMed:12477717)

Subcellular location

Cell membrane
Domains and Gene Ontology detail (21)

Gene Ontology

  • Cblood microparticle
  • Ccell surface
  • Cexternal side of plasma membrane
  • Cextracellular exosome
  • Cfocal adhesion
  • Cintegrin alphaIIb-beta3 complex
  • Cplasma membrane
  • Cplatelet alpha granule membrane
  • Fextracellular matrix binding
  • Ffibrinogen binding
  • Fidentical protein binding
  • Fmetal ion binding

1039 aa · 113 kDa · 3 isoforms

Biological roles

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

Cell adhesionUniProt · GOHaemostasisUniProt · GO
View supporting evidence

Cell adhesion

  • ·Integrin alpha-IIb/beta-3 (ITGA2B:ITGB3) is a receptor for fibronectin, fibrinogen, plas…
  • ·extracellular matrix binding
  • ·cell-cell adhesion
  • ·cell-cell adhesion mediated by integrin

Haemostasis

  • ·Integrin alpha-IIb/beta-3 (ITGA2B:ITGB3) is a receptor for fibronectin, fibrinogen, plas…
  • ·platelet alpha granule membrane
  • ·fibrinogen binding

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

Approved medicines with mapped indications

2 medicines · 4 areas

Approved therapies targeting this protein, grouped by what they are approved to treat — the disease-first view of the medicines below. Relationships come from the canonical approved-indication graph (ChEMBL phase-4), the same source as the drug cards.

Angina, Unstable2 medicines
Thrombosis2 medicines
Acute Coronary Syndrome1 medicine
Myocardial Infarction1 medicine

4 medicines meet Open Targets' target-level approved-medicine definition; the 2 shown here are those on this page with a canonical approved disease indication in the graph. Approved indications from ChEMBL (phase-4), via the canonical drug→disease graph.

Drugs targeting this protein

2

How approved and investigational drugs engage this protein — mechanism and action type, direct vs complex targeting, and how broadly each acts across other targets. A drug-first view (the section above groups the approved ones disease-first); direct binders with few recorded targets are listed first.

eptifibatide
ApprovedInhibitor

Integrin alpha-IIb/beta-3 inhibitor

Indicated for Acute Coronary Syndrome, Angina, Unstable, Myocardial Infarction, Thrombosis

Acts on a complex — shared with ITGB3 · 1 of 2 recorded protein targets — narrow recorded profile

abciximab
ApprovedInhibitor

Integrin alpha-IIb/beta-3 inhibitor

Indicated for Angina, Unstable, Thrombosis

Acts on a complex — shared with ITGB3 · 1 of 3 recorded protein targets — narrow recorded profile

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

Translational evidence

Open Targets 26

Why this target matters therapeutically, strongest evidence first. Disease associations are gene-level (via the gene that encodes this protein) and open into the full confidence synthesis; the development universe, tractability and safety annotations are target-level, from Open Targets.

Strongest disease associations · via encoding gene ITGA2B

Gene-level evidence surfaced through the gene ITGA2Bthat encodes this protein — not a direct protein–disease relationship. Ranked by Forefront's causal-directness weighting, so genetically- and clinically-evidenced diseases lead over ones that merely share the literature.

Autosomal dominant macrothrombocytopenia
0.90Well supported

Genetic evidence dominant · Open Targets 0.69

Myocardial Infarction
0.70Moderately supported

Clinical evidence dominant · Open Targets 0.57

Acute Coronary Syndrome
0.67Moderately supported

Clinical evidence dominant · Open Targets 0.54

Neoplasms
0.42Preliminary

Pathway evidence dominant · Open Targets 0.60 · no direct causal or clinical evidence

Noonan syndrome
0.35Preliminary

Pathway evidence dominant · Open Targets 0.53 · no direct causal or clinical evidence

View evidence synthesis (5)
Autosomal dominant macrothrombocytopeniaWell supported
0.90
agreement 0.781.00
Genetic72%Animal model27%Literature1%Genetic literaturedup

Open Targets aggregate 0.69 · 3 independent evidence families · 1 not counted as duplicate

Myocardial InfarctionModerately supported
0.70
agreement 0.540.85
Clinical97%Literature4%

Open Targets aggregate 0.57 · 2 independent evidence families

Acute Coronary SyndromeModerately supported
0.67
agreement 0.520.83
Clinical97%Literature3%

Open Targets aggregate 0.54 · 2 independent evidence families

NeoplasmsPreliminary
0.42
agreement 0.240.60
Pathway88%Literature12%

Open Targets aggregate 0.60 · 2 independent evidence families · no direct causal or clinical evidence

Noonan syndromePreliminary
0.35
agreement 0.120.57
Pathway100%

Open Targets aggregate 0.53 · 1 independent evidence family · no direct causal or clinical evidence

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 per-type scores above show the calculation.

Show all associations
Autosomal dominant macrothrombocytopenia0.69
Neoplasms0.60
Myocardial Infarction0.57
Acute Coronary Syndrome0.54
Noonan syndrome0.53
Cardiomyopathy, Hypertrophic0.51
Costello syndrome0.50

Drug development

6 compounds recorded · 4 approved · 2 in clinical development

Open Targets' development universe — every compound recorded against the target at any stage, not all approved medicines. Distinct from the 2 drugs that target this protein in Forefront's canonical graph (2 with a mapped approved indication, shown above): these count different sets and are not a subset relation.

View all recorded compounds (6)
EPTIFIBATIDEApproval
TIROFIBANApproval
TADOCIZUMABPhase 2
ZALUNFIBANPhase 3
ABCIXIMABApproval
TIROFIBAN HYDROCHLORIDEApproval

Open Targets known-drugs universe. Drug name and highest clinical stage only — the disease relationship is NOT read from this slice (it carries trial-context noise); approved indications come from the canonical graph above.

Tractability

Small moleculesStrong

Approved Drug and Structure with Ligand support this modality.

AntibodiesStrong

Advanced Clinical and GO CC high conf support this modality.

Protein degradersEmerging

Feasibility evidence (half-life data and small molecule binder) — no clinical-stage drug of this modality recorded.

Other modalitiesStrong

Approved Drug support this modality.

View underlying tractability evidence (12)
SM · Approved DrugSM · Structure with LigandSM · High-Quality LigandSM · High-Quality PocketSM · Druggable FamilyAB · Advanced ClinicalAB · GO CC high confAB · UniProt SigP or TMHMMAB · Human Protein Atlas locPR · Half-life DataPR · Small Molecule BinderOC · Approved Drug

Raw Open Targets tractability assessment buckets, by modality.

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. Ranked by active status, then clinical phase and recency, and spread across the targeting drugs.

View all trials (26)

COMPLETED · via eptifibatide · NCT00111566

COMPLETED · via eptifibatide · NCT00638976

ClinicalTrials.gov via the drug-target graph.

What's happening now

6

Recent therapeutic activity around this target — regulatory actions, clinical trials and safety signals for 2 drugs that target this protein, plus publications where such a drug is a genuine subject. Every item is reached indirectly through the drug, not the protein itself; incidental mentions (a paper that merely measures a drug) and press items are excluded.

  1. Withdrawn from market2026-01-01

    Market withdrawal: Integrilin (EMA)

    ema · market · ema · via eptifibatide

  2. Regulatory approval2016-01-11

    Approval: Eptifibatide Accord (EMA)

    ema · regulatory · ema · via eptifibatide

  3. New publication2015-08-04
    Combined Approach to Lysis Utilizing Eptifibatide and Recombinant Tissue-Type Plasminogen Activator in Acute Ischemic Stroke-Full Dose Regimen Stroke Trial.

    Stroke · 2015 · 52 citations · Europe PMC · via eptifibatide

  4. New publication2009-03-01
    Abbreviated infusion of eptifibatide after successful coronary intervention The BRIEF-PCI (Brief Infusion of Eptifibatide Following Percutaneous Coronary Intervention) randomized trial.

    Journal of the American College of Cardiology · 2009 · 40 citations · Europe PMC · via eptifibatide

  5. New publication2007-11-21
    Emergency administration of abciximab for treatment of patients with acute ischemic stroke: results of an international phase III trial: Abciximab in Emergency Treatment of Stroke Trial (AbESTT-II).

    Stroke · 2008 · 234 citations · Europe PMC · via abciximab

  6. New publication1999-04-01
    Sustained suppression of ischemic complications of coronary intervention by platelet GP IIb/IIIa blockade with abciximab: one-year outcome in the EPILOG trial. Evaluation in PTCA to Improve Long-term Outcome with abciximab GP IIb/IIIa blockade.

    Circulation · 1999 · 72 citations · Europe PMC · via abciximab

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.