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Protein / target

Vitamin K epoxide reductase complex subunit 1

Encoded byVKORC1Q9BQB6Homo sapiensSwiss-Prot
Clinically validated
Therapeutic maturity
6
Approved medicines
Open Targets target-level
View by indication →
8
Clinical trials
Small-molecule tractable
Druggability
Approved Drug

Protein at a glance

Biological role

Vitamin-K-epoxide reductase (warfarin-insensitive)

Strongest disease association

Hereditary combined deficiency of vitamin K-dependent clotting factors

Via encoding gene VKORC1 · Genetic literature evidence · score 0.80

Therapeutic position

Established drug target

Small molecules

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

Involved in vitamin K metabolism.

View complete UniProt function annotation

Involved in vitamin K metabolism. Catalytic subunit of the vitamin K epoxide reductase (VKOR) complex which reduces inactive vitamin K 2,3-epoxide to active vitamin K. Vitamin K is required for the gamma-carboxylation of various proteins, including clotting factors, and is required for normal blood coagulation, but also for normal bone development

Subcellular location

Endoplasmic reticulum membrane
Domains and Gene Ontology detail (11)

Gene Ontology

  • Cendoplasmic reticulum
  • Cendoplasmic reticulum lumen
  • Cendoplasmic reticulum membrane
  • Fquinone binding
  • Fvitamin-K-epoxide reductase (warfarin-insensitive) activity
  • Fvitamin-K-epoxide reductase (warfarin-sensitive) activity
  • Pblood coagulation
  • Pbone development
  • Ppeptidyl-glutamic acid carboxylation
  • Pvitamin K metabolic process
  • Pxenobiotic metabolic process

163 aa · 18 kDa · 3 isoforms

Biological roles

Reactome v97

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

HaemostasisUniProt · GOMetabolic enzyme activityGO
View supporting evidence

Haemostasis

  • ·Involved in vitamin K metabolism. Catalytic subunit of the vitamin K epoxide reductase (…
  • ·blood coagulation

Metabolic enzyme activity

  • ·vitamin K metabolic process
  • ·xenobiotic metabolic process
View underlying pathways (1)

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.

GGCXCYP2C9CYP4F2VKORC1…NQO1CYP2C19PROS1MGPF2ABCC6VKORC1

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.

Approved medicines with mapped indications

1 medicine · 1 area

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.

Thrombosis1 medicine

6 medicines meet Open Targets' target-level approved-medicine definition; the 1 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

1

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.

Acenocoumarol
Narrow target profileApprovedInhibitor

Vitamin k epoxide reductase complex subunit 1 isoform 1 inhibitor

Indicated for Thrombosis

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

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 VKORC1

Gene-level evidence surfaced through the gene VKORC1 that 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.

Thrombosis
0.77Well supported

Clinical evidence dominant · Open Targets 0.60

Atrial Fibrillation
0.76Well supported

Clinical evidence dominant · Open Targets 0.61

Venous Thromboembolism
0.76Well supported

Genetic evidence dominant · Open Targets 0.45

Hereditary combined deficiency of vitamin K-dependent clotting factors
0.70Moderately supported

Genetic literature evidence dominant · Open Targets 0.72

Pulmonary Embolism
0.69Moderately supported

Clinical evidence dominant · Open Targets 0.56

View evidence synthesis (5)
ThrombosisWell supported
0.77
agreement 0.660.87
Clinical74%Genetic26%Literature0%

Open Targets aggregate 0.60 · 3 independent evidence families

Atrial FibrillationWell supported
0.76
agreement 0.600.91
Clinical95%Literature5%

Open Targets aggregate 0.61 · 2 independent evidence families

Venous ThromboembolismWell supported
0.76
agreement 0.650.86
Genetic54%Clinical45%Literature1%

Open Targets aggregate 0.45 · 3 independent evidence families

Hereditary combined deficiency of vitamin K-dependent clotting factorsModerately supported
0.70
agreement 0.570.84
Genetic literature79%Animal model21%Geneticdup

Open Targets aggregate 0.72 · 2 independent evidence families · 1 not counted as duplicate

Pulmonary EmbolismModerately supported
0.69
agreement 0.530.84
Clinical97%Literature3%

Open Targets aggregate 0.56 · 2 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 per-type scores above show the calculation.

Show all associations
Hereditary combined deficiency of vitamin K-dependent clotting factors0.72
vitamin K-dependent clotting factors, combined deficiency of, type 20.72
Atrial Fibrillation0.61
Thrombosis0.60
Pulmonary Embolism0.56
Myocardial Infarction0.52
Stroke0.50
Venous Thromboembolism0.45

Drug development

7 compounds recorded · 6 approved · 1 in clinical development

Open Targets' development universe — every compound recorded against the target at any stage, not all approved medicines. Distinct from the 1 drug that targets this protein in Forefront's canonical graph (1 with a mapped approved indication, shown above): these count different sets and are not a subset relation.

View all recorded compounds (7)
PHENPROCOUMONApproval
PHENINDIONEApproval
TECARFARINPhase 3
DICUMAROLApproval
ACENOCOUMAROLApproval
WARFARINApproval
WARFARIN SODIUMApproval

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.

AntibodiesEmerging

Feasibility evidence (uniprot sigp or tmhmm) — no clinical-stage drug of this modality recorded.

Protein degradersEmerging

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

View underlying tractability evidence (7)
SM · Approved DrugSM · Structure with LigandSM · High-Quality LigandSM · Druggable FamilyAB · UniProt SigP or TMHMMPR · Half-life DataPR · Small Molecule Binder

Raw Open Targets tractability assessment buckets, by modality.

Safety-related annotations

over-anticoagulationClinPGxhemorrhageClinPGxHemorrhageClinPGxadverse eventsClinPGxbleedingClinPGx

Terms indexed against this target in Open Targets' safety data, with their datasource. These are annotations, not causal claims: the direction of effect (whether activation or inhibition is implicated), species and evidence strength are not captured here, so an entry does not mean that modulating this target is known to cause that condition.

Clinical trials

8

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.

ClinicalTrials.gov via the drug-target graph.

What's happening now

1

Recent therapeutic activity around this target — regulatory actions, clinical trials and safety signals for a drug that targets 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. 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 Acenocoumarol

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.