Protein / target

Amine oxidase [flavin-containing] B

MAOBP27338Homo sapiensSwiss-Prot
Clinically validated
Therapeutic maturity
15
Approved medicines
19
Clinical trials
Small-molecule tractable
Druggability
Approved Drug

Protein at a glance

Biological role

Primary methylamine oxidase activity

Strongest disease association

hypertensive disorder

Genetic evidence · score 0.07

Therapeutic maturity

Clinically validated target

15 approved medicines against this target

Druggability

Small molecule

Open Targets tractability · Approved Drug

Clinical development

15 approved · 1 in clinical development

19 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

Catalyzes the oxidative deamination of primary and some secondary amines such as neurotransmitters, and exogenous amines including the tertiary amine, neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), with concomitant reduction of oxygen to hydrogen peroxide and participates in the metabolism of neuroactive and vasoactive amines in the central nervous system and peripheral tissues (PubMed:11049757, PubMed:11134050, PubMed:20493079, PubMed:8316221, PubMed:8665924). Preferentially degrades benzylamine and phenylethylamine (PubMed:11049757, PubMed:11134050, PubMed:20493079, PubMed:8316221, PubMed:8665924)

Subcellular location

Mitochondrion outer membrane
Domains and Gene Ontology detail (11)

Gene Ontology

  • Cmitochondrial envelope
  • Cmitochondrial outer membrane
  • Cmitochondrion
  • Felectron transfer activity
  • Fmonoamine oxidase activity
  • Fprimary methylamine oxidase activity
  • Pdopamine catabolic process
  • Phydrogen peroxide biosynthetic process
  • Pphenylethylamine catabolic process
  • Pserotonin metabolic process
  • Psubstantia nigra development

520 aa · 59 kDa · 2 isoforms

Biological roles

Reactome v97

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

Metabolic enzyme activityGO
View supporting evidence

Metabolic enzyme activity

  • ·serotonin 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.

COMTLRTOMTDDCDBHAOC2ALDH2AOC3AOC1PRKNAOX1MAOB

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

1

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.

Selegiline
Narrow target profileApprovedInhibitor

Monoamine oxidase B inhibitor

Appears in clinical studies involving Parkinson disease, major depressive disorder, cocaine dependence, depressive disorder

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.

hypertensive disorder0.07

Genetic · overall 0.38

Highest-confidence therapeutic associations

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

Parkinson disease0.99

Clinical · overall 0.63

major depressive disorder0.95

Clinical · overall 0.59

depressive disorder0.81

Clinical · overall 0.50

Hypertension0.61

Clinical · overall 0.37

melancholia0.61

Clinical · overall 0.37

Highest overall evidence

Remaining associations by Open Targets' aggregated evidence score.

neurodegenerative disease0.31

Pathway

cocaine dependence0.29

Clinical

neuropathic pain0.28

Clinical

Borderline personality disorder0.26

Clinical

Show all associations
Parkinson disease0.63
major depressive disorder0.59
depressive disorder0.50
hypertensive disorder0.38
Hypertension0.37
melancholia0.37
neurodegenerative disease0.31
cocaine dependence0.29
neuropathic pain0.28
Borderline personality disorder0.26

Open Targets ranks 474 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 · 18 total

PHENELZINE SULFATEApproval

prostate cancer · breast cancer

SELEGILINEApproval

Parkinson disease · major depressive disorder · cocaine dependence

MEBANAZINEUnknown
PARGYLINEApproval

hypertensive disorder · Hypertension · muscular dystrophy

PHENOXYPROPAZINEUnknown
ISOCARBOXAZIDApproval

major depressive disorder · depressive disorder

PHENELZINEApproval

depressive disorder · major depressive disorder

RASAGILINE MESYLATEApproval

Parkinson disease · Parkinson disease · Parkinson disease

IPRONIAZIDApproval

major depressive disorder

RALFINAMIDEPhase 3

neuropathic pain

Tractability

SM · Approved DrugSM · Structure with LigandSM · High-Quality LigandSM · High-Quality PocketSM · Druggable FamilyAB · UniProt SigP or TMHMMPR · Database UbiquitinationPR · Half-life DataPR · Small Molecule Binder

Safety liabilities

diarrhoeahallucinationsdyskinesiadizzinessHypertension

Clinical trials

19

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

Show remaining trials (13)

COMPLETED · via Selegiline · NCT00000188

COMPLETED · via Selegiline · NCT00000337

COMPLETED · via Selegiline · NCT01495195

COMPLETED · via Selegiline · NCT00000336

COMPLETED · via Selegiline · NCT00218517

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.

Parkinson diseaseWell supported
0.78
agreement 0.620.93
Clinical84%Literature16%

Open Targets aggregate 0.63 · 2 independent evidence families

major depressive disorderModerately supported
0.73
agreement 0.580.89
Clinical91%Literature9%

Open Targets aggregate 0.59 · 2 independent evidence families

depressive disorderModerately supported
0.63
agreement 0.470.78
Clinical93%Literature7%

Open Targets aggregate 0.50 · 2 independent evidence families

hypertensive disorderLimited support
0.50
agreement 0.390.60
Clinical85%Genetic13%Literature2%

Open Targets aggregate 0.38 · 3 independent evidence families

HypertensionLimited support
0.46
agreement 0.310.62
Clinical97%Literature3%

Open Targets aggregate 0.37 · 2 independent evidence families

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

2

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

  1. New publication2010-09-01
    Failure to improve cigarette smoking abstinence with transdermal selegiline + cognitive behavior therapy.

    Addiction (Abingdon, England) · 2010 · 26 citations · Europe PMC · via Selegiline

  2. New publication1997-04-01
    A controlled trial of selegiline, alpha-tocopherol, or both as treatment for Alzheimer's disease. The Alzheimer's Disease Cooperative Study.

    The New England journal of medicine · 1997 · 1,344 citations · Europe PMC · via Selegiline

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.