MAO Inhibitors
3 drugsAbout MAO
Monoamine oxidase (MAO) regulates neurotransmitters like serotonin, norepinephrine, and dopamine in the brain. It has two isoforms, MAO-A and MAO-B, which differ in substrate specificity and tissue distribution.
MAO is a therapeutic target with strong genetic support (max score 0.88) linking MAOA to diseases like Brunner syndrome. Loss-of-function variants are associated with increased risk, suggesting activation may be beneficial.
Three FDA-approved small molecule drugs target MAO, including PARNATE and EMSAM, all indicated for CNS disorders. These drugs highlight the clinical relevance of MAO inhibition.
Strategic Insights
ℹ️ How we calculate- White space opportunity in Major Depressive Disorder (MDD) with only 1 trials.
Human Genetic Evidence Strong
MAOA has strong genetic support with a max score of 0.88 linking it to Brunner syndrome.
Strong genetic support suggests MAO activation strategies may have a higher probability of clinical success.
💡 Why activation?
- • Loss-of-function variants increase disease risk (OR > 1) — restoring function may help
- • 100% directional consistency across 3 traits
- • Strong signal in nutritional or metabolic disease, genetic, familial or congenital disease pathways
Cross-Disease Effects
Trade-off: LowDirection of Effect
100% alignedEvidence Across Diseases
8 totalGWAS and other genetic studies link MAOA to 8 diseases.
Loss-of-function causes disease; activation may help
Loss-of-function causes disease; activation may help
Understanding these scores
Association Score (0-1): Combines all evidence types (genetic, literature, drugs, animal models). Higher = more evidence linking target to disease. This is a ranking heuristic, not a confidence score.
L2G Score: Open Targets uses a machine learning model (Locus-to-Gene) to predict which gene is causal at each GWAS locus. L2G=0.5 means ~50% probability of being the causal gene. Only associations with L2G > 0.05 are included.
Odds Ratio (OR): From gene burden studies (UK Biobank, AstraZeneca PheWAS). Measures how loss-of-function variants affect disease risk. OR<1 = protective (inhibiting target may help), OR>1 = risk (losing function causes disease).
Beta (β): Effect size for continuous traits. β<0 = protective, β>0 = risk.
Clinical Translation (~1.8x): Based on Nelson et al. 2015: drug targets with genetic evidence have ~2x higher success rates in clinical trials. We estimate: Strong support (score ≥0.7) → ~1.8x, Moderate (0.3-0.7) → ~1.3x, Weak → baseline.
Colocalization (H4): Tests whether a GWAS signal and an eQTL/pQTL signal share the same causal variant. H4 is the posterior probability that both traits are associated AND share a causal variant. H4 > 0.8 = strong evidence that gene expression/protein levels drive disease risk. This links genetic variation → gene expression → disease, supporting the target-disease connection.
Top Drugs
Three companies, including ADVANZ PHARMA and SOMERSET, have approved MAO-targeting drugs.
The limited number of players suggests relatively low barriers to entry in the MAO inhibitor market.
Drug Modality Landscape
Modalities
Routes of Administration
MAO is amenable to small molecule drugs, with oral options available for convenient dosing.
Exploring alternative modalities like antibodies or gene therapies could offer a competitive advantage.
Clinical Trials 38 trials
Completion by Phase
| Phase | Total | Completed | Failed | Active | Completion |
|---|---|---|---|---|---|
| Phase 1 | 14 | 11 | 0 | 3 | 100% |
| Phase 2 | 12 | 11 | 1 | 0 | 92% |
| Phase 3 | 6 | 3 | 3 | 0 | 50% |
| Phase 4 | 6 | 4 | 2 | 0 | 67% |
Top Sponsors
By Modality
Top Conditions
Drug Approval Timeline (1961 - 2006)
The first MAO-targeting drug was approved in 1961, with the most recent approval in 2006.
The long gap since the last approval suggests a potential for innovation and new market entrants.
Pro Intelligence Preview
Deep insights for drug target analysis
Competitive Landscape
- • 3 companies competing
- • Market share by company
Full Drug Portfolio
- • All 3 approved drugs
- • Approval dates & indications
Genetic Validation
- • Full genetic evidence table
- • Effect sizes & directions
Approval Timeline
- • Full 3-drug timeline
- • First-of-modality markers
Clinical Trials Analysis
- • Competition: High (15 sponsors)
- • White space: 10 underexplored indications
- • Success rates by condition
Full summary • All drugs • Genetic evidence • Trials • Timeline
How We Calculate These Metrics
Target Attractiveness Score
A 0-100 score based on trial activity, sponsor diversity, and completion rates. Calculated from 22 clinical trials targeting MAO.
Completion rate: Percentage of trials that reached their planned endpoint. Trials terminated early, withdrawn, or suspended are not counted—these often indicate safety issues, lack of efficacy, or strategic pivots.
- Highly Attractive (80+): High trial activity, many sponsors, strong completion rates
- Attractive (60-79): Good trial activity and validation
- Moderate (40-59): Moderate interest from sponsors
- Low (under 40): Limited trial activity or validation concerns
Strategic Insights
Auto-generated insights based on trial analytics including competition intensity, white space opportunities, modality shifts, and failure patterns. We analyze trial sponsors, phases, indications, and outcomes.
Risk Signals
- High Competition: Many sponsors competing for this target (may reduce market opportunity)
- High Failure Risk: Low trial completion rates suggest development challenges
- Low Validation: Limited trial activity or poor outcomes indicate uncertain viability
- White Space Available: Underexplored indications present opportunities