opioid receptor Agonists
17 drugsAbout opioid receptor
Opioid receptors are a class of G protein-coupled receptors (GPCRs) found throughout the central nervous system (CNS) that are crucial for pain management and mediate various physiological effects. Activation of these receptors by endogenous ligands or drugs leads to analgesia, but also other effects.
Human genetic studies provide strong validation for opioid receptors as therapeutic targets, with variants in OPRM1 linked to opioid use disorder (score 0.86) and skeletal abnormalities (score 0.80). Gain-of-function variants are protective against opioid use disorder, suggesting that activation-based therapies may be beneficial.
Seventeen FDA-approved small molecule drugs target opioid receptors, including ZIMHI, NALOXONE HYDROCHLORIDE, and REZENOPY. These drugs are primarily used for conditions beyond CNS disorders, with 16 drugs categorized within "Other" therapeutic areas.
opioid receptor Genetic Evidence Strong
Genetic evidence strongly supports opioid receptors as a therapeutic target, with a maximum score of 0.86.
Strong genetic support increases the likelihood of clinical success, suggesting further investment in this target is warranted.
💡 Why activation?
- • Gain-of-function variants reduce disease risk — enhancing activity may help
- • 100% directional consistency across 1 traits
- • Strong signal in psychiatric disorder pathways
Cross-Disease Effects
Trade-off: LowDirection of Effect
100% alignedEvidence Across Diseases
14 totalGWAS and other genetic studies link OPRM1 to 14 diseases.
Activating this target may be therapeutic
🔗 Colocalization Evidence 20 strong
max H4: 1.00eQTL/pQTL signals for OPRM1 colocalize with these GWAS traits, providing causal evidence that gene expression changes drive disease risk.
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 opioid receptor Drugs
Nine companies have approved drugs targeting opioid receptors, with DIFGEN PHARMS, ZMI PHARMA, and Viatris among the top players.
The competitive landscape is moderately concentrated, indicating potential for new entrants with differentiated products.
| Drug | Company | Approved | Indications |
|---|---|---|---|
| FENTANYL-62 | Viatris | 2005 | 6 |
| FENTANYL-50 | NOVEN | 2005 | 4 |
| FENTANYL-75 | NOVEN | 2005 | 4 |
| FENTANYL-25 | NOVEN | 2005 | 4 |
| FENTANYL CITRATE PRESERVATIVE FREE | Pfizer | 1991 | 4 |
| FENTANYL-37 | Viatris | 2005 | 4 |
| FENTANYL-12 | Viatris | 2005 | 4 |
| FENTANYL-87 | Viatris | 2005 | 4 |
| KLOXXADO | Hikma | 2021 | 3 |
| REXTOVY | AMPHASTAR PHARMS INC | 2023 | 3 |
| LYBALVI | ALKERMES | 2021 | 3 |
| ZIMHI | ZMI PHARMA | 2021 | 3 |
| REZENOPY | SCIENTURE | 2024 | 3 |
| SUFENTA PRESERVATIVE FREE | RISING | 1984 | 1 |
opioid receptor Drug Modality Landscape
Modalities
Routes of Administration
opioid receptor is amenable to small molecule drugs, with oral options available for convenient dosing.
The modality landscape is saturated with small molecules, suggesting an opportunity for novel modalities like antibodies or biologics.
opioid receptor Clinical Trials 664 trials
Phase 1-4 trials started in 2008 or later that test an FDA-approved drug acting on opioid receptor. Source: ClinicalTrials.gov. How we count
Completion by Phase
| Phase | Total | Completed | Stopped | Active | Completion |
|---|---|---|---|---|---|
| Phase 1 | 93 | 74 | 7 | 12 | 91% |
| Phase 2 | 125 | 86 | 22 | 16 | 80% |
| Phase 3 | 137 | 87 | 20 | 29 | 81% |
| Phase 4 | 309 | 206 | 47 | 55 | 81% |
Top Sponsors
By Modality
Top Conditions
Top Drugs
opioid receptor Drug Approval Timeline (1968 - 2024)
Short-term pain during anesthesia (premedication, inducti...
The first drug targeting opioid receptors was approved in 1968, with the most recent approval in 2024, spanning 57 years.
The long approval history suggests a mature market, but recent approvals indicate continued innovation and unmet needs.
Pro Intelligence Preview
Deep insights for drug target analysis
Competitive Landscape
- • 10 companies competing
- • Market share by company
Full Drug Portfolio
- • All 17 approved drugs
- • Approval dates & indications
Genetic Validation
- • Full genetic evidence table
- • Effect sizes & directions
Approval Timeline
- • Full 17-drug timeline
- • First-of-modality markers
Clinical Trials Analysis
- • Sponsors: 422 (67 companies)
- • Completion rates by condition
Full summary • All drugs • Genetic evidence • Trials • Timeline
How We Count Trials
- Trials: phase 1-4 interventional trials on ClinicalTrials.gov that started in 2008 or later and test an FDA-approved drug acting on opioid receptor. A trial counts if an approved drug acting on opioid receptor is in any arm, including as a comparator, and a trial that tests two such drugs counts once. Trials that test only unapproved drugs are not counted. A trial listed as phase 1/2 counts as phase 1, and phase 2/3 as phase 2.
- Active: recruiting, not yet recruiting, enrolling by invitation, or active and no longer recruiting.
- Completion rate: of the trials that have ended, the share marked Completed rather than Terminated or Withdrawn. Completed means the trial ended as planned; it does not mean the drug worked. Suspended trials are not counted as ended.
- Stopped: terminated or withdrawn. Trials stop for many reasons, including slow enrolment and business decisions, not only safety or efficacy.
- Sponsors: the lead sponsor of each trial. Companies are the sponsors ClinicalTrials.gov classes as industry; the rest are universities, hospitals, cooperative groups, government bodies and individuals.