> Trialight public data. Index of pages: https://trialight.com/llms.txt
> Web page: https://trialight.com/data/asset/fazamorexant-fd05b09b-2a6e-43d8-abdf-dee2903191b1
> Record changed: 2026-10-13

# Fazamorexant

Highest phase reached

Phase 3

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314459)

Drug type

Small molecule

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314459)

## Development status

**Listing at source**

Listed

**Highest phase reached**

Phase 3

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314459)

## Names and chemistry

**Drug type**

Small molecule

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314459)

**Drug name**

Fazamorexant

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314459)

**Molecular weight**

432.5

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314459)

**Structure (SMILES)**

Cc1ccc(-c2ncccn2)c(C(=O)N2\[C@H\]3CC\[C@@H\](COc4ccc(F)cn4)\[C@@H\]2CC3)c1

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314459)

### Other names (11)

- fazamorexant
- Fazamorexant
- fazamorexant \[INN\]
- fazamorexant inn
- yzj 1139
- YZJ-1139
- YZJ-1139 10mg
- YZJ-1139 20mg
- YZJ-1139 40mg
- YZJ-1139 60mg
- YZJ-1139 tablets

## Identifiers

**CAS registry numbers**

- 1808918-69-5

**ChEMBL ID**

CHEMBL5314459

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314459)

**InChIKey**

PMJPLAGTPPVSRL-JLMWRMLUSA-N

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314459)

**PubChem compound IDs**

- 156889652

**FDA ingredient codes (UNII)**

- MDH4D7M594

## Regulatory information

### Other regulatory facts

**First in class**

No

**Orphan designation**

No

## Pharmacology

### Drug classification

**Pharmacology name**

fazamorexant

**Type**

Synthetic organic

### Mechanisms of action (2)

- **Action**  
Antagonist

**Action type**  
Antagonist

**Target**  
OX1 receptor

**Gene symbol**  
HCRTR1

**Protein identifier**  
O43613

**Median affinity**

7.7

**Affinity units**  
pIC50
- **Action**  
Antagonist

**Action type**  
Antagonist

**Target**  
OX2 receptor

**Gene symbol**  
HCRTR2

**Protein identifier**  
O43614

**Median affinity**

7.44

**Affinity units**  
pIC50

### Investigated indications

- **Condition**  
Sleep Initiation and Maintenance Disorders

**Highest recorded phase**  
3

**Condition identifier**  
EFO:0004698

**Subject identifier**  
D007319

### Open Targets indications (2)

- **Condition identifier**  
EFO\_0004698

**Highest recorded phase**  
3
- **Condition identifier**  
MONDO\_0013600

**Highest recorded phase**  
3

### Trial references

- NCT05525637  
Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT05525637)

## Chemical properties

**Hydrogen bond acceptors**

5

**Hydrogen bond donors**

0

**Polar surface area**

68.21

**Calculated partition coefficient (ALogP)**

4.45

**Calculated partition coefficient (XLogP)**

4.1

**Prodrug**

No

**Chirality**

Single enantiomer

**Inorganic**

No

**Rule-of-five violations**

0

**Rotatable bonds**

5

**Heavy atoms**

32

**Molecular formula**

C25H25FN4O2

**Monoisotopic mass**

432.19615422

**Natural product**

No

## Related records

### Trials (9)

- A Clinical Study to Evaluate the Drug Interaction Between YZJ-1139 Tablets and Escitalopram Oxalate Tablets
- A Drug-drug Interaction Study of YZJ-1139 Tablets and Ticagrelor Tablets in Healthy Subjects
- A Study to Evaluate the Safety, Tolerability, and Pharmacokinetics of Single and Multiple Doses of YZJ-1139 in Healthy Participants
- Pharmacokinetics and Safety Study of YZJ-1139 in Subjects With Mild, Moderate and Normal Hepatic Impairment
- Pharmacokinetics and Safety Study of YZJ-1139 in Subjects With Severe Renal Impairment and Normal Renal Impairment
- PK/PD Study of YZJ-1139
- [Safety and Efficacy Study of YZJ-1139 in Insomnia Disorder](https://trialight.com/data/trial/safety-and-efficacy-study-of-yzj-1139-in-insomnia-disorder-552a2901-80ee-4a9c-a1f4-dd8278a0f455.md)
- Safety and Efficacy Study of YZJ-1139 in Primary Chronic Insomnia Disorder
- Safety and Efficacy Study of YZJ-1139 Tablets in Insomnia Disorder

### In development for (1)

- [Insomnia](https://trialight.com/data/condition/insomnia-57f6af86-fd71-567b-813f-5867cfd4790c.md) Phase 3

---

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