> Trialight public data. Index of pages: https://trialight.com/llms.txt
> Web page: https://trialight.com/data/asset/idrx-42-aa864735-bc4f-4b08-99e6-7d050c360d98
> Record changed: 2026-10-13

# IDRX-42

Highest phase reached

Phase 1

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314917)

Drug type

Small molecule

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314917)

## Development status

**Listing at source**

Listed

**Highest phase reached**

Phase 1

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314917)

## Names and chemistry

**Drug type**

Small molecule

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314917)

**Drug name**

IDRX-42

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314917)

**Molecular weight**

508.63

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314917)

**Structure (SMILES)**

Cn1cc(-c2ccc(CNc3cc(-c4cnc5cc(OCCCN6CCCC6)ccn45)ncn3)cc2)cn1

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314917)

### Other names (9)

- idrx 42
- Idrx-42
- IDRX-42
- m 4205
- M-4205
- velzatinib
- Velzatinib
- velzatinib \[INN\]
- velzatinib inn

## Identifiers

**CAS registry numbers**

- 2590556-80-0

**ChEMBL ID**

CHEMBL5314917

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314917)

**InChIKey**

LVMAULGVWBINFP-UHFFFAOYSA-N

Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/chembl/explore/compound/CHEMBL5314917)

**PubChem compound IDs**

- 155587867

**FDA ingredient codes (UNII)**

- Y6UHU32G5Z

## Regulatory information

### Other regulatory facts

**First in class**

No

**Orphan designation**

No

## Pharmacology

### Drug classification

**Pharmacology name**

velzatinib

**Type**

Synthetic organic

### Mechanisms of action (8)

- **Action type**  
Inhibitor

**Target**  
colony stimulating factor 1 receptor

**Gene symbol**  
colony stimulating factor 1 receptor
- **Action type**  
Inhibitor

**Target**  
KIT proto-oncogene, receptor tyrosine kinase

**Gene symbol**  
KIT proto-oncogene, receptor tyrosine kinase
- **Action type**  
Inhibitor

**Target**  
platelet derived growth factor receptor alpha

**Gene symbol**  
platelet derived growth factor receptor alpha
- **Action type**  
Inhibitor

**Target**  
platelet derived growth factor receptor beta

**Gene symbol**  
platelet derived growth factor receptor beta
- **Action**  
Inhibition

**Action type**  
Inhibitor

**Target**  
colony stimulating factor 1 receptor

**Gene symbol**  
CSF1R

**Protein identifier**  
P07333

**Median affinity**

8.26

**Affinity units**  
pIC50
- **Action**  
Inhibition

**Action type**  
Inhibitor

**Target**  
platelet derived growth factor receptor beta

**Gene symbol**  
PDGFRB

**Protein identifier**  
P09619

**Median affinity**

8.59

**Affinity units**  
pIC50
- **Action**  
Inhibition

**Action type**  
Inhibitor

**Target**  
KIT proto-oncogene, receptor tyrosine kinase

**Gene symbol**  
KIT

**Protein identifier**  
P10721

**Median affinity**

7.36

**Affinity units**  
pIC50
- **Action**  
Inhibition

**Action type**  
Inhibitor

**Target**  
platelet derived growth factor receptor alpha

**Gene symbol**  
PDGFRA

**Protein identifier**  
P16234

**Median affinity**

7.3

**Affinity units**  
pIC50

### Open Targets indications

- **Condition identifier**  
MONDO\_0011719

**Highest recorded phase**  
3

## Chemical properties

**Hydrogen bond acceptors**

9

**Hydrogen bond donors**

1

**Polar surface area**

85.4

**Calculated partition coefficient (ALogP)**

4.67

**Calculated partition coefficient (XLogP)**

4.3

**Prodrug**

No

**Chirality**

Achiral

**Inorganic**

No

**Rule-of-five violations**

1

**Rotatable bonds**

10

**Heavy atoms**

38

**Molecular formula**

C29H32N8O

**Monoisotopic mass**

508.26990767

**Natural product**

No

## Evidence counts

**Recorded assays**

164

**Active assays**

10

### Active assay types

- Confirmatory

## Biological measurements

These details could not be displayed.

## Related records

### Trials (4)

- A Study of IDRX-42 (GSK6042981) Versus (vs) Sunitinib in Participants With Gastrointestinal Stromal Tumors After Imatinib Therapy
- A Study of Velzatinib in Participants With Metastatic and/or Unresectable GIST After Imatinib, Sunitinib, Regorafenib, and Pimitespib
- A Study to Investigate Velzatinib Compared With Imatinib in Adult Participants With Previously Untreated Metastatic and/or Unresectable Gastrointestinal Stromal Tumors (StrateGIST Frontline)
- [First-in-human Study of IDRX-42 in Participants With Metastatic and/or Unresectable Gastrointestinal Stromal Tumors](https://trialight.com/data/trial/first-in-human-study-of-idrx-42-in-participants-with-586a3587-f558-492e-9647-ff8481728f1b.md)

---

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