Zileuton
As of the edition of 20 October 2026, Zileuton is a small molecule: marketed, first approved in 1996 (US); acts on ALOX5; no US protection is listed.
Sources: FDA Orange Book and Purple Book, other approval registers, ClinicalTrials.gov, ChEMBL.
The drug
- Status
- Marketed; latest approval 1996
- Kind
- Small molecule
- Brand name
- Zyflo
- First approved
- 9 December 1996 (US)
- Approvals on record
- 3 in 1 region
- Holder of the most recent approval
- Chiesi
- Registered trials
- 15, 4 stopped early
- Disease areas
- Lungs and airways; Blood and lymph; Cancer; Immune system; Chemically induced; Inherited and neonatal
US protection
No US protection is listed.
The FDA registers list no drug-substance patent or exclusivity that counts for this drug.
This is the US only.
Companies that need a new molecule because of this drug
1 company on route B because of this drug.
Companies on route B for this drug
In the product1 company is on route B because of Zileuton.
See the 1 company on route B for this drug, with the facts behind eachRequest access. Nothing is shown until you do.
Target
| Gene | Protein | UniProt |
|---|---|---|
| ALOX5 | Polyunsaturated fatty acid 5-lipoxygenase | P09917 |
Registered trials
| Phase | Trials | Completed | Active | Stopped early |
|---|---|---|---|---|
| Phase 1 | 4 | 2 | 0 | 2 |
| Phase 2 | 9 | 7 | 0 | 1 |
| Phase 4 | 2 | 1 | 0 | 1 |
| All trials | 15 |
Who has held its approvals
| Company | Role | Years |
|---|---|---|
| Critical Therapeutics | Later holder and Lead sponsor of trials | 2004 to now |
| Chiesi | Acquired holder | 2014 to now |
| Abbott | Originator | 1996 to 2014 |