Hydroxyurea
As of the edition of 20 October 2026, Hydroxyurea is a small molecule: marketed, first approved in 1979 (CA); acts on RRM2; no US protection of its own is listed.
Sources: FDA Orange Book and Purple Book, other approval registers, ClinicalTrials.gov, ChEMBL.
The drug
- Status
- Marketed; latest approval 2007
- Kind
- Small molecule
- Brand name
- Hydrea
- First approved
- 31 December 1979 (CA)
- Approvals on record
- 14 in 7 regions
- Holder of the most recent approval
- Nova; 9 holders in all
- Registered trials
- 171, 21 stopped early
- Disease areas
- Blood and lymph; Inherited and neonatal; Cancer; Nervous system; Immune system; Infections
US protection
No US protection of its own is listed.
The FDA registers list no drug-substance patent or exclusivity of its own that counts for this drug.
Nova holds a later exclusivity on its own new formulation or combination product, ending 2031; it does not protect the original 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 Hydroxyurea.
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 |
|---|---|---|
| RRM2 | Ribonucleoside-diphosphate reductase subunit M2 | P31350 |
Registered trials
| Phase | Trials | Completed | Active | Stopped early |
|---|---|---|---|---|
| Phase not stated | 24 | 14 | 8 | 0 |
| Phase 1 | 25 | 14 | 6 | 3 |
| Phase 2 | 85 | 50 | 16 | 13 |
| Phase 3 | 29 | 17 | 1 | 4 |
| Phase 4 | 8 | 6 | 1 | 1 |
| All trials | 171 |
Who has held its approvals
| Company | Role | Years |
|---|---|---|
| Cheplapharm Arzneimittel | Applicant | 1979 to now |
| Theravia | Applicant and Lead sponsor of trials | 2007 to now |
| Nova | Later holder and Lead sponsor of trials | 2019 to now |
| Lipomed | Later holder | 2019 to now |
| Theravia Pharma | Acquired holder | 2023 to now |
| Waylis Therapeutics | Acquired holder | 2025 to now |
| Bristol Myers Squibb | Applicant and Lead sponsor of trials |