Cysteine
As of the edition of 20 October 2026, Cysteine is a small molecule: marketed, first approved in 1979 (FR).
Sources: FDA Orange Book and Purple Book, other approval registers, ClinicalTrials.gov, ChEMBL.
The drug
- Status
- Marketed; latest approval 2011
- Kind
- Small molecule
- Brand name
- Elcys
- First approved
- 16 November 1979 (FR)
- Approvals on record
- 8 in 4 regions
- Holder of the most recent approval
- Exela Pharma Sciences; 4 holders in all
- Registered trials
- 5, 0 stopped early
- Disease areas
- Nutrition and metabolism; Inherited and neonatal; Digestive system; Nervous system; Skin and connective tissue; Bones, joints and muscles
US protection
No US approval on record.
With no US approval on record there are no listed US patents or exclusivities.
This is the US only.
Registered trials
| Phase | Trials | Completed | Active | Stopped early |
|---|---|---|---|---|
| Phase not stated | 3 | 3 | 0 | 0 |
| Phase 1 | 1 | 1 | 0 | 0 |
| Phase 3 | 1 | 1 | 0 | 0 |
| All trials | 5 |
Who has held its approvals
| Company | Role | Years |
|---|---|---|
| Pfizer | Acquired holder and Earlier holder | 1986 to now |
| Baxter Healthcare | Applicant and Acquired holder | 1997 to now |
| Exela Pharma Sciences | Later holder | 2019 to now |