Summary
Cysteamine Hydrochloride has reached the approved stage (maximum clinical phase 4) for at least one indication, so its use in Cystic Fibrosis would be drug repurposing rather than first-in-human development. This does not mean it is approved for Cystic Fibrosis. ClinicalTrials.gov lists 2 registered trials linking Cysteamine Hydrochloride to Cystic Fibrosis: 2 have completed. The most advanced is Phase 2 (NCT03000348). It plans or enrolled 91 participants. Registration activity spans 2014 to 2016. No published literature item is linked to Cysteamine Hydrochloride and Cystic Fibrosis in the OSMF database yet, so the record rests on registry entries alone. Registry entries describe intent to study, not outcomes.
The RepurpOS disease-intelligence file for Cystic Fibrosis ranks 50 candidate therapeutics from Open Targets, ChEMBL, DGIdb and PubMed; only a minority carry direct clinical evidence, and this page covers one of those. Spontaneous remission context recorded for the condition: Progressive lung function decline; no spontaneous remission; historically median survival 30 years; now >50 years with CFTR modulators for eligible genotypes.
Evidence table
| Evidence tier | A · Strong |
|---|---|
| Evidence score | 26.0 (trials 6.0, literature 0.0, tier 15, approved bonus 5.0) |
| Registered trials | 2 total: 0 recruiting, 0 active / not yet recruiting, 2 completed, 0 other |
| Linked publications | 0 |
| Agent type | Drug (Small molecule) |
| Development stage (any indication) | Approved |
| Mechanism / class | Not recorded |
| Data sources | DGIdb |
| Linked via biomarker / target | CFTR |
How the evidence score is calculated
- Each registered trial scores by status (recruiting / active / enrolling 3, completed 2.5, not yet recruiting 2, unknown 1, terminated / withdrawn / suspended 0.5) plus a phase bonus (phase 3-4 +2, phase 2 +1, phase 1 +0.5). The trial component is capped at 30.
- Each literature item scores by design (Cochrane review 5, meta-analysis 4, systematic review 3, RCT 3, clinical trial publication 2, curated reference 1.5, other PubMed record 1). The literature component is capped at 30.
- The existing evidence tier adds 15 (A / Strong), 10 (B / Moderate), 5 (C / Preliminary) or 0 (D / Anecdotal).
- Agents approved for any indication (max clinical phase 4) add 5, because an approved agent has an established safety profile that lowers the barrier to repurposing trials.
- The score ranks what has been studied, not what works. It does not read effect sizes or directions of effect.
Registered clinical trials
| NCT ID | Title | Status | Phase | Enrolment |
|---|---|---|---|---|
| NCT03000348 | A Study of the Dosing, Efficacy, and Safety of Oral Cysteamine in Adult Patients With Cystic Fibrosis Exacerbations 2016 | completed | Phase 2 | 91 |
| NCT02212431 | First Study of Oral Cysteamine in Cystic Fibrosis 2014 | completed | PHASE1, PHASE2 | 10 |
Published literature
No publication is linked to this pair yet.
Mechanism and notes
No mechanism of action is recorded for this pair in the source databases.
OSMF's existing evidence tier for this pair is A (Strong), derived from the strength of the disease association recorded in DGIdb, in this case via the biomarker or target CFTR. The tier describes how well the drug-disease link is documented, not how well the drug works.
Frequently asked questions
Is Cysteamine Hydrochloride approved for Cystic Fibrosis?
Cysteamine Hydrochloride has reached the approved stage (maximum clinical phase 4) for at least one indication, so its use in Cystic Fibrosis would be drug repurposing rather than first-in-human development. This does not mean it is approved for Cystic Fibrosis. Approval status for the specific indication should always be confirmed with the relevant regulator and prescribing information.
Is Cysteamine Hydrochloride in clinical trials for Cystic Fibrosis?
ClinicalTrials.gov lists 2 registered trials linking Cysteamine Hydrochloride to Cystic Fibrosis: 2 have completed. The most advanced is Phase 2 (NCT03000348). It plans or enrolled 91 participants. Registration activity spans 2014 to 2016.
What does the evidence show for Cysteamine Hydrochloride in Cystic Fibrosis?
Cysteamine Hydrochloride has 2 completed registered trials for Cystic Fibrosis but no linked publication, which usually means results are unpublished, pending, or not yet matched to this record. OSMF's existing evidence tier for this pair is A (Strong), derived from the strength of the disease association recorded in DGIdb, in this case via the biomarker or target CFTR. The tier describes how well the drug-disease link is documented, not how well the drug works.
Cite this page
Data: ClinicalTrials.gov, PubMed, Open Targets, ChEMBL, DGIdb and the OSMF therapeutic agent database. Last updated 2026-07-06. Page built 2026-10-07.