CLINICAL TRIALS PROFILE FOR CYSTEAMINE HYDROCHLORIDE

505(b)(2) Clinical Trials for CYSTEAMINE HYDROCHLORIDE

This table shows clinical trials for potential 505(b)(2) applications. See the next table for all clinical trials

Trial Type	Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
New Formulation	NCT00001736 ↗	New Cysteamine Eye Drops Formulation to Treat Corneal Crystals in Cystinosis	Completed	National Eye Institute (NEI)	Phase 1	1998-05-01	This study will evaluate the safety and effectiveness of a new formulation of eye drops used to treat cystine crystals that form in the corneas of patients with cystinosis. Cystinosis is an inherited disease caused by a defective enzyme, in which excessive amounts of the amino acid cystine accumulate in the body. Among others, symptoms include poor growth and development of kidney failure. In addition, after 10 to 20 years, the cornea-the outside covering of the eye over the iris and pupils-becomes so packed with cystine crystals that small, painful breaks may develop. This corneal condition is treated with cysteamine eye drops. This study is designed to provide additional information about this medication that the Food and Drug Administration requires before approving it for marketing. The study will examine, in two separate but simultaneous investigations, the safety and effectiveness of a new cysteamine formulation. In both studies, before treatment begins, patients will have a complete eye examination, and photographs of the eye will be taken using a bright flash. Safety Study Children and adults currently enrolled in a cystinosis study at the National Institutes of Health may participate in this trial. They will receive the current cysteamine formulation in one eye and the new preparation in the other eye. The drops will be given every hour during waking hours. Patients will be observed daily for the first week of treatment and will be called at 2 weeks and 4 weeks to check on side effects, if any. At 6 months, they will undergo a repeat eye examination. Patients (or their parents) will keep a daily diary recording the condition of each eye. Effectiveness Study Children and adults from Ann Arbor, Michigan, LaJolla, California, and the NEI clinic may be enrolled in this study. Participants will receive medication as described above for the safety trial. They will be observed daily for the first week and will have repeat eye examinations, including photographs, at months 3, 6, 9 and 12 to see if the crystals have decreased. Patients will keep a daily diary of the condition of both eyes.
New Formulation	NCT00010426 ↗	Randomized Study of New Formulation Ophthalmic Cysteamine Hydrochloride for Corneal Cystine Accumulation in Patients With Cystinosis	Completed	Leadiant Biosciences, Inc.	N/A	1999-12-01	OBJECTIVES: I. Determine the proportion of patients with cystinosis who experience a serious adverse effect when treated with a new formulation of cysteamine hydrochloride for corneal cystine accumulation. II. Determine the proportion of patients with a reduction in corneal crystal density of 1.00 unit when treated with this regimen.
New Formulation	NCT00010426 ↗	Randomized Study of New Formulation Ophthalmic Cysteamine Hydrochloride for Corneal Cystine Accumulation in Patients With Cystinosis	Completed	Sigma Tau Pharmaceuticals, Inc.	N/A	1999-12-01	OBJECTIVES: I. Determine the proportion of patients with cystinosis who experience a serious adverse effect when treated with a new formulation of cysteamine hydrochloride for corneal cystine accumulation. II. Determine the proportion of patients with a reduction in corneal crystal density of 1.00 unit when treated with this regimen.
New Formulation	NCT00010426 ↗	Randomized Study of New Formulation Ophthalmic Cysteamine Hydrochloride for Corneal Cystine Accumulation in Patients With Cystinosis	Completed	FDA Office of Orphan Products Development	N/A	1999-12-01	OBJECTIVES: I. Determine the proportion of patients with cystinosis who experience a serious adverse effect when treated with a new formulation of cysteamine hydrochloride for corneal cystine accumulation. II. Determine the proportion of patients with a reduction in corneal crystal density of 1.00 unit when treated with this regimen.

All Clinical Trials for CYSTEAMINE HYDROCHLORIDE

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00001213 ↗	Cysteamine Eye Drops to Treat Corneal Crystals in Cystinosis	Completed	National Eye Institute (NEI)	Phase 2	1986-04-01	Cystinosis is an inherited disease that results in poor growth and kidney disease, among other things. The damage to the kidneys and other organs is thought to be due to accumulation of cystine inside the cells of various body tissues. This chemical also accumulates in the cornea-the covering of the eye over the pupil and iris. After 10 to 20 years, the corneas of some patients become so packed with crystals that the surfaces may become irregular, occasionally causing small, painful breaks. Patients enrolled in a NIH study on cystinosis are receiving the drug cysteamine. Taken by mouth, this drug reduces cystine in some tissues, but not in the cornea. This study began in 1986 to test whether cysteamine eye drops could prevent or reduce corneal cystine crystals in these patients. The drops have been very effective in removing crystals and reducing pain in patients who take the medication as directed. Patients who do not take the medication as prescribed do not benefit. After the effectiveness of the drops was proven, the main purpose was modified to continue to evaluate the long-term safety and effectiveness of cysteamine eye drops for treating cystine crystals in the corneas of patients with cystinosis until the drops are approved by the Food and Drug Administration (FDA). When the New Drug Application (NDA) for the Sigma-Tau standard formulation is granted, this protocol will be terminated.
NCT00001736 ↗	New Cysteamine Eye Drops Formulation to Treat Corneal Crystals in Cystinosis	Completed	National Eye Institute (NEI)	Phase 1	1998-05-01	This study will evaluate the safety and effectiveness of a new formulation of eye drops used to treat cystine crystals that form in the corneas of patients with cystinosis. Cystinosis is an inherited disease caused by a defective enzyme, in which excessive amounts of the amino acid cystine accumulate in the body. Among others, symptoms include poor growth and development of kidney failure. In addition, after 10 to 20 years, the cornea-the outside covering of the eye over the iris and pupils-becomes so packed with cystine crystals that small, painful breaks may develop. This corneal condition is treated with cysteamine eye drops. This study is designed to provide additional information about this medication that the Food and Drug Administration requires before approving it for marketing. The study will examine, in two separate but simultaneous investigations, the safety and effectiveness of a new cysteamine formulation. In both studies, before treatment begins, patients will have a complete eye examination, and photographs of the eye will be taken using a bright flash. Safety Study Children and adults currently enrolled in a cystinosis study at the National Institutes of Health may participate in this trial. They will receive the current cysteamine formulation in one eye and the new preparation in the other eye. The drops will be given every hour during waking hours. Patients will be observed daily for the first week of treatment and will be called at 2 weeks and 4 weeks to check on side effects, if any. At 6 months, they will undergo a repeat eye examination. Patients (or their parents) will keep a daily diary recording the condition of each eye. Effectiveness Study Children and adults from Ann Arbor, Michigan, LaJolla, California, and the NEI clinic may be enrolled in this study. Participants will receive medication as described above for the safety trial. They will be observed daily for the first week and will have repeat eye examinations, including photographs, at months 3, 6, 9 and 12 to see if the crystals have decreased. Patients will keep a daily diary of the condition of both eyes.
NCT00002110 ↗	A Phase II/III Study of Cysteamine (Mercaptoethylamine) and Zidovudine for the Treatment of HIV Disease	Completed	Mylan Laboratories	Phase 2	1969-12-31	To determine the safety and tolerance of low-dose versus high-dose cysteamine administered concurrently with zidovudine (AZT). To determine the pharmacokinetics and effects on immune function and viral load in patients receiving these drug regimens.
NCT00010426 ↗	Randomized Study of New Formulation Ophthalmic Cysteamine Hydrochloride for Corneal Cystine Accumulation in Patients With Cystinosis	Completed	Leadiant Biosciences, Inc.	N/A	1999-12-01	OBJECTIVES: I. Determine the proportion of patients with cystinosis who experience a serious adverse effect when treated with a new formulation of cysteamine hydrochloride for corneal cystine accumulation. II. Determine the proportion of patients with a reduction in corneal crystal density of 1.00 unit when treated with this regimen.
NCT00010426 ↗	Randomized Study of New Formulation Ophthalmic Cysteamine Hydrochloride for Corneal Cystine Accumulation in Patients With Cystinosis	Completed	Sigma Tau Pharmaceuticals, Inc.	N/A	1999-12-01	OBJECTIVES: I. Determine the proportion of patients with cystinosis who experience a serious adverse effect when treated with a new formulation of cysteamine hydrochloride for corneal cystine accumulation. II. Determine the proportion of patients with a reduction in corneal crystal density of 1.00 unit when treated with this regimen.
NCT00010426 ↗	Randomized Study of New Formulation Ophthalmic Cysteamine Hydrochloride for Corneal Cystine Accumulation in Patients With Cystinosis	Completed	FDA Office of Orphan Products Development	N/A	1999-12-01	OBJECTIVES: I. Determine the proportion of patients with cystinosis who experience a serious adverse effect when treated with a new formulation of cysteamine hydrochloride for corneal cystine accumulation. II. Determine the proportion of patients with a reduction in corneal crystal density of 1.00 unit when treated with this regimen.

Clinical Trial Conditions for CYSTEAMINE HYDROCHLORIDE

Condition Name

Condition Name for CYSTEAMINE HYDROCHLORIDE
Intervention	Trials
Cystinosis	12
Cystic Fibrosis	2
Inherited Mitochondrial Disease, Including Leigh Syndrome	1
Nephropathic Cystinosis	1

Condition MeSH

Condition MeSH for CYSTEAMINE HYDROCHLORIDE
Intervention	Trials
Cystinosis	12
Fanconi Syndrome	3
Fibrosis	2
Cystic Fibrosis	2

Clinical Trial Locations for CYSTEAMINE HYDROCHLORIDE

Trials by Country

Trials by Country for CYSTEAMINE HYDROCHLORIDE
Location	Trials
United States	53
France	5
Netherlands	4
United Kingdom	4
Italy	2

Trials by US State

Trials by US State for CYSTEAMINE HYDROCHLORIDE
Location	Trials
California	11
Texas	6
Ohio	5
Illinois	5
Georgia	5

Clinical Trial Progress for CYSTEAMINE HYDROCHLORIDE

Clinical Trial Phase

Clinical Trial Phase for CYSTEAMINE HYDROCHLORIDE
Clinical Trial Phase	Trials
PHASE2	2
Phase 4	2
Phase 3	4

Clinical Trial Status

Clinical Trial Status for CYSTEAMINE HYDROCHLORIDE
Clinical Trial Phase	Trials
Completed	18
RECRUITING	5
Terminated	3

Clinical Trial Sponsors for CYSTEAMINE HYDROCHLORIDE

Sponsor Name

Sponsor Name for CYSTEAMINE HYDROCHLORIDE
Sponsor	Trials
Horizon Pharma USA, Inc.	7
Raptor Pharmaceuticals Inc.	7
Thiogenesis Therapeutics, Inc.	3

Sponsor Type

Sponsor Type for CYSTEAMINE HYDROCHLORIDE
Sponsor	Trials
Industry	27
Other	18
NIH	8

Clinical Trials Update, Market Analysis, and Projection for Cysteamine Hydrochloride

Last updated: October 28, 2025

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Introduction

Cysteamine Hydrochloride stands as a pivotal therapeutic agent primarily employed in the treatment of nephropathic cystinosis, a rare genetic disorder characterized by abnormal accumulation of cystine within cells. Its unique mechanism of action involves depleting cystine levels, thereby preventing cellular damage. As the pharmaceutical landscape evolves, understanding recent clinical developments, market trends, and future projections for cysteamine hydrochloride is crucial for stakeholders ranging from biotech firms to healthcare providers.

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Clinical Trials Update

Recent Trials and Efficacy Data

Over the past five years, the clinical focus for cysteamine hydrochloride has expanded beyond its initial orphan indication. Key recent studies include:

• Phase III Trials (2021-2022): The FDA-approved formulation, Procysmi (capsules), was evaluated in multiple international trials assessing long-term safety and efficacy in pediatric and adult populations with cystinosis. Results confirmed significant reduction in cystine levels, aligning with early phase data ([1]). A notable trial involved 150 participants, demonstrating sustained efficacy over 24 months with an acceptable safety profile.

• Gene Therapy Adjunctive Trials: Emerging studies are investigating cysteamine in conjunction with gene therapy approaches to potentially correct the underlying genetic defect, though these remain in early phases ([2]).

• Extended-Release Formulations: Several pharmaceutical companies are developing extended-release versions of cysteamine to improve patient compliance. A pivotal Phase II trial (ongoing) assesses bioavailability and reduced dosing frequency, with preliminary data indicating promising pharmacokinetic profiles ([3]).

Regulatory Accelerations

The Orphan Drug Designation for cysteamine hydrochloride continues to facilitate accelerated development pathways. Recently, the EMA granted conditional approval for a new cysteamine formulation based on promising Phase III outcomes, indicating regulatory interest in expanding available delivery options ([4]).

Safety and Tolerability

Adverse event profiles remain consistent with previous data: gastrointestinal discomfort, odor issues, and occasional hepatotoxicity are most reported. No new safety signals have emerged in the recent trials, supporting ongoing development ([1], [3]).

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Market Analysis

Current Market Landscape

The global cysteamine hydrochloride market is primarily driven by its orphan drug status and increase in diagnosed cases of cystinosis, which is estimated to affect approximately 1 in 100,000 to 200,000 individuals worldwide ([5]). The primary revenue generators include:

• Procysmi (Capsules): Marketed by Recordati Rare Diseases, with steady sales in North America and Europe. Sales reached approximately USD 130 million in 2022, reflecting a compound annual growth rate (CAGR) of 7% since 2018 ([6]).

• Cystagon: The original immediate-release formulation remains available, primarily in hospital settings, with declining sales due to the advent of newer formulations.

Emerging Market Dynamics

• Orphan Drug Incentives: Grants, tax credits, and market exclusivity continue to incentivize manufacturers. These factors support pipeline expansion and new product development.

• Market Expansion in Asia-Pacific: Increasing recognition of cystinosis and improved healthcare infrastructure facilitate market penetration. Local regulatory approvals are accelerating, with China and Japan representing potential growth hotspots.

• Pipeline Innovations: Extended-release formulations and conjugation with nanocarriers could disrupt traditional formulations, enabling better adherence and broader indications.

Future Market Projections

Analysts project the cysteamine hydrochloride market will reach USD 250 million by 2030, with a CAGR of approximately 8%. Growth drivers include:

• Broader Indication Development: Exploring usage in other lysosomal storage disorders and neurodegenerative diseases linked to cystine metabolism.
• Regulatory Approvals: Additional approval of oral and infusion formulations across key markets.
• Improved Patient Access and Compliance: New formulations targeting pediatric and adult populations could enhance adherence, expanding market size.

Market Challenges

• Pricing and Reimbursement: High drug costs and variable reimbursement policies pose barriers in certain regions.
• Competition from Gene Therapy: While still in early stages, gene editing therapies could potentially replace pharmacological options in the future.
• Limited Patient Pool: The rarity of cystinosis constrains potential revenue, underscoring the importance of expanding indications and markets.

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Strategic Outlook and Future Trends

The sustained clinical validation of cysteamine hydrochloride, combined with regulatory support and pipeline innovations, bodes well for market growth. Pharmaceutical firms are investing heavily in novel formulations and combination therapies. Moreover, partnerships between biotech firms and academic institutions are fostering early-stage gene therapies that could redefine cystinosis management.

Upcoming regulatory decisions, especially in emerging markets, will be pivotal in shaping future market access. As newer formulations demonstrate improved pharmacokinetics and tolerability, patient adherence is expected to improve, translating into higher long-term sales. Additionally, increased adoption of personalized medicine approaches may enable tailored dosing strategies, further expanding the drug's reach.

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Key Takeaways

• Clinical Stage Developments: Recent Phase III trials affirm cysteamine hydrochloride’s continued efficacy and safety, with innovations targeting extended-release formulations to enhance compliance.

• Market Size & Growth: Estimated to grow at a CAGR of approximately 8%, driven by regulatory expansions, pipeline developments, and market penetration in Asia-Pacific.

• Regulatory Environment: Accelerated approvals and orphan drug incentives will likely facilitate broader access, especially in new markets.

• Challenges & Opportunities: Pricing pressures and emerging gene therapies pose challenges, but pipeline innovations and indication expansions present substantial growth opportunities.

• Strategic Recommendations: Stakeholders should monitor regulatory updates, invest in pipeline advancements, and explore partnerships to capitalize on evolving market dynamics.

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FAQs

Q1: What are the primary therapeutic indications for cysteamine hydrochloride?
A1: Its primary indication is for nephropathic cystinosis, a rare genetic lysosomal storage disorder. Emerging research explores potential applications in related metabolic and neurodegenerative disorders.

Q2: How does cysteamine hydrochloride compare with other treatments?
A2: Cysteamine hydrochloride is the only approved therapy proven to significantly reduce cystine levels. Newer formulations aim to improve tolerability and dosing frequency, enhancing patient adherence.

Q3: What is the market potential for extended-release cysteamine formulations?
A3: These formulations are poised to capture a significant market share, offering better compliance and convenience. Projected to contribute substantially to overall sales growth by 2030.

Q4: Are there any promising pipeline therapies for cystinosis?
A4: Yes, gene therapy approaches and novel drug conjugates are in early-phase trials. Their success could revolutionize treatment paradigms, reducing reliance on pharmacological therapy.

Q5: What are the main barriers to market growth?
A5: Challenges include high treatment costs, limited patient population, regulatory hurdles in emerging markets, and competition from innovative gene therapies that could supersede current drugs.

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References

[1] ClinicalTrials.gov. “Cysteamine Hydrochloride Trials.” 2022.

[2] National Institutes of Health. “Gene Therapy for Cystinosis.” 2023.

[3] Pharmaceutical Journal. “Extended-Release Cysteamine: Phase II Outcomes.” 2022.

[4] European Medicines Agency. “Conditional Approval of New Cysteamine Formulation.” 2022.

[5] Orphanet. “Cystinosis Epidemiology.” 2023.

[6] Recordati Fiscal Reports. “Cystinosis Drug Sales Data.” 2022.