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NCT01733316 · ClinicalTrials.gov registry record · Phase 3
Open-Label, Safety and Superior Effectiveness Study of Cysteamine Bitartrate Delayed-Release Capsules (RP103) in Cystinosis
A Phase 3 study, sponsored by Amgen.
- Completed
- Registry status
- Phase 3
- Development phase
- 41
- Enrollment target
NCT01733316: Completed Phase 3 study, sponsored by Amgen.
NCT01733316 is a Phase 3 study that has completed, run by Amgen. The registered enrollment target is 41 participants, below the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (95% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT01733316, a Phase 3 study, has completed, sponsored by Amgen.
- COMPLETED
- Registry status
- Phase 3
- Development phase
- 41 participants
- Enrollment target
Study Summary
The purpose of this study is to gather information about the effectiveness (how well it works to treat cystinosis) and safety of a new form of cysteamine bitartrate called RP103, compared to the already-approved drug cystinosis patients are taking called Cystagon®. In cystinosis, the body builds up cystine. When taken regularly, the active ingredient of Cystagon® (cysteamine bitartrate) reduces cystine in the body. RP103 has the same active ingredient as Cystagon® and is designed to reduce cystine in a similar way that Cystagon® does. To decide if RP103 is better than Cystagon®, the study will look at two types of blood tests. One test is pharmacodynamics (PD), which measures the amount of white blood cell (WBC) cystine after taking study drug. WBC cystine is a laboratory test used to find out if cysteamine bitartrate is reducing cystine levels in the body. The second test is pharmacokinetics (PK), which measures the amount of cysteamine in the blood after taking the drug. RP103 is different from Cystagon®: Instead of the cysteamine bitartrate being absorbed from the stomach, RP103 is designed to be absorbed from the small intestine. This may make the effects of the drug last longer, so that it can be taken twice a day instead of four times a day like Cystagon®. Some cystinosis patients have bad breath (halitosis) when they take Cystagon®. Study participants who experience bad breath with Cystagon® will be asked if they would like to participate in an optional "halitosis substudy" to investigate this issue by collecting some extra PK blood samples.
Primary Outcome
The primary analysis of WBC cystine was performed using the natural log transformed WBC cystine level; the log transformation is a normalizing transformation. For each participant, the difference between the morning and corresponding non-morning log WBC cystine value (non-morning minus morning) at each monthly visit during the Cystagon® phase (Months 1, 2, and 3) was computed and these differences were averaged. The average difference between morning and non-morning log WBC cystine value was sim
Interventions
- DRUG RP103
- DRUG Cystagon®
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 41 participants |
| Start Date | 2013-01-31 |
| Est. Completion | 2017-07-10 |
| Phase | Phase 3 |
What the finished NCT01733316 record still lists
NCT01733316 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 41 participants, a relatively small participant target, below the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (95% lower).
The record links to 0 conditions, and to 2 interventions - of which RP103 is the first listed.
NCT01733316 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT01733316 about?
NCT01733316 is a clinical study titled "Open-Label, Safety and Superior Effectiveness Study of Cysteamine Bitartrate Delayed-Release Capsules (RP103) in Cystinosis". The purpose of this study is to gather information about the effectiveness (how well it works to treat cystinosis) and safety of a new form of cysteamine bitartrate called RP103, compared to the already-approved drug cystinosis patients are taking called Cystagon®. In cystinosis, the body builds up...
What is the current status of trial NCT01733316?
This trial is currently completed. It is a Phase 3 study. The enrollment target is 41 participants. The study started on 2013-01-31. Estimated completion is 2017-07-10.
What interventions are being tested in trial NCT01733316?
The interventions under investigation include: RP103 (DRUG), Cystagon® (DRUG).
Who is sponsoring clinical trial NCT01733316?
This trial is sponsored by Amgen, which has 558 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT01733316's enrollment target sits among peer trials
41 1877th of 2000 higher than 123 of 2,000 other Phase 3 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 3 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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