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NCT00641537 · ClinicalTrials.gov registry record · Phase 3
CLARITY Extension Study
A Phase 3 study, sponsored by EMD Serono Research & Development Institute.
- Completed
- Registry status
- Phase 3
- Development phase
- 867
- Enrollment target
NCT00641537: Completed Phase 3 study, sponsored by EMD Serono Research & Development Institute.
NCT00641537 is a Phase 3 study that has completed, run by EMD Serono Research & Development Institute. The registered enrollment target is 867 participants, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (12% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT00641537, a Phase 3 study, has completed, sponsored by EMD Serono Research & Development Institute.
- COMPLETED
- Registry status
- Phase 3
- Development phase
- 867 participants
- Enrollment target
Study Summary
The purpose of this extension trial was to further evaluate the safety and tolerability of oral cladribine in subjects who have previously completed treatment within Trial 25643 (CLARITY). This trial also explored clinical benefit of prolonged 192-week versus 96-week treatment.
Primary Outcome
Hematologic and hepatic toxicity was assessed using Common Terminology Criteria for Adverse Events v 3.0 (CTCAE). Hematologic and hepatic function included absolute lymphocyte count (ALC), hemoglobin level, white blood cell (WBC) count, absolute neutrophil count (ANC), platelets, alanine transaminase (ALT), aspartate transaminase (AST) and bilirubin. According to CTCAE v3.0: Grade 1=mild, Grade 2=moderate, Grade 3=severe, Grade 4=life threatening or disabling and Grade 5=Death.
Interventions
- DRUG Placebo
- DRUG Cladribine
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 867 participants |
| Start Date | 2008-02-29 |
| Est. Completion | 2011-12-31 |
| Phase | Phase 3 |
What the finished NCT00641537 record still lists
NCT00641537 is an interventional study that assigns participants to a tested intervention. The registered 867 participants enrollment target is mid-sized for trials with a published cap, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (12% higher).
The record links to 0 conditions, and to 2 interventions - of which Placebo is the first listed.
NCT00641537 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT00641537 about?
NCT00641537 is a clinical study titled "CLARITY Extension Study". The purpose of this extension trial was to further evaluate the safety and tolerability of oral cladribine in subjects who have previously completed treatment within Trial 25643 (CLARITY). This trial also explored clinical benefit of prolonged 192-week versus 96-week treatment.
What is the current status of trial NCT00641537?
This trial is currently completed. It is a Phase 3 study. The enrollment target is 867 participants. The study started on 2008-02-29. Estimated completion is 2011-12-31.
What interventions are being tested in trial NCT00641537?
The interventions under investigation include: Placebo (DRUG), Cladribine (DRUG).
Who is sponsoring clinical trial NCT00641537?
This trial is sponsored by EMD Serono Research & Development Institute, which has 81 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT00641537's enrollment target sits among peer trials
867 376th of 2000 higher than 1,625 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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