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Completed Phase 3 Interventional Results available

CLARITY Extension Study

ClinicalTrials.gov ID: NCT00641537

Public ClinicalTrials.gov record NCT00641537. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Jul 22, 2026, 4:03 PM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

A Phase IIIb, Double-Blind, Placebo-Controlled, Multicenter, Parallel Group, Extension Trial to Evaluate the Safety and Tolerability of Oral Cladribine in Subjects With Relapsing-Remitting Multiple Sclerosis Who Have Completed Trial 25643 (CLARITY)

Study identification

NCT ID
NCT00641537
Recruitment status
Completed
Study type
Interventional
Phase
Phase 3
Lead sponsor
EMD Serono Research & Development Institute, Inc.
Industry
Enrollment
867 participants

Conditions and interventions

Interventions

  • Cladribine Drug
  • Placebo Drug

Drug

Eligibility (public fields only)

Age range
18 Years to 65 Years
Sex
All
Healthy volunteers
Healthy volunteers not accepted

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Feb 28, 2008
Primary completion
Dec 30, 2011
Completion
Dec 30, 2011
Last update posted
Dec 6, 2020

2008 – 2011

United States locations

U.S. sites
17
U.S. states
13
U.S. cities
17
Facility City State ZIP Site status
Research Site Boulder Colorado
Research Site Atlanta Georgia
Research Site Chicago Illinois
Research Site Northbrook Illinois
Research Site Baltimore Maryland
Research Site Ann Arbor Michigan
Research Site Henderson Nevada
Research Site Newark New Jersey
Research Site Charlotte North Carolina
Research Site Durham North Carolina
Research Site Columbus Ohio
Research Site Oklahoma City Oklahoma
Research Site Tulsa Oklahoma
Research Site Medford Oregon
Research Site Seattle Washington
Research Site Tacoma Washington
Research Site Charleston West Virginia

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

Non-U.S. locations

This page focuses on the U.S. directory. The official record also lists 99 non-U.S. sites.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT00641537, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Dec 6, 2020 · Synced Jul 22, 2026

Related: full search, browse by condition, browse by drug or therapy, browse by sponsor, browse by U.S. city.

Open the official record

The complete protocol, eligibility criteria, and contact information for NCT00641537 live on ClinicalTrials.gov.

View official ClinicalTrials.gov record →