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A Safety and Efficacy Study of Oral Cladribine in Subjects With Relapsing-remitting Multiple Sclerosis (RRMS)

A Phase III, Randomized, Double-blind, Three-arm, Placebo-controlled, Multi-center Study to Evaluate the Safety and Efficacy of Oral Cladribine in Subjects With Relapsing-remitting Multiple Sclerosis (RRMS)

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00213135
Acronym
CLARITY
Enrollment
1326
Registered
2005-09-21
Start date
2005-04-30
Completion date
2008-11-30
Last updated
2014-02-07

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Multiple Sclerosis, Relapsing-Remitting

Brief summary

The purpose of the study is to determine if cladribine tablets are a safe and effective treatment for relapsing-remitting multiple sclerosis (RRMS).

Detailed description

This is a randomized, double-blind, three-arm, placebo-controlled, multi-center study. The study includes a pre-study evaluation period (up to 28 days prior to the start of treatment); an initial treatment period from Week 1 to 48; and a re-treatment period during Week 49 to 96. During the initial treatment period (Week 1 to 48), eligible subjects are equally randomized by a central randomization system to receive either a) cladribine at a low dose (0.875 milligram per kilogram per course \[mg/kg/course\] for two courses plus placebo for two courses); b) cladribine at a high dose (0.875 mg/kg/course for four courses); or c) placebo (four courses). During the re-treatment period (Weeks 49 to 96), subjects received either a) cladribine at a low dose (0.875 mg/kg/course for two courses); or b) placebo (two courses). For all randomized subjects, there is a rescue option of treatment with Rebif® (interferon beta-1a 44 microgram (mcg) given subcutaneously three times a week), if the subject experienced more than one qualifying relapse, and/or experienced a sustained increase in their EDSS score of greater than or equal to (\>=) 1 point, or \>=1.5 points if baseline EDSS score is 0, (over a period of three months or greater), during a calendar year beginning at Week 24. To maintain the blind, there is a treating physician who view clinical laboratory results and assess adverse events and safety information, and an independent blinded evaluating physician who will perform neurological exams. A central neuroradiology center, also blinded to treatment, will assess magnetic resonance imaging (MRI) evaluations.

Interventions

DRUGCladribine 5.25 mg/kg

Cladribine tablet will be administered as cumulative dose of 0.875 milligram per kilogram (mg/kg) over a course of 4 or 5 consecutive days of 28-day period at Week 1, 5, 9, 13, 48, and 52 resulting in total cladribine dose of 5.25 mg/kg during the treatment period of 96 weeks.

DRUGCladribine 3.5 mg/kg

Cladribine tablet will be administered as cumulative dose of 0.875 mg/kg over a course of 4 or 5 consecutive days of 28-day period at Weeks 1, 5, 48, and 52 and placebo matched to cladribine tablet will be administered at Week 9 and 13 resulting in total cladribine dose of 3.5 mg/kg during the treatment period of 96 weeks.

OTHERPlacebo

Placebo matched to cladribine tablet will be administered over a course of 4 or 5 consecutive days of 28-day period at Weeks 1, 5, 9, 13, 48 and 52 during the treatment period of 96 weeks.

Sponsors

EMD Serono
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Investigator)

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No

Inclusion criteria

* Male or female, between 18 and 65 years of age (inclusive, at time of informed consent) * Has definite MS according to the McDonald criteria * Has relapsing-remitting disease with 1 or more relapses within 12 months prior to Study Day 1 * Must have been clinically stable and not has a relapse within 28 days prior to Study Day 1 * Has MRI consistent with MS at the pre-study evaluation according to the Fazekas criteria * Has a EDSS score from 0 to 5.5, inclusive * Weighed between 40-120 kilogram (kg), inclusive * If female, she must: 1. be post-menopausal or surgically sterilized; or 2. uses a hormonal contraceptive, intra uterine device, diaphragm with spermicide, or condom with spermicide, for the duration of the study; and 3. be neither pregnant nor breast-feeding * If male, he must be willing to use contraception to avoid pregnancies * Be willing and able to comply with study procedures for the duration of the study * Voluntarily provides written informed consent, and for United states of America (USA) sites only, a subject authorization under Health Insurance Portability and Accountability Act (HIPAA)

Exclusion criteria

* Has secondary progressive MS (SPMS) or primary progressive MS (PPMS) * Prior use of disease modifying drugs (DMDs) within the last 3 months, or 2 or more prior treatment failures with DMDs on the basis of efficacy * Has significant leukopenia (white blood cell count less than 0.5 times the lower limit of normal of the central laboratory) within 28 days prior to Study Day 1 * Has received cladribine, mitoxantrone, total lymphoid irradiation, myelosuppressive therapy, campath-1h, cyclophosphamide, azathioprine, methotrexate or natalizumab * Has received oral or systemic corticosteroids or adrenocorticotropic hormone within 28 days prior to Study Day 1 * Has compromised immune function or infection * Has received oral or systemic corticosteroids or adrenocorticotropic hormone within 28 days prior to Study Day 1 * Has received cytokine-based therapy, intravenous immunoglobulin therapy, or plasmapheresis within 3 months prior to Study Day 1 * Has platelet and absolute neutrophil counts below the lower limit of normal range within 28 days prior to Study Day 1 * Has prior or current history of malignancy * Has a history of persistent anemia, leukopenia, neutropenia, or thrombocytopenia after immunosuppressive therapy * Has systemic disease that, in the opinion of the Investigator, might interfere with subject safety, compliance or evaluation of the condition under Study (for example, insulin-dependent diabetes, Lyme disease, clinically significant cardiac, hepatic, or renal disease, Human Immunodeficiency Virus, or Human T-Cell Lymphotrophic Virus Type-1) * Has a psychiatric disorder that, in the opinion of the Investigator, was unstable or would preclude safe participation in the study * Has allergy or hypersensitivity to gadolinium, to cladribine or any of its excipients * Has used any investigational drug or experimental procedure within 6 months prior to Study Day 1

Design outcomes

Primary

MeasureTime frameDescription
Annualized Qualifying Relapse RateWeek 96A qualifying relapse was defined as an increase of 2 points in at least one functional system of the expanded disability status scale (EDSS) or an increase of 1 point in at least two functional systems (excluding changes in bowel or bladder function or cognition) in the absence of fever, lasting for at least 24 hours and to have been preceded by at least 30 days of clinical stability or improvement. Expanded disability status scale (EDSS) assesses disability in 8 functional systems. An overall score ranging from 0 (normal) to 10 (death due to multiple sclerosis \[MS\]) was calculated. The annualized relapse rate for each treatment group was calculated as the total number of confirmed relapses divided by the total number of days on study multiplied by 365.25.

Secondary

MeasureTime frameDescription
Percentage of Relapse-free ParticipantsWeek 96A qualifying relapse was defined as an increase of 2 points in at least one functional system of the EDSS or an increase of 1 point in at least two functional systems (excluding changes in bowel or bladder function or cognition) in the absence of fever, lasting for at least 24 hours and to have been preceded by at least 30 days of clinical stability or improvement. Expanded disability status scale (EDSS) assesses disability in 8 functional systems. An overall score ranging from 0 (normal) to 10 (death due to MS) was calculated.
Time to Disability ProgressionBaseline up to Week 96Time to disability progression was defined as the time to a sustained increase in EDSS score of at least 1 point if baseline EDSS score between 0.5 and 4.5 inclusively, or at least 1.5 points if the baseline EDSS score was 0, or at least 0.5 point if the baseline EDSS score was at least 5, over a period of at least three months. Expanded disability status scale (EDSS) assesses disability in 8 functional systems. An overall score ranging from 0 (normal) to 10 (death due to MS) was calculated. Tenth Percentile of time to sustained increase in EDSS score was reported using Kaplan-Meier survival curve.
Mean Number of Combined Unique (CU) Lesions, Active Time Constant 2 (T2) Lesions, and Active Time Constant 1 (T1) Gadolinium-Enhanced (Gd+) Lesions Per Participant Per ScanWeek 96Mean Number of CU lesions, active T2 lesions, and active T1 Gd+ lesions were measured by using magnetic resonance imaging (MRI) scans.

Participant flow

Participants by arm

ArmCount
Cladribine 5.25 mg/kg
Cladribine tablet administered as cumulative dose of 0.875 milligram per kilogram (mg/kg) over a course of 4 or 5 consecutive days of 28-day period at Week 1, 5, 9, 13, 48, and 52 resulting in total cladribine dose of 5.25 mg/kg during the treatment period of 96 weeks.
456
Cladribine 3.5 mg/kg
Cladribine tablet administered as cumulative dose of 0.875 mg/kg over a course of 4 or 5 consecutive days of 28-day period at Week 1, 5, 48, and 52 and placebo matched to cladribine tablet was administered at Week 9 and 13 resulting in total cladribine dose of 3.5 mg/kg during the treatment period of 96 weeks.
433
Placebo
Placebo matched to cladribine tablet administered over a course of 4 or 5 consecutive days of 28-day period at Week 1, 5, 9, 13, 48 and 52 during the treatment period of 96 weeks.
437
Total1,326

Withdrawals & dropouts

PeriodReasonFG000FG001FG002
Overall StudyAdverse Event955
Overall StudyDeath112
Overall StudyDisease progression4521
Overall StudyLost to Follow-up1184
Overall StudyOther211215
Overall StudyProtocol Violation4410

Baseline characteristics

CharacteristicCladribine 5.25 mg/kgCladribine 3.5 mg/kgPlaceboTotal
Age, Continuous39.1 years
STANDARD_DEVIATION 9.9
37.9 years
STANDARD_DEVIATION 10.3
38.7 years
STANDARD_DEVIATION 9.9
38.6 years
STANDARD_DEVIATION 10
Sex: Female, Male
Female
312 Participants298 Participants288 Participants898 Participants
Sex: Female, Male
Male
144 Participants135 Participants149 Participants428 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
deaths
Total, all-cause mortality
— / —— / —— / —
other
Total, other adverse events
324 / 454286 / 430242 / 435
serious
Total, serious adverse events
41 / 45436 / 43028 / 435

Outcome results

Primary

Annualized Qualifying Relapse Rate

A qualifying relapse was defined as an increase of 2 points in at least one functional system of the expanded disability status scale (EDSS) or an increase of 1 point in at least two functional systems (excluding changes in bowel or bladder function or cognition) in the absence of fever, lasting for at least 24 hours and to have been preceded by at least 30 days of clinical stability or improvement. Expanded disability status scale (EDSS) assesses disability in 8 functional systems. An overall score ranging from 0 (normal) to 10 (death due to multiple sclerosis \[MS\]) was calculated. The annualized relapse rate for each treatment group was calculated as the total number of confirmed relapses divided by the total number of days on study multiplied by 365.25.

Time frame: Week 96

Population: The intention-to-treat (ITT) population included all participants who were randomized in the study.

ArmMeasureValue (NUMBER)Dispersion
Cladribine 5.25 mg/kgAnnualized Qualifying Relapse Rate0.15 relapses per year95% Confidence Interval 0.58
Cladribine 3.5 mg/kgAnnualized Qualifying Relapse Rate0.14 relapses per year95% Confidence Interval 0.59
PlaceboAnnualized Qualifying Relapse Rate0.33 relapses per year95% Confidence Interval 0.88
p-value: <0.00195% CI: [0.35, 0.54]Wald Chi-square test
p-value: <0.00195% CI: [0.34, 0.54]Wald Chi-square test
Secondary

Mean Number of Combined Unique (CU) Lesions, Active Time Constant 2 (T2) Lesions, and Active Time Constant 1 (T1) Gadolinium-Enhanced (Gd+) Lesions Per Participant Per Scan

Mean Number of CU lesions, active T2 lesions, and active T1 Gd+ lesions were measured by using magnetic resonance imaging (MRI) scans.

Time frame: Week 96

Population: The ITT population included all participants who were randomized in the study.

ArmMeasureGroupValue (LEAST_SQUARES_MEAN)Dispersion
Cladribine 5.25 mg/kgMean Number of Combined Unique (CU) Lesions, Active Time Constant 2 (T2) Lesions, and Active Time Constant 1 (T1) Gadolinium-Enhanced (Gd+) Lesions Per Participant Per ScanActive T1 Gd+ lesions0.11 lesionsStandard Error 0.05
Cladribine 5.25 mg/kgMean Number of Combined Unique (CU) Lesions, Active Time Constant 2 (T2) Lesions, and Active Time Constant 1 (T1) Gadolinium-Enhanced (Gd+) Lesions Per Participant Per ScanCU lesions0.38 lesionsStandard Error 0.08
Cladribine 5.25 mg/kgMean Number of Combined Unique (CU) Lesions, Active Time Constant 2 (T2) Lesions, and Active Time Constant 1 (T1) Gadolinium-Enhanced (Gd+) Lesions Per Participant Per ScanActive T2 lesions0.33 lesionsStandard Error 0.06
Cladribine 3.5 mg/kgMean Number of Combined Unique (CU) Lesions, Active Time Constant 2 (T2) Lesions, and Active Time Constant 1 (T1) Gadolinium-Enhanced (Gd+) Lesions Per Participant Per ScanActive T1 Gd+ lesions0.12 lesionsStandard Error 0.05
Cladribine 3.5 mg/kgMean Number of Combined Unique (CU) Lesions, Active Time Constant 2 (T2) Lesions, and Active Time Constant 1 (T1) Gadolinium-Enhanced (Gd+) Lesions Per Participant Per ScanCU lesions0.43 lesionsStandard Error 0.08
Cladribine 3.5 mg/kgMean Number of Combined Unique (CU) Lesions, Active Time Constant 2 (T2) Lesions, and Active Time Constant 1 (T1) Gadolinium-Enhanced (Gd+) Lesions Per Participant Per ScanActive T2 lesions0.38 lesionsStandard Error 0.07
PlaceboMean Number of Combined Unique (CU) Lesions, Active Time Constant 2 (T2) Lesions, and Active Time Constant 1 (T1) Gadolinium-Enhanced (Gd+) Lesions Per Participant Per ScanCU lesions1.72 lesionsStandard Error 0.08
PlaceboMean Number of Combined Unique (CU) Lesions, Active Time Constant 2 (T2) Lesions, and Active Time Constant 1 (T1) Gadolinium-Enhanced (Gd+) Lesions Per Participant Per ScanActive T2 lesions1.43 lesionsStandard Error 0.06
PlaceboMean Number of Combined Unique (CU) Lesions, Active Time Constant 2 (T2) Lesions, and Active Time Constant 1 (T1) Gadolinium-Enhanced (Gd+) Lesions Per Participant Per ScanActive T1 Gd+ lesions0.91 lesionsStandard Error 0.05
Secondary

Percentage of Relapse-free Participants

A qualifying relapse was defined as an increase of 2 points in at least one functional system of the EDSS or an increase of 1 point in at least two functional systems (excluding changes in bowel or bladder function or cognition) in the absence of fever, lasting for at least 24 hours and to have been preceded by at least 30 days of clinical stability or improvement. Expanded disability status scale (EDSS) assesses disability in 8 functional systems. An overall score ranging from 0 (normal) to 10 (death due to MS) was calculated.

Time frame: Week 96

Population: The ITT population included all participants who were randomized in the study.

ArmMeasureValue (NUMBER)
Cladribine 5.25 mg/kgPercentage of Relapse-free Participants78.9 percentage of participants
Cladribine 3.5 mg/kgPercentage of Relapse-free Participants79.7 percentage of participants
PlaceboPercentage of Relapse-free Participants60.9 percentage of participants
Secondary

Time to Disability Progression

Time to disability progression was defined as the time to a sustained increase in EDSS score of at least 1 point if baseline EDSS score between 0.5 and 4.5 inclusively, or at least 1.5 points if the baseline EDSS score was 0, or at least 0.5 point if the baseline EDSS score was at least 5, over a period of at least three months. Expanded disability status scale (EDSS) assesses disability in 8 functional systems. An overall score ranging from 0 (normal) to 10 (death due to MS) was calculated. Tenth Percentile of time to sustained increase in EDSS score was reported using Kaplan-Meier survival curve.

Time frame: Baseline up to Week 96

Population: The ITT population included all participants who were randomized in the study.

ArmMeasureValue (NUMBER)
Cladribine 5.25 mg/kgTime to Disability Progression13.6 months
Cladribine 3.5 mg/kgTime to Disability Progression13.6 months
PlaceboTime to Disability Progression10.8 months

Source: ClinicalTrials.gov · Data processed: Apr 1, 2026