Conditions: Multiple Sclerosis
Keywords: Clinically Isolated Syndrome (CIS) Early MS Multiple Sclerosis
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 617
Healthy volunteers: no

Brief summary:
A randomized, double-blind, clinical trial to assess the safety and efficacy of two doses of oral cladribine versus placebo in participants who had a first clinical demyelinating event (clinically isolated syndrome). Participants in either the cladribine or placebo group may also enter treatment periods with open-label interferon-beta or open-label cladribine depending upon the disease status. The primary objective of this study is to evaluate the effect of two dosage regimens of oral cladribine versus placebo on the time to conversion to multiple sclerosis (MS) (from randomization) according to the Poser criteria in participants with first clinical demyelinating event at high risk of converting to MS.

Detailed description:
This will be a randomized, double blind, three-arm, placebo-controlled, multi-center trial to evaluate the safety and efficacy of oral cladribine versus placebo in the treatment of participants who have sustained a first clinical demyelinating event within 75 days prior to the Screening. Participants must have a minimum of 2 clinically silent lesions on the Screening magnetic resonance imaging (MRI).

The study will include a pre-study evaluation period (Screening period: between 10 and 28 days prior to the start of treatment with blinded study medication (oral cladribine or placebo).

Depending upon the clinical course of their MS, participants will then proceed from the ITP to either the Maintenance Treatment Period (with open-label interferon-beta treatment) or LTFU period (with either open-label low-dose cladribine or no additional treatment (if no progression to MS has been noted after the initial treatment period). The single primary endpoint for the overall study, which will be determined during the ITP, is time to conversion to MS (from randomization), according to the Poser criteria.

For every participants, eligibility for study enrollment and entry into each of the study periods, and diagnosis of conversion to either McDonald MS or CDMS must be confirmed and approved by a Sponsor appointed study Adjudication Committee.

Arms:
arm 1: Cladribine tablets administered as cumulative dose of 0.875 mg/kg over a course of 5 consecutive days at Weeks 1, 5, 9, 13, 48, and 52 resulting in total cladribine dose of 5.25 milligrams per kilograms (mg/kg) during the ITP of 96 weeks or until clinically definite multiple sclerosis (CDMS) conversion, whichever occurred first. arm 2: Cladribine tablets administered as cumulative dose of 0.875 mg/kg over a course of 5 consecutive days at Weeks 1, 5, 48, 52 and placebo matched to cladribine tablets was administered at Week 9 and 13 resulting in total cladribine dose of 3.5 mg/kg during the ITP of 96 weeks or until CDMS conversion, whichever occurred first. arm 3: Placebo matched to cladribine tablets administered over a course of 5 consecutive days at Weeks 1, 5, 9, 13, 48 and 52 during the ITP of 96 weeks or until CDMS conversion, whichever occurred first. arm 4: Participants who received cladribine 5.25 mg/kg and converted to CDMS during ITP entered in open-label maintenance period (OLMP) and received Rebif® new formulation (RNF) subcutaneously at a dose of 44 microgram (mcg) three times a week for up to 96 weeks. Due to trial termination, the OLMP duration was reduced for some participants. arm 5: Participants who received cladribine 3.5 mg/kg and converted to CDMS during ITP entered in OLMP and received RNF subcutaneously at a dose of 44 mcg three times a week for up to 96 weeks. Due to trial termination, the OLMP duration was reduced for some participants. arm 6: Participants who received placebo and converted to CDMS during ITP entered in OLMP and received RNF subcutaneously at a dose of 44 mcg three times a week for up to 96 weeks. Due to trial termination, the OLMP duration was reduced for some participants. arm 7: Participants who received cladribine 5.25 mg/kg and did not convert to CDMS during ITP, entered in long-term follow-up (LTFU) period. Participants who converted to McDonald multiple sclerosis (MS) during ITP or during LTFU period received open-label cladribine tablets (3.5 mg/kg) during LTFU period. Participants who converted to CDMS during LTFU received RNF subcutaneously at a dose of 44 mcg three times a week for the remaining LTFU period. Under the original study design, total duration of LTFU period was up to 96 weeks. The LTFU duration was reduced due to trial termination. Following the notice of trial termination, no further open label cladribine treatment was administered during the LTFU. arm 8: Participants who received cladribine 3.5 mg/kg and did not convert to CDMS during ITP, entered in long-term follow-up (LTFU) period. Participants who converted to McDonald multiple sclerosis (MS) during ITP or during LTFU period received open-label cladribine tablets (3.5 mg/kg) during LTFU period. Participants who converted to CDMS during LTFU received RNF subcutaneously at a dose of 44 mcg three times a week for the remaining LTFU period. Under the original study design, total duration of LTFU period was up to 96 weeks. The LTFU duration was reduced due to trial termination. Following the notice of trial termination, no further open label cladribine treatment was administered during the LTFU. arm 9: Participants who received placebo and did not convert to CDMS during ITP, entered in long-term follow-up (LTFU) period. Participants who converted to McDonald multiple sclerosis (MS) during ITP or during LTFU period received open-label cladribine tablets (3.5 mg/kg) during LTFU period. Participants who converted to CDMS during LTFU received RNF subcutaneously at a dose of 44 mcg three times a week for the remaining LTFU period. Under the original study design, total duration of LTFU period was up to 96 weeks. The LTFU duration was reduced due to trial termination. Following the notice of trial termination, no further open label cladribine treatment was administered during the LTFU. arm 10: Participants who received cladribine 5.25 mg/kg and did not convert to CDMS during ITP, entered in LTFU period. Participants who did not convert to McDonald MS during ITP did not receive any treatment during LTFU period. Participants who converted to CDMS during LTFU period received RNF subcutaneously at a dose of 44 mcg three times a week for the remaining LTFU period. Under the original study design, total duration of LTFU period was up to 96 weeks. The LTFU duration was reduced due to trial termination. Following the notice of trial termination, no further open label cladribine treatment was administered during the LTFU. arm 11: Participants who received cladribine 3.5 mg/kg and did not convert to CDMS during ITP, entered in LTFU period. Participants who did not convert to McDonald MS during ITP did not receive any treatment during LTFU period. Participants who converted to CDMS during LTFU period received RNF subcutaneously at a dose of 44 mcg three times a week for the remaining LTFU period. Under the original study design, total duration of LTFU period was up to 96 weeks. The LTFU duration was reduced due to trial termination. Following the notice of trial termination, no further open label cladribine treatment was administered during the LTFU. arm 12: Participants who received placebo and did not convert to CDMS during ITP, entered in LTFU period. Participants who did not convert to McDonald MS during ITP did not receive any treatment during LTFU period. Participants who convert to CDMS during LTFU period received RNF subcutaneously at a dose of 44 mcg three times a week for the remaining LTFU period. Under the original study design, total duration of LTFU period was up to 96 weeks. The LTFU duration was reduced due to trial termination. Following the notice of trial termination, no further open label cladribine treatment was administered during the LTFU.

Interventions: intervention 1: Cladribine intervention 2: Placebo intervention 3: Rebif® new formulation (RNF)
Intervention descriptions: intervention 1: Cladribine tablets were administered until CDMS conversion, whichever occur first. intervention 2: Placebo matched to cladribine tablets were administered. intervention 3: Participants who converted to CDMS during ITP entered in open-label maintenance period (OLMP) and received RNF subcutaneously at a dose of 44 microgram (mcg) three times a week. Participants who converted to CDMS during long-term follow-up (LTFU) period, received RNF subcutaneously at a dose of 44 mcg three times a week.

Protocol document: