A Phase IIIB, Double Blind, Placebo-Controlled, Multcenter, 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)

INTERVENTION: CONDITION: ; Multiple sclerosis 10012303 PRIMARY OUTCOME: Primary parameter: to evaluate the safety and the tolerability of oral ; cladribine and to evaluate the effect on the QTc interval. ; Safety enpoints: ; proportion of subjects with grades 3 or 4 adverse events ; proportion of subjects with at least one grade 4 CTC adverse event toxicity ; mean change in lab values ; incidence of adverse events and serious adverse events ; mean change in QTc interval from baseline ; ; Other endpoints: ; proportion of subjects relapse free ; disability progression assessed at annuals intervals ; time to confirmed EDSS progression ; MRI endpoints ; pharmacoeconomic and health outcomes ; ; For more details : see protocol synopsis page 12 , 13 and 14.; SECONDARY OUTCOME: Secundary paramaters: ; ‐explore the long term benefit (rate of disease progression as reflected by ; rate of change in Expanded Disabiltiy Status Score) of treatment with oral ; cladribine vs. placebo. ; ‐explore the relationship between oral cladribine treatments and immunologic ; parameters, MRI measurments of disease activities, clinical relapses and ; disease progression in subjects previously randomised in trial 25643. ; ‐determinate the benefit of continued oral cladribine treatment on ; health‐related quality of life and economic outcome measures. ; INCLUSION CRITERIA: the patient must have completed his randomized treatment in study 25643 ( CLarity)