Efficacy and Safety of Vatelizumab in Patients Who Completed Treatment in Study DRI13839

Inclusion criteria: Patients who completed the 12-week treatment period in DRI13839. Exclusion criteria: * Any clinically significant or ongoing adverse events, or laboratory abnormalities from DRI13839 that per Investigator judgment would adversely affect the patient's participation in the long-term extension study. * Confirmed platelet count below the lower limit of normal at any time during DRI13839. * Pregnancy or breast-feeding. * Other protocol defined exclusion criteria may apply. The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.