A phase I dose-escalating clinical trial will be conducted in a coordinated and comprehensive manner to determine safety and tolerability, and to enable selection of a suitable dose regimen for phase II trials. The primary objective of the phase I study will be to determine whether tolDC-based therapy is safe and well tolerated and to establish the dose-response, with clinical relapse rates, neurological disability (assessed using various scales) and MRI endpoints, measured over 12 months. Patients will serve as their own controls pre- and post-vaccination. Completion of screening assessments and confirmation of eligibility criteria should take no longer than 6 weeks. First-line treatments will be stopped 6 weeks before baseline at the latest.