The humanised IgG4 monoclonal antibody GNbAC1 targets the envelope protein (Env) of the human endogenous multiple sclerosis-associated retrovirus (HERV-W MSRV), which may play a critical role in multiple sclerosis (MS).

This study evaluates the effect on MRI lesions parameters, the safety and pharmacokinetics of GNbAC1 in patients with relapsing remitting multiple sclerosis.

Main Inclusion Criteria:

• For male or female with reproductive potential, use of reliable means of contraception;
• RRMS according to the 2010 revised McDonald criteria;
• Disease activity characterised by at least one documented relapse within the last 12 months and /or at least one Gd-enhancing T1 lesion at selection or evidenced within the last 3 months;
• EDSS score < 6.0.

Main Exclusion Criteria:

• Patients suffering from Secondary Progressive MS and Primary Progressive MS at screening;
• Pregnant and nursing women.