Comparison of the effects of different CDP323 doses given over a period of four weeks on blood biomarkers in subjects with relapsing forms of multiple sclerosis.

Inclusion Criteria:

• Female and male subjects aged 18-65 years
• Relapsing form of MS with at least one clinical relapse in the 24 months before screening;
• Screening EDSS score of 0-6.5;
• Must be fully immunocompetent
• Female subjects of childbearing potential must agree to practice contraception methods

Exclusion Criteria:

• Any conditions that could interfere with the contrast-enhanced MRI;
• Any clinically significant disease state or findings other than MS;
• Any clinically significant deviation from the pre-defined ranges for laboratory tests;
• Concomitant treatment with MS disease modifying drugs