Efficacy and Safety of CDP6038 in Patients With Rheumatoid Arthritis With an Unsuccessful Response to Anti-Tumor Necrosis Factor (Anti-TNF) Therapy

CDP6038 is a protein (antibody) that blocks interleukin-6 (IL-6), a substance involved in
the inflammation associated with rheumatoid arthritis. This is a multicenter, 12-week,
randomized, double-blind, placebo- and active- controlled study comparing several doses and
dosage regimens (every 2 weeks and every 4 weeks) of CDP6038 to placebo and tocilizumab in
patients with active rheumatoid arthritis who have had an unsuccessful response to
methotrexate and previous anti-TNF therapy. The study will test if CDP6038 is more
efficacious than placebo in reducing the signs and symptoms of rheumatoid arthritis at 12
weeks while maintaining an adequate safety profile. In order to maintain the study blinding
all subjects will be given a subcutaneous (sc) injection (under the skin) every 2 weeks, as
well as an intravenous (iv) infusion every 4 weeks. In addition subjects must remain on
stable weekly doses of methotrexate. Assessments during the study include evaluations of
joint pain and swelling, laboratory blood and urine tests, physical examinations, vital
signs, electrocardiograms, and questionnaires. Subjects who complete the 12-week study will
be eligible to enroll in a long-term extension study receiving CDP6038.